Endangered and Threatened Wildlife and Plants; Revised Endangered Status, Revised Critical Habitat Designation, and Taxonomic Revision for Monardella linoides ssp. viminea

Federal RegisterJun 9, 2011

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R8-ES-2010-0076]

RIN 1018-AX18

Endangered and Threatened Wildlife and Plants; Revised Endangered Status, Revised Critical Habitat Designation, and Taxonomic Revision for

Monardella linoides

ssp.

viminea

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Proposed rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), propose to recognize the recent change to the taxonomy of the currently endangered plant taxon,

Monardella linoides

ssp.

viminea,

in which the subspecies was split into two distinct full species,

Monardella viminea

(willowy monardella) and

Monardella stoneana

(Jennifer's monardella). Because the original subspecies,

Monardella linoides

ssp.

viminea,

was listed as endangered under the Endangered Species Act of 1973, as amended (Act), we are reviewing and updating the threats analysis that we completed for the taxon in 1998, when it was listed as a subspecies, to determine if any of that analysis has changed based on this revised taxonomy. We are also reviewing the status of the new species,

Monardella stoneana.

We propose that

Monardella viminea'

s current listing status should be retained as endangered, and we propose to delist the portion of the old listed taxon that has been split off into the new species,

Monardella stoneana,

because it does not meet the definition of endangered or threatened under the Act. We also propose to designate critical habitat for

Monardella viminea

(willowy monardella). Approximately 348 acres (141 hectares) are proposed for designation as critical habitat for

M. viminea,

in San Diego County, California. We are not proposing to designate critical habitat for

Monardella stoneana

at this time because we do not believe this species warrants listing under the Act. However, should we determine, after review of the best available scientific information and public comment, that

Monardella stoneana

does warrant listing, we will propose critical habitat for

Monardella stoneana,

should it be determined to be prudent, in a separate proposed rule.

DATES:

We will accept comments received or postmarked on or before August 8, 2011. We must receive requests for public hearings, in writing, at the address shown in the

ADDRESSES

section by July 25, 2011.

ADDRESSES:

You may submit comments by one of the following methods:

(1)

Electronically

: Go to the Federal eRulemaking Portal:

http://www.regulations.gov

. In the Keyword box, enter Docket No. FWS-R8-ES-2010-0076, which is the docket number for this rulemaking. Then, in the Search panel on the left side of the screen, under the Document Type heading, click on the Proposed Rules link to locate this document. You may submit a comment by clicking on “Send a Comment or Submission.”

(2)

By hard copy

: Submit by U.S. mail or hand-delivery to: Public Comments Processing, Attn: FWS-R8-ES-2010-0076; Division of Policy and Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive, MS 2042-PDM; Arlington, VA 22203.

We will not accept e-mail or faxes. We will post all comments on

http://www.regulations.gov.

This generally means that we will post any personal information you provide us (see the Public Comments section below for more information).

FOR FURTHER INFORMATION CONTACT:

Jim Bartel, Field Supervisor, U.S. Fish and Wildlife Service, Carlsbad Fish and Wildlife Office, 6010 Hidden Valley Road, Suite 101, Carlsbad, CA 92011; telephone 760-431-9440; facsimile 760-431-5901. If you use a telecommunications device for the deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Public Comments

We intend any final action resulting from this proposed rule will be based on the best scientific and commercial data available and be as accurate and as effective as possible. Therefore, we request comments or information from other concerned government agencies, the scientific community, industry, or any other interested party concerning this proposed rule. Please note that throughout the remainder of this document we will use the currently recognized names,

Monardella viminea,

for references to willowy monardella, and

Monardella stoneana,

for references to Jennifer's monardella. We particularly seek comments concerning:

(1) Specific information regarding our recognition of

Monardella viminea

and

M. stoneana

at the species rank, on the segregation of ranges of

M. stoneana

and

M. viminea,

and on our proposals that

M. viminea

should remain listed as endangered and that

M. stoneana

does not warrant listing under the Act (16 U.S.C. 1531

et seq.

(2) Any available information on known or suspected threats and proposed or ongoing development projects with the potential to threaten either

Monardella viminea

M. stoneana

(3) The effects of potential threat factors to both

Monardella viminea

and

M. stoneana

that are the basis for a listing determination under section 4(a) of the Act, which are:

(a) The present or threatened destruction, modification, or curtailment of the species' habitat or range;

(b) Overutilization for commercial, recreational, scientific, or educational purposes;

(d) The inadequacy of existing regulatory mechanisms; or

(e) Other natural or manmade factors affecting its continued existence.

(4) Specific information regarding impacts of fire on

Monardella viminea

M. stoneana

individuals or their habitat.

(5) The reasons why we should or should not designate habitat as “critical habitat” under section 4 of the Act for

Monardella viminea

including whether there are threats to the species from human activity, the degree of which can be expected to increase due to the designation, and whether that increase in threats outweighs the benefit of designation such that the designation of critical habitat may not be prudent.

(6) Specific information on:

(a) The amount and distribution of

Monardella viminea

M. stoneana

habitat,

(b) What areas, that were occupied at the time of listing (or are currently occupied) and that contain features essential to the conservation of these species, should be included in the designation and why,

(c) Special management considerations or protection that may be needed in critical habitat areas we are proposing, including managing for the potential effects of climate change, and

(d) What areas not occupied at the time of listing are essential for the conservation of the species and why.

(7) Information that may assist us in identifying or clarifying the physical and biological features essential to the conservation of

Monardella viminea.

(8) How the proposed critical habitat boundaries could be refined to more closely or accurately circumscribe the areas identified as containing the

physical and biological features essential to the conservation of

Monardella viminea.

(9) How we could improve or modify our design of critical habitat units, particularly our criteria for width of essential habitat for

Monardella viminea.

We especially request information on West Sycamore Canyon and Unit 2 (where two groups of

M. viminea

were not included under the criteria used to draw proposed critical habitat boundaries) and areas such as Elanus, Lopez, and Rose Canyons that we have identified as not meeting the definition of critical habitat.

(10) Information on pollinators of

Monardella viminea

M. stoneana

that may be essential for the conservation of these species, including information on areas that provide habitat for these pollinators.

(11) Land use designations and current or planned activities in the subject areas and their possible impacts on proposed critical habitat.

(12) Information on the projected and reasonably likely impacts of climate change on the two species and the proposed critical habitat.

(13) Information on any quantifiable economic costs or benefits of the proposed designation of critical habitat.

(14) Any probable economic, national security, or other relevant impacts of designating any area that may be included in the final designation; in particular, any impacts on small entities or families, and the benefits of including or excluding areas that exhibit these impacts.

(15) Whether any specific areas we are proposing for critical habitat designation for

Monardella viminea

should be considered for exclusion under section 4(b)(2) of the Act, and whether the benefits of potentially excluding any specific area outweigh the benefits of including that area under section 4(b)(2) of the Act, in particular for those lands covered by the County of San Diego Subarea Plan or the City of San Diego Subarea Plan under the Multiple Species Conservation Program (MSCP). Information on obtaining copies of these plans will be provided by the U.S. Fish and Wildlife Service, Carlsbad Fish and Wildlife Office (see

FOR FURTHER INFORMATION CONTACT

(16) Whether we could improve or modify our approach to designating critical habitat in any way to provide for greater public participation and understanding, or to better accommodate public concerns and comments.

You may submit your comments and materials concerning this proposed revised rule by one of the methods listed in the

ADDRESSES

section. We will not accept comments sent by e-mail or fax or to an address not listed in the

ADDRESSES

section. We will post your entire comment—including your personal identifying information—on

http://www.regulations.gov.

You may request at the top of your document that we withhold personal information such as your street address, phone number, or e-mail address from public review; however, we cannot guarantee that we will be able to do so.

Comments and materials we receive, as well as supporting documentation we used in preparing the proposed rule, will be available for public inspection on

http://www.regulations.gov

(under Docket Number FWS-R8-ES-2010-0076), or by appointment, during normal business hours, at the U.S. Fish and Wildlife Service, Carlsbad Fish and Wildlife Office (see

FOR FURTHER INFORMATION CONTACT

Public Hearing

The Act provides for one or more public hearings on this proposal, if requested. Requests must be received by the date listed in the

DATES

section. Such requests must be made in writing and be addressed to the Field Supervisor at the address provided in the

FOR FURTHER INFORMATION CONTACT

section. We will schedule public hearings on this proposal, if any are requested, and announce the dates, times, and places of those hearings, as well as how to obtain reasonable accommodations, in the

Federal Register

and local newspapers at least 15 days before the hearing.

Background

It is our intent to discuss only those topics directly relevant to our recognition of the taxonomic split of

Monardella linoides

ssp.

viminea

into two distinct taxa:

Monardella viminea

(willowy monardella) and

Monardella stoneana

(Jennifer's monardella); the retention of

M. viminea

as endangered; the proposed critical habitat for

M. viminea;

and our conclusion that

M. stoneana

is not endangered or threatened. This proposed rule incorporates new information specific to

M. viminea

and

M. stoneana

including species descriptions, distributions, taxonomic rank, and nomenclature. We also provide information on current threats to the two species, potential pollinators, and additional information on soil not included in our listing rule for

Monardella linoides

ssp.

viminea

published in the

Federal Register

on October 13, 1998 (63 FR 54938), and our critical habitat designation published in the

Federal Register

on November 8, 2006 (71 FR 65662).

Previous Federal Action

Monardella linoides

ssp.

viminea

was listed as endangered in 1998 (63 FR 54938; October 13, 1998). An account of Federal actions prior to listing may be found in the listing rule (63 FR 54938; October 13, 1998). On November 9, 2005, we published a proposed rule to designate critical habitat for

M. linoides

ssp.

viminea

(70 FR 67956).

On November 8, 2006 (71 FR 65662), we published our final rule designating critical habitat for

M. linoides

ssp.

viminea.

On January 14, 2009, the Center for Biological Diversity filed a complaint in the U.S. District Court for the Southern District of California challenging our designation of critical habitat for

M. linoides

ssp.

viminea

(

Center for Biological Diversity

United States Fish and Wildlife Service and Dirk Kempthorne, Secretary of the Interior,

Case No. 3:09-CV-0050-MMA-AJB). A settlement agreement was reached with the plaintiffs dated November 14, 2009, in which we agreed to submit a proposed revised critical habitat designation to the

Federal Register

for publication by February 18, 2011, and a final revised critical habitat designation to the

Federal Register

for publication by February 17, 2012. By order dated February 10, 2011, the district court approved a modification to the settlement agreement that extended the deadline for

Federal Register

submission to June 18, 2011, for the proposed revised critical habitat designation. The deadline for submission of a final revised critical habitat designation to the

Federal Register

remains February 17, 2012.

Taxonomic and Nomenclatural Changes Affecting Monardella linoides ssp. viminea

In 2001, Kelly and Burrascano (2001, p. 4) noted that “multiple biologists” had observed differences in the southernmost occurrences of

Monardella linoides

ssp.

viminea.

Kelly and Burrascano (2001, p. 4) also stated that Andrew Sanders of the University of California at Riverside believed the plants were a separate species. Elvin and Sanders (2003, pp. 425-432) subsequently segregated the southern occurrences of willowy monardella as a distinct taxon and recognized it at the species rank as

M. stoneana

(see Figure 1)

Elvin and Sanders (2003, p. 430) also returned willowy monardella to its original specific rank as

M. viminea.

The Service initially disagreed with the segregation and classification of

M. stoneana

due to lack of sufficient

supportive evidence presented by Elvin and Sanders (Bartel and Wallace 2004, pp. 1-3), a view continued in our 5-year review (Service 2008, pp. 6-7).

Further genetic investigation of

Monardella

has recently been conducted using ISSR (Inter-Simple Sequence Repeats). ISSR is a general term for a genome region between microsatellite loci that can be used for DNA fingerprinting and delimiting species. ISSR analysis can have multiple application uses, including taxonomic studies of closely related species (Prince 2010, pers. comm.). Using ISSRs, Prince (2009, pp. 22-31) performed an extensive survey

Monardella

taxa and found that

M. stoneana

and

M. viminea

were both more closely related to different subspecies of

M. linoides

than to each other. These data are supportive of the earlier recognition by the California Department of Fish and Game (CDFG), California Natural Diversity Database (CNDDB), and the California Native Plant Society (CNPS) of

M. viminea

and

M. stoneana

as two separate taxa. Moreover,

M. viminea

and

M. stoneana

are treated as full species in the recently available online unpublished treatment of

Monardella

(Brunell

et al.,

in press) that will be published in the forthcoming revision of the Jepson Manual, the standard guide to the flora of California. According to the authors (Brunell

et al.,

in press), the two species can be morphologically differentiated based on slight differences in leaf width, bract length and width, and flower cluster width. Reportedly,

M. viminea

and

M. stoneana

will be similarly treated as separate species in the future treatment of the genus for the Flora of North America project (G. Wallace, Service 2010, pers. obs.). As a result of the new data and supportive references noted above, we propose to recognize the change in the taxonomic rank and nomenclature of the listed entity as two distinct species,

M. viminea

and

M. stoneana.

We have included those proposed changes in the Proposed Regulation Promulgation section of this rule, and we expect to adopt them when we publish a final determination for this action.

When we listed

Monardella linoides

ssp.

viminea,

we considered 20 occurrences to be extant in the United States (see Table 1) (63 FR 54938; October 13, 1998). As of 2008, 9 occurrences were considered to be extirpated, leaving 11 extant occurrences (Service 2008, p. 5). All 9 extirpated occurrences were in central San Diego County, in the range of what is now considered to be

M. viminea.

Based on updated information from Marine Corps Air Station (MCAS) Miramar (Kassebaum 2010, pers. comm.), two additional occurrences have since been extirpated, again in the range of

M. viminea.

Additionally, as a result of taxonomic changes, the two southernmost occurrences were reclassified as

M. stoneana

after the 2008 5-year review (see Table 1). Therefore, we believe there are now only seven occurrences of

M. viminea,

and these seven were extant at the time of listing. We are not aware of any new occurrences of

M. viminea,

other than those planted in 2007 as a conservation measure to offset impacts associated with the development of the Carroll Canyon Business Park. More information on the four translocated occurrences is discussed in the

Geographic Range and Status

section below. In addition to two occurrences now considered to be

M. stoneana

(but considered at listing to be

M. linoides

ssp.

viminea

we now know of an additional 7 occurrences of

M. stoneana,

all in what was once the southern range of

M. linoides

ssp.

viminea

(Figure 1). We presume those occurrences were extant at the time

M. linoides

ssp.

viminea

was listed. The single plant in the

M. stoneana

occurrence at Otay Lakes (

M. stoneana

EO 4, former

M. viminea

EO 28) was extirpated by the 2007 Harris fire. Therefore, we consider eight extant occurrences of

M. stoneana

Table 1—A Description of When Occurrences Were First Recognized by the Service, When They Were First Considered Extirpated, and Which Occurrences the Service Currently Considers Extant

Location

CNDDB element occurrence number (EO)

Known and extant at listing

Extant at 2008 5-yr review

Currently

extant

Monardella viminea:

Lopez Canyon

Cemetery Canyon

Carroll Canyon

Sycamore Canyon

San Clemente Canyon

12, 18, 19

San Clemente Canyon

Murphy Canyon

San Clemente Canyon

West Sycamore Canyon

Elanus Canyon

Carroll Canyon

Spring Canyon

San Clemente Canyon

Otay Lakes

Now considered

M. stoneana

EO4

Sycamore Canyon

Miramar NAS

Marron Valley

none

Now considered

M. stoneana

EO1

Monardella stoneana:

Marron Valley

N.W. Otay Mountain

Otay Lakes

Buschalaugh Cove

Cottonwood Creek

Copper Canyon

S. of Otay Mountain

Tecate Peak

Sources:

CNDDB 1998, 2007, 2010a, 2010b; Service 2008, Kassebaum 2010.

Throughout this document, we refer to previous reports and documents, including

Federal Register

publications. When evaluating information contained in documents issued prior to the present document, the reader must bear in mind that information may reference

Monardella viminea

M. linoides

ssp.

viminea

and may include statements or data referring to plants or populations now known as

M. stoneana.

Only information relevant to actions described in this proposed rule is provided below. For additional information on

Monardella viminea,

including a detailed description of its life history and habitat, refer to the final listing rule published in the

Federal Register

on October 13, 1998 (63 FR 54938), the final rule designating critical habitat published in the

Federal Register

on November 8, 2006 (71 FR 65662), and the 5-year review completed in March 2008 (Service 2008). Actions described below include status reviews of

M. viminea

and

M. stoneana,

and a proposed revision of the critical habitat designation for

M. viminea.

Status Review—

Monardella viminea

History of the Action

Federal actions taken prior to listing are described in the listing rule published in the

Federal Register

on October 13, 1998 (63 FR 54938). On November 9, 2005, we published a proposed rule to designate critical habitat for

Monardella linoides

ssp.

viminea

(70 FR 67956). On November 8, 2006 (71 FR 65662), we published our final rule designating critical habitat for

M. linoides

ssp.

viminea.

As described in the

Taxonomic and Nomenclatural Changes Affecting Monardella linoides

ssp.

viminea

section, genetic investigations conducted since the listing in 1998 and completed after our 2008 5-year review have provided the needed additional support for the recognition of

Monardella viminea

and

M. stoneana

as separate taxa at the species rank. This necessitates a review of the listing status of the remaining

M. viminea

occurrences and an assessment of the potential listing status of the newly segregated

M. stoneana.

Species Description

Monardella viminea

is a perennial herb or subshrub in the Lamiaceae (mint family) with a woody base and aromatic foliage. The waxy, green, hairy stems bear conspicuously gland-dotted linear or lance-shaped leaves, and dense, terminal clusters of white to rose-colored flowers. The leaves are 0.1-0.2 inch (in) (2-4 millimeters (mm)) wide at the base. The middle flower bracts are 0.4-0.6 in (10-15 mm) long (Elvin and Sanders 2003, p. 431).

Monardella viminea

grows in clumps of 1 to 4 individual plants (Ince and Krantz 2008, p. 2). As the number of plants within a clump cannot be reliably distinguished without exposing the roots,

M. viminea

is usually counted by clumps rather than as individual plants. Please see the Discussion of the Four Species section of the listing rule (63 FR 54938; October 13, 1998) and the Life History section of the 2005 proposed critical habitat rule (70 FR 67956; November 9, 2005) for more information on this species description.

Habitat

Monardella viminea

occurs in coastal sage scrub and riparian scrub in sandy bottoms and on banks of ephemeral washes in canyons where surface water flows for usually less than 48 hours after a rain event (Scheid 1985, p. 3; Elvin and Sanders 2003, p. 430; Kelly and Burrascano 2006, p. 51). These semi-open washes and drainage areas typically have little to no canopy cover (Reiser 1994, p. 139). The species is commonly found with

Eriogonum fasciculatum

(California buckwheat) and

Baccharis sarothroides

(broom baccharis) in habitats characterized by low herbaceous cover and some shrub cover (Scheid 1985, p. 38). It is most commonly found in canyon bottoms, north-facing slopes, and along bends of meandering drainages (Elvin and Sanders 2003, p. 426; Rebman and Dossey 2006a, p. 5). Many of these areas maintain water longer than other portions of the drainage, although they do not have long-term standing water (Elvin and Sanders 2003, p. 426). At Marine Corps Air Station (MCAS) Miramar,

M. viminea

is absent from steeper portions of the canyons and prevalent in secondary stream channels, which suggests

M. viminea

presence is correlated with reaches where flow is relatively slow-moving or standing water is present (Rebman and Dossey 2006a, pp. 5-8).

Monardella viminea

is found on soils characterized by a high content of coarse sandy grains and sediments and cobble deposits (Scheid 1985, p. 35). The larger sandy particles that make up

M. viminea

habitat soils are transported downstream by flood events (Scheid 1985, p. 36). Soil series that support

M. viminea

include Stony Land, Redding Gravelly Loam, Visalia Sandy Loam, and Riverwash (Scheid 1985, p. 35; Rebman and Dossey 2006a, pp. 5-6).

The 5-year review (Service 2008, p. 13) concluded that

Monardella viminea

requires a natural or managed regime of periodic, small fires. The coastal sage habitat that

M. viminea

favors benefits from small or managed fires that clear out dead or encroaching scrub vegetation and reduce nonnative species (Minnich 1983, p. 1290). However, there are two ways in which fire can negatively impact

M. viminea

habitat: (1) increased frequency of fires of all sizes, which can result in type conversion; or (2) invasion of nonnative grasses into riparian or coastal sage scrub habitats, which can choke out native vegetation, including shrubs associated with

M. viminea.

Additionally, large or unmanaged fires (sometimes referred to as “megafires”)

can be a particular threat to a narrow endemic species like

M. viminea

because a single megafire could eliminate a large proportion of individual plants within the extant range of the species, although

M. viminea

is capable of resprouting after fire (Rebman and Dossey 2006b, p. 2). Additional information is needed regarding the role of fire in

M. viminea

habitat, particularly within riparian portions of canyons. Please see our request for information in the Public Comments section above. For more information on and discussion of the species' description and its habitat see the Discussion of the Four Species section of the listing rule (63 FR 54938; October 13, 1998) and the Distribution and Status section of the proposed critical habitat rule (70 FR 67956; November 9, 2005). However, we ask the reader to keep in mind that plants now treated as

M. stoneana

and their habitat were included in the discussion at the time those documents were published.

Life History

Very little is known about the germination and establishment of

Monardella viminea.

Mature plants flower readily, with inflorescences (flower heads) persisting for 10 to 12 weeks (Elvin and Sanders 2003, pp. 430-431). Plants are short-lived perennials, producing a new cohort of aerial stems each year from a persisting perennial root structure. Plants of this species are not known to be rhizomatous (connected by creeping underground stems); however, root masses may become detached over time, resulting in adjacent genetically identical but spatially separate plants. Rebman and Dossey (2006a, p. 10) reported that the peak flowering period at MCAS Miramar is early June to mid-July, with occasional flowering from May through August and, more rarely, into September.

No pollination studies are known to exist for

Monardella viminea;

however, other

Monardella

taxa are visited by butterfly and bee species (Elvin 2004, p. 2). Bees collected from the closely related

M. linoides

include wasp-like bees (

Hylaeus

sp.), mason bees (

Osmia

spp. or

Chalicodoma

spp.), and miner bees (

Anthophora

spp.) (Hurd 1979, pp. 1762, 1765, 2042, 2073, and 2164). Several observers report European honeybees (

Apis mellifera

) and bumblebees (

Bombus

spp.) as frequent visitors to

M. viminea

flowers (Kelly and Burrascano 2001, p. 7; Kelly and Burrascano 2006, pp. 7-8; Rebman and Dossey 2006a, pp. 10-11). Wasps and bees from the Bembicine and Andrenid families were collected from

M. viminea

plants on MCAS Miramar (Kelly and Burrascano 2001, p. 8). Butterflies known to visit

M. viminea

flowers include painted ladies (

Vanessa cardui

) (Rebman and Dossey 2006a, p. 11), gray hairstreaks (

Strymon melinus

), and funereal duskywing skippers (

Erynnis funeralis

) (University of California, Berkeley, CalPhotos database 2009). Successful sexual reproduction of flowering plants often depends on pollinator abundance and effectiveness (Javorek

et al.

2002, p. 350). Therefore, adequate numbers of pollinators and sufficient pollinator movement through the habitat should be considered when assessing likely population distributions and survival, and habitat needs of

M. viminea.

Geographic Range and Status

Monardella viminea

is a geographically narrow endemic species restricted to three watersheds north of Kearny Mesa in San Diego County, California (Elvin and Sanders 2003, p. 431). The occurrences now considered to be

M. viminea

are entirely in the northern range of the originally listed entity

M. linoides

ssp.

viminea

(Figure 1). The portions of the watersheds where

M. viminea

occurs are found on lands owned by the Department of Defense at MCAS Miramar, and lands owned by the City of San Diego, lands owned by the County of San Diego, and lands under private ownership. In this proposed critical habitat we use the word “occurrence” when describing the location of plants (

e.g.,

in a critical habitat unit). In this context, we are referring to point locations or polygons representing observations of one or more

M. viminea

individuals. This may include one or more of the “element occurrences” (EOs) as described by CDFG in the CNDDB. Proposed critical habitat for

M. viminea

recognizes the importance of ecosystem processes that create and maintain suitable habitat for this species. Consequently, in the Critical Habitat sections of this document, our critical habitat units follow linear drainages that may include one or more of the “element occurrences” described by CNDDB. Because of the potentially transient nature of suitable habitat for this species, any reach along these drainages may be occupied at a given time. In all other respects in this document, “element occurrence” or “occurrence” references are those from the cumulative data of the CNDDB (2010a, EOs 1-31).

Figure 1. Range of

Monardella viminea

and

M. stoneana.

BILLING CODE 4310-55-P

EP09JN11.037

BILLING CODE 4310-55-C

As of 2008, all eleven known occurrences of

Monardella viminea

were considered declining in size (this total includes two occurrences known to be extirpated by 2010 and two occurrences now considered

M. stoneana

), as are four additional transplanted occurrences (see

Transplants

below) (Ince and Krantz 2008, p. 9; Service 2008 p. 5). On MCAS Miramar, the species has declined by 45 percent since the 2002 surveys, from 3,379 individual plants to 1,809 individual plants (Tierra Data 2011, p. 12). In the past 2 years, multiple clumps of

M. viminea

that burned in the 2003 Cedar Fire have resprouted (Kassebaum 2010, pers. comm.). The most recent survey of MCAS Miramar, conducted in 2009, found juveniles or seedlings present in all canyons except for Elanus (Tierra Data 2011, pp. 17-18). Prior to this survey, juveniles were only confirmed present in West Sycamore Canyon (Kassebaum 2010, pers. comm.).

Transplants

In addition to the seven currently remaining natural occurrences, in 2007,

Monardella viminea

was transplanted to four sites within the historical range of the species as a conservation measure to offset impacts associated with development of the Carroll Canyon Business Park. Three of the transplanted sites were in Carroll Canyon and the fourth in San Clemente Canyon (Ince 2010, p. 3). Most of the

M. viminea

transplants have experienced low survival rates, generally less than 20 percent, although one Carroll Canyon transplanted occurrence was reported to have a 44 percent survival rate (Service 2003, p. 25; Ince 2010, p. 8).

Summary of Factors Affecting

Monardella viminea

Section 4 of the Act and its implementing regulations (50 CFR 424) set forth the criteria for determining whether a species is endangered or threatened under the Act. A species may be determined to be an endangered or threatened species due to one or more of the five factors described in section 4(a)(1) of the Act: (A) The present or threatened destruction, modification or curtailment of its habitat or range; (B) overutilization for commercial, recreational, scientific, or educational purposes; (C) disease or predation; (D) the inadequacy of existing regulatory mechanisms; and (E) other natural or manmade factors affecting its continued existence. Listing actions may be warranted based on any of the above threat factors, singly or in combination. Each of these factors for

Monardella viminea

is discussed below.

A. The Present or Threatened Destruction, Modification, or Curtailment of Its Habitat or Range

Urbanization/Development

The original listing rule identified urban and residential development as a threat to

Monardella linoides

ssp.

viminea

(63 FR 54938; October 13, 1998). Prior to 1992, San Diego had grown by “a factor of 10 over the last 50 years” (Soule

et al.

1992, p. 39). At the time of listing, two large occurrences were located on private property and development proposals existed for one of these two parcels. Since listing, one of those two occurrences has been extirpated due to construction activities: EO 25 from the Carroll Canyon Business Park (CNDDB 2010a). Additionally, EO 14 in Murphy Canyon was believed extirpated after listing due to lingering impacts from construction activity near Highway 15 (CNDDB 2010a). Two occurrences at MCAS Miramar have been partially destroyed by road construction since the time of listing.

The Cities of San Diego and Santee have purchased private property as reserve land for

Monardella viminea.

Most occurrences are now found on land conserved or owned by MCAS Miramar, the City of San Diego, and the County of San Diego. Lands owned by the City and County of San Diego are covered by the MSCP, which is a habitat conservation plan (HCP) intended to maintain and enhance biological diversity in the San Diego region, and to conserve viable populations of endangered, threatened, and key sensitive species and their habitats (including

M. viminea

). The MSCP plan designates lands to be set aside for biological preserves. However, 20 percent of habitat for

M. viminea

occurs on privately owned land outside of the reserve areas. This habitat includes

M. viminea

occurrences in Sycamore and Spring Canyons (portions of EOs 8 and 26), and a transplanted occurrence where plants were removed for construction of the Carroll Canyon Business Park (Ince and Krantz 2008, p. 1). Any sites outside of the MSCP reserve areas are vulnerable to development; portions of Sycamore Canyon where

M. viminea

occurs were previously slated for development (Service 2003, pp. 1-23), though the project has been put on hold due to bankruptcy issues, and no development is scheduled (San Diego Business Journal 2011, pp. 1-3).

However, the occurrences discussed above represent only a small proportion of habitat that contains clumps of

Monardella viminea.

Seventy percent of land where

M. viminea

occurs is owned and managed by MCAS Miramar, and all remaining large occurrences (with more than 100 clumps of

M. viminea

) are found on MCAS Miramar. All canyon areas on the base are protected from development. Therefore, although urbanization does threaten some occurrences of

M. viminea,

the threat to the species' habitat is not significant across the range of the species, now or in the foreseeable future.

Sand and Gravel Mining

Sand and gravel mining has broad-scale disruptive qualities to native ecosystems (Kondolf

et al.

2002, p. 56). Sand and gravel mining was identified at the time of listing as adversely affecting

Monardella linoides

ssp

. viminea

(63 FR 54938; October 13, 1998). The larger of two occurrences (340 individuals) found on private land at the time of listing was identified as being threatened by sand and gravel mining, which was a threat that had the potential to eliminate or disrupt these local populations through changes in hydrology and elimination of individual plants. Since listing, all occurrences vulnerable to mining impacts have since been extirpated, either by altered drainage patterns or construction unrelated to mining operations (CNDDB 2010, EOs 3 and 25). Currently, we are not aware of any ongoing mining activities or any plans for future mining activities that would impact the species. While we may not be fully aware of all potential gravel mining activities on private lands, few

M. viminea

occurrences are on private land. Therefore, we do not consider sand and gravel mining to currently be a threat to

M. viminea,

nor a threat in the foreseeable future.

Altered Hydrology

The original listing rule identified altered hydrology as a threat to

Monardella linoides

ssp.

viminea,

particularly to portions of the habitat now considered to be in the range of

M. viminea

(63 FR 54938; October 13, 1998).

Monardella viminea

requires a natural hydrological system to maintain the secondary benches and streambeds on which it grows (Scheid 1985, pp. 30-31, 34-35). Upstream development can disrupt this regime, increasing storm runoff which can in turn erode the sandy banks and secondary benches upon which

M. viminea

grows. Floods also have the potential to wash away plants much larger than

M. viminea,

as has occurred in Lopez Canyon during heavy runoff following winter storms (Kelly and Burrascano 2001, pp. 2-3). This flood severely impacted the

M. viminea

occurrences in Lopez Canyon (Kelly and Burrascano 2006, pp. 65-69). Additionally, areas where altered hydrology caused decreased flows may experience an increase in invasion by nonnative species into creek beds, which can smother seedling and mature plants, and prevent natural growth of

M. viminea

(Rebman and Dossey 2006a, p. 12).

Changes in local and regional hydrology have had detrimental effects on

Monardella viminea.

Increases in surface and subsurface soil moisture (via direct effects to the water table associated with watershed urbanization) and changing streams from ephemeral to perennial adversely affect native plants adapted to a drier Mediterranean climate (cool moist winters and hot dry summers), such as

M. viminea.

Watershed urbanization alters the riparian vegetation community through changes in median and minimum daily discharges, dry season run-off, and flood magnitudes, specifically for Los Peñasquitos Creek and other locations (White and Greer 2006, pp. 133-136). Nonnative species incursion has been exacerbated by the changing water regime (underground hydrology), and

M. viminea

has been unable to adapt to the increased soil moisture (Burrascano 2007, pers. comm.).

Since listing, three occurrences have been extirpated due to altered hydrological patterns: Cemetery Canyon, Carroll Canyon, and western

San Clemente Canyon. All three of these occurrences are on city-owned or private land (CNDDB 2010a, EOs 3, 4, 11). On MCAS Miramar, watersheds on the undeveloped eastern half of the base, where most large occurrences of

Monardella viminea

are found, appear to have retained their natural hydrological regime (Rebman and Dossey 2006, p. 37). The only canyon on MCAS Miramar with substantial development and a historic occurrence of

M. viminea

is Rose Canyon. This location has lost all but one individual

M. viminea

(Rebman and Dossey 2006, p. 37).

Considering synergistic and cumulative effects of these combined hydrological threats, exacerbated by heavy development surrounding several canyons, we expect that altered hydrology will continue to pose a significant threat to habitats that support

Monardella viminea,

particularly outside the border of MCAS Miramar. We anticipate that this threat will continue into the foreseeable future.

Fire and Type Conversion

The listing rule mentioned that fuel modification to exclude fire could affect

Monardella linoides

ssp.

viminea

(63 FR 54938; October 13, 1998); the same is true of the reclassified

M. viminea

and its habitat. Otherwise, fire was not considered a severe threat to the species at the time of listing.

Our understanding of fire in fire-dependent habitat has changed since

Monardella linoides

ssp.

viminea

was listed in 1998 (Dyer 2002, pp. 295-296). Fire is a natural component for regeneration and maintenance of

M. viminea

habitat. The species' habitat needs concerning fire seem contradictory: A total lack of fire for long periods is undesirable, because the fires that eventually will occur can be catastrophic; yet re-introduction of fire (either accidentally or purposefully) is also undesirable, because such fires often become catastrophic as a result of previous lack of fire (

i.e.,

megafires). This conflicting situation has resulted from a disruption of the natural fire regime.

Fire frequency has increased in North American Mediterranean Shrublands in California since about the 1950s, and studies indicate that southern California has demonstrated the greatest increase in wildfire ignitions, primarily due to an increase in population density beginning in the 1960s, and thus increasing the amount of human-caused fires (Keeley and Fotheringham 2003, p. 240). Increased wildfire frequency and decreased return fire interval, in conjunction with other effects of urbanization, such as increased nitrogen deposition and habitat disturbance due to foot and vehicle traffic, are believed to have resulted in the conversion of large areas of coastal sage scrub to nonnative grasslands in southern California (Service 2003, pp. 57-62; Brooks

et al.

2004, p. 677; Keeley

et al.

2005, p. 2109; Marschalek and Klein 2010, p. 8). This type conversion (conversion of one type of habitat to another) produces a positive feedback mechanism resulting in more frequent fires and increasing nonnative plant cover (Brooks

et al.

2004, p. 677; Keeley

et al.

2005, p. 2109).

However, threats to the habitat from fire exclusion, which impacts processes that historically created and maintained suitable habitat for

Monardella viminea,

may make it even more vulnerable to extinction. The long-term ecological effects of fire exclusion have not been specifically detailed for

M. viminea;

however, we believe the effects of fire, fire suppression, and fire management in southern California habitats will be similar to that at locations in the Rockies, Cascades, and Sierra Nevada Mountains (Keane

et al.

2002, pp. 15-16). Fire exclusion in southern California habitat likely affects: (1) Nutrient recycling, (2) natural regulation of succession via selecting and regenerating plants, (3) biological diversity, (4) biomass, (5) insect and disease populations, (6) interaction between plants and animals, and (7) biological and biogeochemical processes (

i.e.,

soil property alteration)

(after Keane

et al.

2002, p. 8). Where naturally occurring fire is excluded, species that are adapted to fire (such as

M. viminea

) are often replaced by nonnative, invasive species that are better suited to the same areas in the absence of fire (Keane

et al.

2002, p. 9).

Some fire management is provided by CAL FIRE, which is an emergency response and resource protection department. CAL FIRE creates fire management plans to identify prevention measures that reduce risk, inform and involve the local communities in the area, and provide a framework to diminish potential wildfire losses and implement all applicable fire management regulations and policies (CAL FIRE 2011b; County of San Diego 2011a). CAL FIRE has signed a document to assist in management of backcountry areas in San Diego County, including Sycamore Canyon Ranch and its

Monardella viminea

occurrence (DPR 2009, p. 14; County of San Diego 2011, p. 1). However, the land protected under this agreement is only two percent of all

M. viminea

habitat.

Therefore, given the conversion of coastal sage scrub to nonnative grasses and the changing fire regime of southern California, we consider type conversion and the habitat effects of altered fire regime, particularly from increased frequency of fire, to be a significant threat to

M. viminea'

s habitat both now and in the foreseeable future.

Summary of Factor A

Monardella viminea

continues to be threatened by habitat loss and degradation by altered hydrological regimes that can result in uncontrollable flood events. Habitat of this species is also threatened by an unnatural fire regime resulting from manmade disturbance and activities, which in turn can cause invasion of the area by nonnative plants. Of the seven natural and four transplanted occurrences, those that are in areas where continued development is expected to occur may experience further alterations to hydrology and fire regimes. These threats to habitat are occurring now and are expected to continue into the foreseeable future.

B. Overutilization for Commercial, Recreational, Scientific, or Educational Purposes

To our knowledge, no commercial use exists for

Monardella viminea.

The listing rule suggested that professional and private botanical collecting could exacerbate the extirpation threat to the species due to botanists favoring rare or declining species (63 FR 54938; October 13, 1998). However, we are not currently aware of any interest by botanists in collecting

M. viminea.

Therefore, we do not believe that overutilization for commercial, recreational, scientific, or educational purposes constitutes a threat to this species now or in the foreseeable future.

C. Disease or Predation

Neither disease nor predation was known to be a threat affecting

Monardella linoides

ssp.

viminea

(63 FR 54938; October 13, 1998) at the time of listing. Volunteers have since noted grazing impacts to occurrences of

M. viminea

in Lopez Canyon (Kelly and Burrascano 2001, p. 5). However, this occurrence is the only documented location where grazing has occurred, and impacts were minimal. Therefore, based on the best available scientific and commercial information, neither disease nor herbivory constitute threats to

M. viminea

now or in the foreseeable future.

D. The Inadequacy of Existing Regulatory Mechanisms

At the time of listing, regulatory mechanisms that provided some protection for

Monardella linoides

ssp

. viminea

that apply to

Monardella viminea

included: (1) The Act in cases where

M. viminea

co-occurred with a Federally listed species; (2) the California Endangered Species Act (CESA); (3) the California Environmental Quality Act (CEQA); (4) implementation of conservation plans pursuant to California's Natural Community Conservation Planning Act; (5) land acquisition and management by Federal, State, or local agencies, or by private groups and organizations; and (6) local laws and regulations. The listing rule analyzed the potential level of protection provided by these regulatory mechanisms (63 FR 54938; October 13, 1998).

Currently,

Monardella linoides

ssp.

viminea

is listed as endangered under the Act (63 FR 54938; October 13, 1998). Provisions for its protection and recovery are outlined in sections 4, 7, 9 and 10 of the Act. This law is the primary mechanism for protecting

M. viminea,

which, as part of the original listed entity, currently retains protection under the Act. However, the protections afforded to

M. viminea

under the Act as part of

M. linoides

ssp.

viminea,

the currently listed entity, would continue to apply only if we determine to retain listed status for

M. viminea.

Therefore, for purposes of our analysis, we do not include the Act as an existing regulatory mechanism that protects

M. viminea.

We do note that

M. viminea

would likely continue to receive protection indirectly through habitat conservation plans (HCPs) approved under section10 of the Act and Natural Community Conservation Plans (NCCPs) approved under the State of California that will cover

M. viminea

even if the species is not Federally listed.

Federal Protections

National Environmental Policy Act (NEPA)

All Federal agencies are required to adhere to the National Environmental Policy Act (NEPA) of 1970 (42 U.S.C. 4321

et seq.

) for projects they fund, authorize, or carry out. The Council on Environmental Quality's regulations for implementing NEPA (40 CFR 1500-1518) state that in their environmental impact statements agencies shall include a discussion on the environmental impacts of the various project alternatives (including the proposed action), any adverse environmental effects which cannot be avoided, and any irreversible or irretrievable commitments of resources involved (40 CFR 1502). The NEPA itself is a disclosure law that provides an opportunity for the public to submit comments on a particular project and propose other conservation measures that may directly benefit listed species; however, it does not impose substantive environmental mitigation obligations on Federal agencies. Any such measures are typically voluntary in nature and are not required by the statute. Activities on non-Federal lands are also subject to NEPA if there is a Federal nexus.

Sikes Act

In 1997, section 101 of the Sikes Act (16 U.S.C. 670a(a)) was revised by the Sikes Act Improvement Act to authorize the Secretary of Defense to implement a program to provide for the conservation and rehabilitation of natural resources on military installations. To do so, the Department of Defense was required to work with Federal and State fish and wildlife agencies to prepare an integrated natural resources management plan (INRMP) for each facility with significant natural resources. The INRMPs provide a planning tool for future improvements; provide for sustainable multipurpose use of the resources, including activities such as hunting, fishing, trapping, and non-consumptive uses; and allow some public access to military installations. At MCAS Miramar and other military installations, INRMPs provide direction for project development and for the management, conservation, and rehabilitation of natural resources, including

M. viminea

and its habitat.

Approximately 70 percent of the remaining habitat for

Monardella viminea

occurs within MCAS Miramar. The Marine Corps completed an INRMP (2006-2010) with the advice of the Service (Gene Stout and Associates 2006, p. ES-2). The 2011-2014 INRMP is expected to be published by the military in the upcoming weeks. This new INRMP continues to benefit the species by spatially and temporally protecting known populations on MCAS Miramar, most of which are not fragmented. Over 99 percent of all

M. viminea

occurrences on the base occur in Type I or II management areas, where conservation of listed species, including

M. viminea,

is a priority (Gene Stout and Associates 2006, pp. 5-2, 5-5). MCAS Miramar manages invasive species, a significant threat to

M. viminea,

in compliance with Executive Order 13112, which states that Federal agencies must provide for the control of invasive species (Gene Stout and Associates 2006, p. 7-3). Invasive species management is a must-fund project to be carried out annually, following guidelines established in the National Invasive Species Management Plan (Gene Stout and Associates 2006, p. 7-7). This plan mandates control measures for invasive species through a combination of measures including pesticides and mechanical removal (National Invasive Species Council 2001, p. 37), thus providing a benefit by addressing type conversion that results following fires (see Factor A above). It also provides wildland fire management, including creation of fuelbreaks, a prescribed burning plan, and research on the effects of wildfire on local habitat types (Gene Stout and Associates 2006, pp. 7-8—7-9). As a result, MCAS Miramar is addressing threats related to the potential stress of fire on individual plants (see Factor E). Despite the benefits to

M. viminea

provided through the INRMP, the species continues to decline on MCAS Miramar, due likely to the synergistic effects of flood, reduced shrub numbers, and exotic species encroachment (type conversion) following the 2003 Cedar wildfire (Tierra Data 2011, p. 26).

State and Local Regulations

California's Native Plant Protection Act (NPPA) and Endangered Species Act (CESA)

Under provisions of NPPA (Division 2, chapter 10 section 1900

et seq.

of the California Fish and Game Code (CFG code)) and CESA (Division 3, chapter 1.5, section 2050

et seq.

of CFG code), the CDFG Commission listed

Monardella linoides

ssp.

viminea

as endangered in 1979. Currently, the State of California recognizes the State-listed entity as

M. viminea.

Both the CESA and NPPA include prohibitions forbidding the “take” of State endangered and listed species (Chapter 10, Section 1908 and Chapter 1.5, Section 2080, CFG code). With regard to prohibitions of unauthorized take under NPPA, landowners are exempt from this prohibition for plants to be taken in the process of habitat modification. When landowners are notified by the State that a rare or endangered plant is growing on their land, the landowners are required to notify CDFG 10 days in advance of changing land use in order to allow salvage of listed plants. Sections 2081(b) and (c) of CESA allow CDFG to issue incidental take permits for State-listed threatened species if:

(1) The authorized take is incidental to an otherwise lawful activity;

(2) The impacts of the authorized take are minimized and fully mitigated;

(3) The measures required to minimize and fully mitigate the impacts of the authorized take are roughly proportional in extent to the impact of the taking of the species, maintain the applicant's objectives to the greatest extent possible, and are capable of successful implementation;

(4) Adequate funding is provided to implement the required minimization and mitigation measures and to monitor compliance with and the effectiveness of the measures; and

(5) Issuance of the permit will not jeopardize the continued existence of a State-listed species.

The relationship between the NPPA and CESA has not been clearly defined under state law. The NPPA, which has been characterized as an exception to the take prohibitions of CESA, exempts a number of activities from regulation including: clearing of land for agricultural practices or fire control measures; removal of endangered or rare plants when done in association with an approved timber harvesting plan, or mining work performed pursuant to Federal or State mining laws, or by a public utility providing service to the public; or when a landowner proceeds with changing the use on their land in a manner that could result in take, provided the landowner notifies CDFG at least 10 days in advance of the change. These exemptions indicate that CESA and NPPA may be inadequate to protect

Monardella viminea

and its habitat, including from activities such as development/urbanization, altered hydrology or fuel modification.

California Environmental Quality Act (CEQA)

The California Environmental Quality Act (CEQA) (Public Resources Code 21000-21177) and the CEQA Guidelines (California Code of Regulations, Title 14, Division 6, Chapter 3, Sections 15000-15387) require State and local agencies to identify the significant environmental impacts of their actions and to avoid or mitigate those impacts, if feasible. The CEQA applies to projects proposed to be undertaken or requiring approval by State and local government agencies, and the lead agency must complete the environmental review process required by CEQA, including conducting an initial study to identify the environmental impacts of the project and determine whether the identified impacts are significant; if significant impacts are determined, then an environmental impact report must be prepared to provide State and local agencies and the general public with detailed information on the potentially significant environmental effects (California Environmental Resources Evaluation System 2010). “Thresholds of Significance” are comprehensive criteria used to define environmental significant impacts based on quantitative and qualitative standards and include impacts to biological resources such as candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the CDFG or the Service; or any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations, or by the CDFG or Service (CEQA Handbook, Appendix G, 2010). Defining these significance thresholds helps ensure a “rational basis for significance determinations” and provides support for the final determination and appropriate revisions or mitigation actions to a project in order to develop a mitigated negative declaration rather than an environmental impact report (Governor's Office of Planning and Research 1994, p. 5). Under CEQA, projects may move forward if there is a statement of overriding consideration. If significant effects are identified, the lead agency has the option of requiring mitigation through changes in the project or to decide that overriding considerations make mitigation infeasible (CEQA section 21002). Protection of listed species through CEQA is, therefore, dependent upon the discretion of the lead agency involved.

California's Natural Community Conservation Planning (NCCP) Act

The NCCP program is a cooperative effort between the State of California and numerous private and public partners with the goal of protecting habitats and species. An NCCP identifies and provides for the regional or area-wide protection of plants, animals, and their habitats, while allowing compatible and appropriate economic activity. The program began in 1991, under the State's NCCP Act (CFG Code 2800-2835). The primary objective of the NCCP program is to conserve natural communities at the ecosystem scale while accommodating compatible land uses (

http://www.dfg.ca.gov/habcon/nccp/

). Regional NCCPs provide protection to Federally listed species, and often unlisted species, by conserving native habitats upon which the species depend. Many NCCPs are developed in conjunction with HCPs prepared pursuant to the Act. The City and County of San Diego Subarea Plans under the MSCP are discussed below.

City of San Diego and County of San Diego Subarea Plans under the Multiple Species Conservation Plan (MSCP)

The MSCP is a sub-regional HCP and NCCP made up of several subarea plans that have been in place for more than a decade. Under the umbrella of the MSCP, each of the 12 participating jurisdictions is required to prepare a subarea plan that implements the goals of the MSCP within that particular jurisdiction. The sub-regional MSCP covers 582,243 ac (235,625 ha) within the county of San Diego. Habitat conservation plans and multiple species conservation plans approved under section 10 of the Act are intended to protect covered species by avoidance, minimization, and mitigation of impacts.

The MSCP Subarea Plan for the City of San Diego includes

Monardella viminea

(denominated as

M. linoides

ssp.

viminea

) as a covered species. The City's subarea plan designates land to be set aside for a biological preserve (City of San Diego 1997, p. 1-1). As of January 2011, less than 20 percent of all

M. viminea

occurrences were in the City of San Diego MSCP plan area (Service 2008, p. 10); the majority of the other occurrences are on lands owned by MCAS Miramar, with small numbers of clumps occurring on private and county-owned lands. Almost all occurrences that occur within the City of San Diego's MSCP Subarea Plan area have been protected in MSCP reserves and are annually monitored (City of San Diego 2010, p. 1). However, the management plan for the City of San Diego MSCP Subarea Plan has not been finalized; thus long-term management and monitoring provisions for this plant are not in place. Although management needs are frequently identified for

M. viminea,

the actions are not carried out on a regular basis to decrease threats to the plants, such as presence of nonnative vegetation and altered hydrology.

Within the City of San Diego MSCP Subarea Plan, further protections are afforded by the Environmentally Sensitive Lands ordinance (ESL). The ESL provides protection for sensitive biological resources (including

Monardella viminea

and its habitat), by ensuring that development occurs “in a manner that protects the overall quality of the resources and the natural and topographic character of the area, encourages a sensitive form of development, retains biodiversity and interconnected habitats, maximizes physical and visual public access to and along the shoreline, and reduces hazards due to flooding in specific areas

while minimizing the need for construction of flood control facilities,” thus providing protection against alteration of hydrology, a significant threat to

M. viminea.

The ESL was designed to act as an implementing tool for the City of San Diego Subarea Plan (City of San Diego 1997, p. 98).

The County of San Diego MSCP Subarea Plan covers 252,132 ac (102,035 ha) of unincorporated county lands in the southwestern portion of the MSCP plan area. Only two percent of

Monardella viminea

habitat occurs on County lands. The entirety of this habitat is included within the Sycamore Canyon Preserve established under the County of San Diego MSCP Subarea Plan. In 2009, a management plan was published for the preserve, with monitoring anticipated to begin in 2013. The plan specifically addresses

M. viminea

through removal of nonnative vegetation, habitat restoration, and implementation of a managed fire regime with a priority of protecting biological resources (DPR 2009, pp. 71, 76-77). Additionally, the plan mandates management to address the “natural history of the species and to reduce the risk of catastrophic fire,” possibly including prescribed fire (DPR 2009, p. 71); these measures address the stressor of fire on individual plants (Factor E) and the threat of type conversion due to frequent fire (Factor A).

Summary of Factor D

In determining whether

Monardella viminea

should be retained as a listed species under the Act, we analyze the adequacy of existing regulatory mechanisms without regard to current protections afforded under the Act. The majority (greater than 70 percent) of

M. viminea

occurrences are on MCAS Miramar. The base has developed and is implementing an INRMP under the Sikes Act to protect these occurrences (Factor E) and is addressing threats from type conversion due to frequent fire (Factor A). However, notwithstanding the benefit to

M. viminea

provided by the INRMP, the synergistic effects of flood, reduced shrub numbers, frequent fire, and nonnative species encroachment are resulting in a decline of

M. viminea

on the base (Factor E). While the INRMP does not eliminate threats to the species from megafire, we do not believe megafire impacts are susceptible to a regulatory fix.

The majority of

Monardella viminea

occurrences outside of MCAS Miramar are located within land owned by the City of San Diego, and they receive protection under the City of San Diego's MSCP Subarea Plan, which was approved under CESA and NCCP Act. The City of San Diego's MSCP Subarea plan provides protective mechanisms for

M. viminea

for proposed projects; these protective mechanisms are intended to address potential impacts that could threaten the species, such as development or actions that could result in altered hydrology. One such plan was developed for the city-owned land within West Sycamore Canyon. This land, a total of 21 ac (9 ha), was included within the development project entitled Sycamore Estates. This plan included monitoring of

M. viminea

occurrences within West Sycamore Canyon and provisions to prevent altered hydrology to areas containing

M. viminea

through construction of mechanisms such as silt fences to prevent erosion and subsequent alteration of channel structure (T&B Planning Consultants 2001, pp. 136, 166). However, Sycamore Estates was never completed (see Factor A), and no monitoring has taken place in West Sycamore Canyon. Therefore, the plan addressing construction on Sycamore Estates is not currently protecting

M. viminea.

The City of San Diego Subarea Plan also includes provisions for monitoring and management through development of location-specific management plans for preserve land. However, the City of San Diego MSCP Subarea Plan has not developed final monitoring and management plans for

M. viminea.

As a result, even though occurrences of

M. viminea

are monitored on a yearly basis and management needs for

M. viminea

habitat are identified, conservation measures to ameliorate immediate and significant threats to the species from nonnative species and alteration of hydrology are not actively being implemented because the management plans are not yet in place. With regards to lands covered by the County of San Diego MSCP Subarea Plan (two percent of the species' habitat), regulatory mechanisms are in place to conserve and manage

Monardella viminea.

Despite the protections afforded to

Monardella viminea

under the Sikes Act through the INRMP for MCAS Miramar and the protections afforded under the City of San Diego and County of San Diego plans, we conclude that existing regulatory mechanisms at this time are inadequate to alleviate the threats to this species in the absence of the protections afforded by the Act.

E. Other Natural or Manmade Factors Affecting Its Continued Existence

Trampling

Trampling was identified as a threat to

Monardella linoides

ssp.

viminea

in the listing rule (63 FR 54938; October 13, 1998). Trampling of

M. viminea

occurs via human travel through the habitat of the species. This factor has not been quantified, and to date is only suspected to be a threat to

M. viminea

via direct mortality and increasing rates of erosion (Service 2008, p. 11). Trampling on private lands cannot currently be controlled and could impact populations located on private lands; however, few occurrences are located on private lands, and we have no evidence of trampling-related mortality. Therefore, we do not consider trampling to be a significant threat across the range of the species.

Nonnative Plant Species

The listing rule identifies nonnative plants as a threat to

Monardella linoides

ssp.

viminea

(63 FR 54938; October 13, 1998); this threat is ongoing for the occurrences of the listed entity now considered to be

M. viminea.

San Diego County habitats have been altered by invasion of nonnative species (Soule

et al.

1992, p. 43). Nonnative grasses, which frequently out-compete native species for limited resources and grow more quickly, can smother seedling and mature

M. viminea

and prevent natural growth (Rebman and Dossey 2006a, p. 12). Nonnative plants also have the potential to lower water tables and alter rates of sedimentation and erosion by altering soil chemistry, nutrient levels, and the physical structure of soil. As such, they can often out-compete native species such as

M. viminea

(Kassebaum 2007, pers. comm.). Nonnative plants also alter frequencies, size, and intensity of fires (flame duration and length, soil temperature during a fire, and after-effects of long-term porosity and soil glassification, in which high heat causes silica particles in the soil to fuse together to form an impermeable barrier) (Vitousek

et al.

1997, pp. 8-9; Arno and Fielder 2005, p. 19).

When the processes of natural disturbance, such as fire regime and normal storm flow events, are altered, native and nonnative plants can overcome otherwise suitable habitat for

Monardella viminea

(Kassebaum 2007, pers. comm.). At least four occurrences of

M. viminea

are believed to have been extirpated since listing due in part to invasion of native and nonnative plant species (CNDDB 2010a; EOs 11, 12, 13, and 15). Nonnative plants are present throughout all canyons on MCAS Miramar where

M. viminea

occurs, occupying areas that might instead be colonized by

M. viminea

seedlings (Tierra Data 2011, p. 29). Areas heavily invaded by nonnative grasses have fewer adult

M. viminea

plants than areas

free from invasion, or feature adult plants that have been reduced in size after the encroachment of nonnative species (Tierra Data 2011, p. 29). Additionally, one occurrence monitored by the City of San Diego has undergone a rapid increase in nonnative plant cover, climbing from 26 percent in 2008 to 71 percent in 2010 (City of San Diego 2008, p. 1; City of San Diego 2010, p. 11).

Due to the absence or alteration of the natural disturbance processes within the range of

Monardella viminea

that has caused competition for space and nutrients, increased fire intensity, and extirpation of

M. viminea

occurrences since listing, we consider nonnative plant species to be a significant factor threatening the continued existence of the species, both now and in the foreseeable future.

Small Population Size and Restricted Range

The listing rule identified the restricted range and small population size of

Monardella linoides

ssp.

viminea

as threats. These conditions increase the possibility of extinction due to chance events, such as floods, fires, or drought, beyond the natural variability of the ecosystem (Lande 1993, p. 912; 60 FR 40549, August 9, 1995). Chance or stochastic events have occurred in the range of

M. viminea,

and it is very possible that these events may continue to make

M. viminea

vulnerable to extinction, because of

M. viminea's

small numbers and limited range. Of the 20 occurrences of

M. viminea

known at the time of listing, 5 had fewer than 100 individuals. None of the smallest five populations were protected at the time of listing, and all have since been extirpated due to competition with nonnative grasses, construction, or unknown reasons (CNDDB 2010). As stated earlier, only 7 natural occurrences remain. Currently, despite their protection on reserve lands, many of the largest occurrences with multiple clumps and the healthiest-looking leaves and flowers are still declining in number.

In particular, small population size makes it difficult for

Monardella viminea

to persist while sustaining the impacts of fire, altered hydrologic regimes, and competition with nonnative plants. Prior to the 2008 5-year review, monitoring of the MCAS Miramar occurrences indicated that the population had declined significantly for unknown reasons that could not be clearly linked to the cumulative impacts of fire, herbivory, or hydrological regimes (Rebman and Dossey 2006a, p. 14). Since the 2006 surveys by Rebman and Dossey at MCAS Miramar, plants damaged in the 2003 fire have resprouted from the root. Despite the fact that plants have resprouted, biological monitors at MCAS Miramar report that the decline continues and the cause is unknown, with 45 percent of the population on MCAS Miramar lost since 2002 (Kassebaum 2010, pers. comm.; Tierra Data 2011, p. 12). No empirical information is readily available to estimate the rate of population decrease or time to extinction for

M. viminea;

however, its habitat and population have decreased since the time of listing. Therefore, based on the best available scientific information, we consider that small population size and the declining trend of

M. viminea

exacerbate the threats attributable to other factors.

Fire

Although the habitat occupied by

Monardella viminea

is dependent upon some form of disturbance to reset succession processes (such as periodic fire and scouring floods), we considered whether megafire events have the potential to severely impact or eliminate populations by killing large numbers of individual plants, their underground rhizomes (stems), and the soil seed bank. Also, severe fire could leave the soil under hydrophobic conditions, in which the soil becomes water-repellant, often resulting in plants receiving an inadequate amount of water (Agee 1996, pp. 157-158; Keane

et al.

2002, p. 8; Keeley 2001, p. 87; Arno and Fiedler 2005, p. 19).

Recently, San Diego County has been impacted by multiple large fire events, a trend that is expected to continue. A model by Snyder

et al.

(2002, p. 9-3) suggests higher average temperatures for every month in every part of California, which would create drier, more combustible fuel types. Also, Miller and Schlegel (2006, p. 6) suggest that Santa Ana conditions (characterized by hot dry winds and low humidity) may significantly increase during fire season under global climate change scenarios. Small escaped fires have the potential to turn into large fires due to wind, weather conditions of temperature and humidity, lack of prescribed fires to control fuels, invasive vegetation, and inadequate wildfire control/prevention. For example, the October 2007 Harris fire in San Diego County burned 20,000 acres (ac) (8,094 hectares (ha)) within 4 hours of ignition (California Department of Forestry 2008, p. 57). Another fire near Orange, California, turned into a large size-class fire in less than 12 hours, and an unattended campfire set off the June 2007 Angora fire near Lake Tahoe in northern California, which spread 4 miles (6.4 kilometers) in its first 3 hours, and burned over 3,000 ac (1,214 ha) (USDA 2007, p. 1).

A narrow endemic such as

Monardella viminea

could be especially sensitive to megafire events. One large fire could impact all or a large proportion of the entire area where the species is found, as occurred in the 2003 Cedar Fire, where 98 percent of occurrences on MCAS Miramar and

M. viminea

clumps in the privately owned portions of Sycamore Canyon burned. However, despite the overlap of the Cedar Fire with

M. viminea

occurrences on MCAS Miramar, the decline of the burned occurrences of

M. viminea

was not as severe as initially expected, as plants were later able to resprout from the root. Additionally, new juveniles and seedlings documented by the 2009 survey occurred primarily on lands burned by the 2003 Cedar Fire (Tierra Data 2011, p. 16).

Given the increased frequency of megafires within Southern California ecosystems, and the inability of regulatory mechanisms to prevent or control megafire, we find that megafire does have the potential to impact occurrences of

Monardella viminea.

However, given

M. viminea's

persistence through past fires and its ability to recover from direct impact by fires, we do not find that megafire is a significant threat to individual

M. viminea

plants now, nor is likely to become a significant threat in the foreseeable future. However, as noted in the Factor A discussion above, we do find that type conversion due to altered fire regime and megafire are threats to the habitat that supports

M. viminea.

Climate Change

A broad consensus exists among scientists that the earth is in a warming trend caused by anthropogenic greenhouse gases such as carbon dioxide (IPCC 2007). Researchers have documented climate-related changes in California (Croke

et al.

1998, pp. 2128, 2130; Breshears

et al.

2005, p. 15144). Predictions for California indicate prolonged drought and other climate-related changes will continue in the future (Field

et al.

1999, pp. 8-10; Lenihen

et al.

2003, p. 1667; Hayhoe

et al.

2004, p. 12422; Breshears

et al.

2005, p. 15144; Seager

et al.

2007, p. 1181; IPCC 2007, p. 9). Models are not yet powerful enough to predict what will happen in localized regions, such as southern California, but many scientists believe warmer, wetter winters and warmer, drier summers will occur within the next century (Field

et al.

1999, pp. 2-3, 20). The impacts on

species like

Monardella viminea,

which depend on specific hydrological regimes, may be more severe (Graham 1997, p. 2).

Since approximately the time of listing in 1998, an extended drought in the region (San Diego County Water Authority 2010, p. 2) created unusually dry habitat conditions. From 2000 to 2009, at one of the closer precipitation gauges to the species' range (Lake Cuyamaca, San Diego County, California), 8 of 10 years had precipitation significantly below normal (San Diego County Water Authority 2010, p. 2). This extended drought has cumulatively affected moisture regimes, riparian habitat, and vegetative conditions in and around suitable habitat for

Monardella viminea,

and thus increased the stress on individual plants. As stated above, predictions indicate that future climate change may lead to similar, if not more severe, drought conditions.

The predicted future drought could impact the dynamic of the streambeds where

Monardella viminea

grows. Soil moisture and transportation of sediments by downstream flow have been identified as key habitat features required by

M. viminea.

The species is characterized as being associated with areas of standing water after rainfall (Elvin and Sanders 2003, p. 426). Monitors for the City of San Diego have observed decreased plant health and increased dormancy of

Monardella

species in years with low rainfall (City of San Diego 2003, p. 3; City of San Diego 2004, p. 3). Specific analyses of population trends as correlated to rainfall are difficult due to inconsistent plant count methods (City of San Diego 2004, p. 67).

Additionally, drier conditions may result in increased fire frequency. As discussed under Factors A and E, this could make the ecosystems in which

Monardella viminea

currently grows more vulnerable to the threats of subsequent erosion and invasive species. In a changing climate, conditions could change in a way that would allow both native and nonnative plants to invade the habitat where

M. viminea

currently occurs (Graham 1997, p. 10).

While we recognize that climate change and increased drought associated with climate change are important issues with potential effects to listed species and their habitats, the best available scientific information does not currently give evidence specific enough for us to formulate accurate predictions regarding its effects to particular species, including

Monardella viminea.

Therefore, we do not consider global climate change a current threat to

M. viminea,

now or in the foreseeable future.

Summary of Factor E

Based on a review of the best available scientific and commercial data regarding trampling, nonnative plant species, megafire, climate change, and small population size and restricted range, we found that nonnative plant species pose a significant threat to

Monardella viminea.

Additionally, the small population size and restricted range of

M. viminea

could exacerbate threats to the species. We found no other evidence that trampling or other natural or manmade factors pose a significant threat to

M. viminea,

either now or in the foreseeable future. We conclude based on the best available scientific information that

M. viminea

could be affected by fire impacts associated with the death of individual plants; however, we do not consider this a significant threat to the continued existence of the species. Finally with regard to the direct and indirect effects of climate change on individual

M. viminea

plants and its habitat, we have no information at this point to demonstrate that predicted climate changes poses a significant threat to the species either now or in the foreseeable future.

Proposed Determination—

Monardella viminea

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to

Monardella viminea.

As described above, we find that threats attributable to Factor A (The Present or Threatened Destruction, Modification, or Curtailment of Its Habitat or Range) represent significant threats to

M. viminea,

particularly through severe alteration of hydrology in Carroll, Lopez, and San Clemente Canyons. Additionally, type conversion and habitat degradation due to frequent fire represent a significant and immediate threat to the species across its range. We also find that, in the absence of the Act, other existing regulatory mechanisms as described under Factor D would not provide protections adequate to alleviate threats to

M. viminea.

Finally, we find that threats attributable to Factor E (Other Natural or Manmade Factors Affecting Its Continued Existence) represent significant threats to the species throughout its range, including impacts from nonnative plant species invading canyons where

M. viminea

exists. Additionally, the small population size of

M. viminea

could exacerbate the threats to the species. Furthermore, the synergistic effects of flood, reduced shrub numbers, frequent fire, and nonnative species encroachment pose an increased risk to the species, resulting in continued population decline such as that seen on MCAS Miramar in recent years.

When the species was listed in 1998, there were 18 extant occurrences of what we now consider to be

Monardella viminea;

currently, there are only 7 known natural occurrences of

M. viminea.

All seven of these occurrences have continued to decline since listing and since the most recent (2008) 5-year review. Since the recent taxonomic revision of

Monardella linoides

ssp.

viminea

into two separate species, we now know that both the number of clumps and the limited geographic range of

M. viminea

are substantially less than originally thought, as two of the occurrences at time of listing are now considered to be

M. stoneana.

As discussed above, natural occurrences of

M. viminea

occur in only six watersheds in a very limited area of San Diego County. Transplanted occurrences occur in two additional canyons; however, over the past 3 years, survival of three of the transplanted sites is below 20 percent, with the fourth at only 44 percent (Ince 2010, p. 8). Additionally, the most recent surveys from MCAS Miramar, which holds the majority of the largest occurrences, have shown a rapid decline of the species over the past 7 years (Tierra Data 2011, p. 12).

The Act defines an endangered species as any species that is “in danger of extinction throughout all or a significant portion of its range” and a threatened species as any species “that is likely to become endangered throughout all or a significant portion of its range within the foreseeable future.” Given the rapid population decline (particularly the decline of 45 percent of the population on MCAS Miramar since 2002), the species' limited range and small population size, and continuing significant threats, we find that

Monardella viminea

is in danger of extinction throughout its range. Therefore, endangered status under the Act continues to be warranted for

M. viminea.

Status Review—

Monardella stoneana

Species Description

Monardella stoneana

is a perennial herb or subshrub in the Lamiaceae (mint family) with a woody base and aromatic leaves. The sparsely pubescent multiple stems bear sparsely gland-dotted broadly lanceolate to lance-ovate leaves, and dense, terminal clusters of pale

pink flowers. The leaves are 0.6-1.2 in (15-30 mm) long by 0.2-0.4 in (4-10 mm) wide, and the middle flower bracts are 0.3-0.4 in (7-10 mm) long (Elvin and Sanders 2003, pp. 426, 431-432).

Monardella stoneana

often grows together in clumps of one to four individual plants. As the number of plants within a clump cannot be reliably distinguished without exposing the roots, the species is usually counted by clumps rather than as individual plants.

Habitat

Monardella stoneana

occurs in cypress forest and chaparral habitats on banks of ephemeral washes in canyons where surface water flows for usually less than 48 hours after a rain event (Elvin and Sanders 2003, p. 430; SANDAG 1995). It is often found with

Baccharis sarothroides

(broom baccharis) and Cupressus (cypress) species (CNDDB 2010b). It is most commonly found in canyon bottoms and north-facing slopes, and along bends of meandering drainages (Elvin and Sanders 2003, p. 426). Many of the streams where

M. stoneana

grows hold water for up to several months during the rainy season (Elvin and Sanders 2003, p. 426).

Monardella stoneana

is found on rockier substrate than

M. viminea,

often between spaces in stones or boulders along the creek bed (Elvin and Sanders 2003, p. 426; City of San Diego 2005, p. 3; City of San Diego 2008, p. 4).

The chaparral habitat that

Monardella stoneana

favors benefits from small or managed fires that clear out dead or encroaching scrub vegetation and reduce nonnative species (Minnich 1983, p. 1290). Chaparral is more resistant to fire than coastal sage scrub, due to strong recruitment and effective germination after repeated fire events (Keeley 1987, p. 439; Tyler 1995, p. 1009). As with

M. viminea,

there are two ways in which fire can negatively impact

M. stoneana.

First, an increased frequency of fires of all sizes can result in type conversion or invasion of nonnative grasses into chaparral habitats that can choke out native vegetation, including shrubs associated with

M. stoneana.

This is a habitat-based effect. Second, large or unmanaged fires (megafire) can be a particular threat to a narrow endemic species like

M. stoneana

because a single megafire could eliminate a large proportion of individual plants within the extant range of the species. Rebman and Dossey (2006b, p. 2) reported that

M. viminea

is capable of resprouting after fire; we expect the same to be true of

M. stoneana.

Additional information is needed on the role of fire in

M. stoneana

habitat, particularly within riparian portions of canyons, and the effects of fire on clumps of

M. stoneana.

Please see our request for information in the Public Comments section above.

Life History

Very little is known about the germination and establishment of

Monardella stoneana.

Mature plants of the closely related

M. viminea

flower readily, with inflorescences persisting for 10 to 12 weeks (Elvin and Sanders 2003, pp. 430-431). Plants are short-lived perennials producing a new cohort of aerial stems each year from a persisting perennial root structure. Plants of this species are not known to be rhizomatous; however, root masses may become separated over time, resulting in adjacent genetically identical but separate plants.

No pollination studies are known to exist for

Monardella stoneana;

however, other

Monardella

taxa are visited by butterfly and bee species (Elvin 2003, p. 2). Bees collected from the closely related

M. linoides

include wasp-like bees (

Hylaeus

sp.), mason bees (

Osmia

spp. or

Chalicodoma

spp.), and miner bees (

Anthophora

spp.) (Hurd 1979, pp. 1762, 1765, 2042, 2073, and 2164). Successful reproduction of flowering plants depends on pollinator abundance and effectiveness (Javorek

et al.

2002, p. 350). Therefore, pollinator movement and availability should be considered when assessing likely population distributions and survival, and habitat needs of

M. stoneana.

Geographic Range and Status

Monardella stoneana

is a geographically narrow endemic restricted to southwestern San Diego County, in the United States, and to northern portions of Baja California, Mexico (Figure 1). All eight extant occurrences and one extirpated occurrence (Table 1) are found in the vicinity of Otay Mesa, Otay Mountain, and Tecate Peak (CNDDB 2010b).

Monardella stoneana

occurs on lands owned by the BLM, the City of San Diego, the State of California, the CDFG, and lands under private ownership. The use of the word occurrence, as described in the

Geographic Range and Status

section for

M. viminea,

also applies to

M. stoneana.

A total of two occurrences now considered

Monardella stoneana

were known and extant at the time of listing (63 FR 54938; October 13, 1998). According to the most recent report from the CNDDB, eight occurrences of

M. stoneana

are currently extant, with additional clumps easily visible in Mexico just across the border from California (CNDDB 2010b, EOs 7, 8). Due to the rarity of juveniles of this species and the closely related

M. viminea,

and the fact that most occurrences were discovered less than 5 years after listing, we believe all occurrences were extant at the time of listing.

There is little information available on the population trends of most

Monardella stoneana

occurrences since listing. Only two EOs receive regular monitoring, EO 1 (Marron Valley) and EO 5 (Buschalaugh Cove). The Buschalaugh Cove occurrence, located on land owned by the City of San Diego, declined from two clumps in 2004 to one clump in 2006, and then no clumps in 2008 (City of San Diego 2004, p. 3; City of San Diego 2006, p. 8; City of San Diego 2008, p. 2). The last remaining clump at this occurrence was burned as a result of the 2007 Harris Fire and has not been located by monitors since that time (City of San Diego 2008, p. 2; City of San Diego 2009, p. 2; City of San Diego 2010, p. 256). The Marron Valley occurrence, also located on land owned by the City of San Diego, appears to have declined slightly from 120 individuals in 2002, to 95 in 2010 (City of San Diego 2010a, p. 238; City of San Diego 2010b, p. 2). However, the City of San Diego acknowledges that its monitoring methods are not always consistent across years (City of San Diego 2005, pp. 2-3), so the differences could be an artifact of inconsistencies in monitoring. Since 2005, the population has remained steady at 95 plants (City of San Diego 2010b, p. 2).

Little information is available on the other occurrences. Reports from the CNDDB state that the Otay Lakes occurrence declined from 200 clumps in 1989, to 25 plants in 2005 (EO 4; CNDDB 2010b, p. 4); these are the only two surveys we are aware of for this occurrence. According to the CNDDB, all other occurrences are still extant (CNDDB 2010b). No surveys have been conducted in Mexico; the only known occurrences in Mexico are those visible across the border, as discussed above.

Summary of Factors Affecting

Monardella stoneana

As stated above in the Summary of Factors Affecting

Monardella viminea

section, the original listing rule for the

M. linoides

ssp

. viminea

contained a discussion of these five factors, as did the 2008 5-year review. However, the reader must bear in mind that both of these documents included discussions regarding

M. linoides

ssp.

viminea,

without separation, or recognition of

M. stoneana

M. viminea.

Below, each of

the five listing factors is discussed for

M. stoneana

specifically.

A. The Present or Threatened Destruction, Modification, or Curtailment of Its Habitat or Range

Urbanization/Development

The original listing rule identified urban development as one of the most important threats to

Monardella linoides

ssp.

viminea

(63 FR 54938; October 13, 1998). However, the urbanization and development threats described in the 1998 listing rule apply only to those occurrences now attributable to

M. viminea.

Monardella stoneana

occurs almost entirely on publicly owned land managed by the BLM (approximately 34 percent), CDFG (approximately 55 percent), or City of San Diego (approximately 7 percent). These occurrences are protected from habitat destruction or modification due to urban development because they are conserved and managed within the BLM's Otay Mountain Wilderness or the City of San Diego's and CDFG's preserves under the MSCP; this contrasts with

M. viminea

occurrences conserved by the City of San Diego that do not have management plans (see also Factor D discussion below and Factor D discussion for

M. viminea

The

Monardella stoneana

occurrences located on the two sections of land owned by the City of San Diego have been set aside for conservation purposes and are undevelopable. The one occurrence located on private land at the Otay Lakes site is contained within lands set aside as part of the Otay Ranch Preserve, and thus protected from development. Based on the lack of threats from development on land currently occupied by

M. stoneana,

we do not believe that urban development is a threat to this species now, nor will it be in the foreseeable future, within the United States. While we are not aware of any proposed development in areas occupied by

M. stoneana

in Mexico, we are also not aware of the extent of the species' distribution in Mexico. Thus, the best scientific evidence does not support urbanization as a significant threat to

M. stoneana

in Mexico.

Sand and Gravel Mining

Sand and gravel mining activities were identified as threats to

Monardella linoides

ssp.

viminea

in the 1998 listing rule and the recent 5-year review (63 FR 54938, October 13, 1998; Service 2008). As was the case for urban development, the threats described in the 1998 listing rule apply only to those occurrences now attributable to

M. viminea.

We are not aware of any historical mining that has impacted occurrences of

M. stoneana,

nor are we aware of any plans for future mining activities that may impact the species. Therefore, we believe that sand and gravel mining activities do not pose a threat to the continued persistence of

M. stoneana.

Altered Hydrology

The original listing rule identified altered hydrology as a threat to

Monardella linoides

ssp

. viminea

(63 FR 54938; October 13, 1998).

Monardella viminea

depends on a natural hydrological system to maintain the secondary alluvial benches and streambeds on which it grows (Scheid 1985, pp. 30-31, 34-35); we believe the closely related

M. stoneana

does as well. Upstream development can disrupt this regime by increasing storm runoff, which can result in erosion of stream banks and rocky cobble upon which

M. stoneana

grow. Floods also have the potential to wash away plants much larger than

M. stoneana,

as has occurred with

M. viminea

in Lopez Canyon (Kelly and Burrascano 2001, pp. 2-3). On the other hand, decreased flows increase the possibility of invasion by nonnative species into the creek bed, which can smother seedling and mature plants and disrupt growth processes (Rebman and Dossey 2006a, p. 12).

Habitat characteristics for

Monardella stoneana

have not been described in detail, but, as with

M. viminea,

alteration of hydrology may disrupt the natural processes and habitat characteristics that support

M. stoneana.

However,

M. stoneana

reportedly “most often grows among boulders, stones, and in cracks of the bedrock of these intermittent streams in rocky gorges” (Elvin and Sanders 2003, p. 429), which suggests the habitat of

M. stoneana

may be largely resistant to erosion events. More importantly, given the lack of urban development in the Otay area where the majority of the plants occur, substantial alteration of hydrology has not occurred to date and is not expected to occur in the foreseeable future, and is thus not a threat to

M. stoneana.

Fire and Type Conversion

As discussed under Factor A for

Monardella viminea,

our understanding of the role of fire in fire-dependent habitat has changed since the time of listing, and the intensity of wildfire and frequency of megafires has increased compared to historical regimes. However,

M. stoneana

is associated with different habitat types than

M. viminea.

While

M. viminea

occurs in coastal sage scrub and riparian scrub,

M. stoneana

is found primarily in chaparral habitats.

Chaparral is more resistant to fire than coastal sage scrub, due to strong recruitment and effective germination after repeated fire events (Keeley 1987, p. 439; Tyler 1995, p. 1009). Chaparral is considered a crown-fire ecosystem, meaning ecosystems which “have endogenous mechanisms for recovery that include resprouting from basal burrs and long-lived seed banks that are stimulated to germinate by fire” (Keane

et al.

2008, p. 702). These ecosystems are also resilient to high-intensity burns (Keeley

et al.

2008, p. 1545).

The fire regime in Baja California, Mexico, where some

Monardella stoneana

occurs, has not undergone the same fire suppression activities that have occurred in the United States. Some researchers claim that the fire regime of chaparral growing in Baja California is thus not affected by megafires due to a lack of fire suppression activities (Minnich and Chou 1997, Minnich 2001). Nevertheless, Keeley and Zedler (2009, p. 86) believe that the fire regime in Baja California still mirrors that of Southern California, similarly consisting of “small fires punctuated at periodic intervals by large fire events” Therefore, we expect that impacts from fire in Baja California will be similar to that in San Diego County.

Despite the resiliency of chaparral ecosystems to fire events, chaparral, like coastal sage scrub, has been experiencing type conversion in many areas in southern California. As with coastal sage scrub, chaparral habitat is also being invaded by nonnative species (Keeley 2006, p. 379). Nonnative grasses sprout more quickly after a fire than chaparral species; this process is exacerbated by increased fire intervals (Keeley 2001, pp. 84-85).

However, monitoring data from the MSCP Rare Plant Field Surveys by the City of San Diego indicate that type conversion is not taking place in chaparral habitats surrounding occurrences of

Monardella stoneana.

For the past decade, the City of San Diego has been monitoring the occurrences of

M. stoneana

on City lands, documenting their general habitats and assessing disturbances and threats. In the City of San Diego 2006 report, the Otay Lakes occurrence of

M. stoneana

(one clump comprised of two individuals) was reported as having “fair to good” habitat, with monitors noting that threats occurred, such as encroachment of tamarisk (

Tamarisk

spp.) and other nonnative plants (10 percent cover), and immigrant trails

(City of San Diego 2006, p. 8). This occurrence was lost after the 2006 survey, as described in the

Geographic Range and Status

section of this proposed rule. Although the 2008 and 2010 survey reports for the Otay Lakes site describe habitat disturbances such as type conversion due to fire frequency and invasive species (particularly nonnative grasses) (City of San Diego 2008, p. 2; City of San Diego 2010, p. 5), the surveys also indicate that the percent cover of native species has increased from 2008 to 2010 (from 23 to 42 percent), while the percent cover of nonnative species has increased (from 30 to 44 percent) (City of San Diego 2008, p. 1; City of San Diego 2010; p. 5). The most recent survey report (2010) described the habitat at this site as “fair to good” (City of San Diego 2010, p. 254).

For the Marron Valley site, the MSCP Rare Plant Field Surveys conducted by the City of San Diego recorded 95 individuals of

Monardella linoides

ssp.

viminea

(now

M. stoneana

) in its 2006 survey report, which was unchanged in survey results from 2008 to 2010 (City of San Diego 2006, p. 1; City of San Diego 2008, p. 1; City of San Diego 2009, p.1; City of San Diego, p. 5). Habitat at the Marron Valley site was characterized as “fair to good” for 2008 through 2010 (City of San Diego 2008, p. 2; City of San Diego 2010, p. 11). As with the Otay Lakes location, type conversion due to frequent fire (Factor A) and invasion of nonnative grasses was described as a disturbance/stressor to the

M. stoneana

habitat (City of San Diego 2008, p. 2; City of San Diego 2009, p. 2). Nonetheless, recent surveys indicate that the percent ground cover by native species at the Marron Valley site (EO 1) has increased from 2008 to 2010 (from 26 to 32 percent), while the percent ground cover by nonnative species has also increased (from 15 to 22 percent) (City of San Diego 2008, p. 1; City of San Diego 2010; p. 5). While no habitat assessment surveys are available for other

M. stoneana

occurrences on Otay Mountain or near Tecate Peak, we would expect the results to be similar to those from the Marron Valley and Otay Lakes occurrences, as they occur in the same or similar habitat types (SANDAG 1995).

Zedler

et al.

(1983, p. 816) concluded that short-interval fires on Otay Mountain will lead to an increase in herbs and subshrubs given their observation that the “common pattern after chaparral fires, like that of 1979 [on Otay Mountain], is for native and introduced annual herbs to dominate for the 1st yr and then gradually decline as the cover of shrub and subshrubs inceases [sic].” Additionally, monitoring data for

Monardella stoneana

has not recorded the same rapid increases in nonnative vegetation as have occurred in habitat where

M. viminea

grows (City of San Diego 2008, p. 1; City of San Diego 2009; p. 1). While several

M. viminea

occurrences have been extirpated due to invasion of nonnative vegetation (see Factor A discussion for

M. viminea

above), no occurrences of

M. stoneana

have been similarly affected.

Nonetheless, fire is still a stressor to

Monardella stoneana

habitat and many other sensitive habitats throughout southern California. To this end, on land owned and managed by the CDFG and BLM, which contain approximately 88 percent of all occurrences of

M. stoneana,

fire management is provided by CAL FIRE. CAL FIRE is an emergency response and resource protection department. The CAL FIRE protects lives, property, and natural resources from fire, and it protects and preserves timberlands, wildlands, and urban forests. The CAL FIRES's varied programs work together to plan protection strategies incorporating concepts of the National Fire Plan, the California Fire Plan, individual CAL FIRE Unit Fire Plans, and Community Wildfire Protection Plans (CWPPs). Fire Plans outline the fire situation within each CAL FIRE Unit, and CWPPs do the same for communities (CAL FIRE 2011a, p. 1; County of San Diego 2011a). Each plan identifies prevention measures to reduce risks, informs and involves the local communities in the area, and provides a framework to diminish potential wildfire losses and implement all applicable fire management regulations and policies (CAL FIRE 2011b; County of San Diego 2011a). Planning includes other State, Federal, and local government agencies as well as Fire Safe Councils (CAL FIRE 2011a, p. 1). Cooperative efforts via contracts and agreements between State, Federal, and local agencies are essential to respond to wildland fires (CAL FIRE 2011a, p. 1). Because of these types of cooperative efforts, fire engines and crews from many different agencies may respond at the scene of an emergency (CAL FIRE 2011a, p. 1); however, CAL FIRE typically takes the lead with regard to planning for megafire prevention, management, and suppression, and CAL FIRE is in charge of incident command during a wildfire.

The San Diego County Fire Authority (SDCFA), local governments, and CAL FIRE cooperatively protect 1.42 million ac (0.6 million ha) of land with 54 fire stations throughout San Diego County (County of San Diego 2011b, p. 1). Wildfire management plans and associated actions can help to reduce the impacts of type conversion due to frequent fire on natural resources, including

M. stoneana.

Therefore, based on the best available scientific and commercial information, type conversion due to more frequent fire does not pose a threat to

M. stoneana

or its associated plant communities now or in the foreseeable future. The stress of frequent fire on

M. stoneana

is further alleviated by management actions undertaken by CAL FIRE. More intense fire, however, could pose a threat to individual clumps of

M. stoneana;

impacts to clumps of

M. stoneana

from intense fire events are discussed below under Factor E.

Summary of Factor A

We evaluated several factors with the potential to destroy, modify, or curtail

Monardella stoneana'

s habitat or range, including urban development, sand and gravel mining, type conversion due to frequent fire, and altered hydrology. Based on our review of the best available scientific and commercial information, we conclude that

M. stoneana

is not threatened by the present or threatened destruction, modification, or curtailment of its habitat or range, either now or in the foreseeable future.

B. Overutilization for Commercial, Recreational, Scientific, or Educational Purposes

To our knowledge, no commercial use exists for

Monardella stoneana.

The 1998 listing rule for

Monardella linoides

ssp.

viminea

suggested that professional and private botanical collecting could exacerbate the extirpation threat to the subspecies due to botanists favoring rare or declining species (63 FR 54938; October 13, 1998). However, we are not currently aware of any interest by botanists in collecting

M. stoneana.

Therefore, we do not believe that overutilization for commercial, recreational, scientific, or educational purposes constitutes a threat to this species, either now or in the foreseeable future.

C. Disease or Predation

Neither disease nor predation was known to be a threat affecting

Monardella linoides

ssp.

viminea

(63 FR 54938; October 13, 1998) at the time of listing. Data from the CNDDB (CNDDB 2010b) list grazing as a potential threat for the

M. stoneana

occurrence located on the Otay Ranch Preserve (EO 4). However, we have no other information quantifying the extent of this grazing and its impact on this occurrence. Therefore, based on the best available

scientific and commercial information, neither disease nor herbivory constitutes a threat to

M. stoneana,

either now or in the foreseeable future.

D. The Inadequacy of Existing Regulatory Mechanisms

At the time of listing, regulatory mechanisms identified as providing some level of protection for

Monardella linoides

ssp.

viminea

included: (1) The Act in cases where

M. linoides

ssp.

viminea

co-occurred with a Federally listed species; (2) California Endangered Species Act (CESA), as the species was listed as endangered in California in 1979; (3) the California Environmental Quality Act (CEQA); (4) implementation of conservation plans pursuant to California's Natural Community Conservation Planning Act; (5) local laws and regulations; and (6) enforcement of Mexican laws (63 FR 54938; October 13, 1998). The listing rule provided an analysis of the potential level of protection provided by these regulatory mechanisms (63 FR 54938; October 13, 1998). With the proposed separation of

M. viminea

from

M. stoneana,

we have re-evaluated current protective regulatory mechanisms for

M. stoneana,

as discussed below. However, as with

M. viminea,

protections afforded to

M. stoneana

under the Act as part of

M. linoides

ssp.

viminea,

the currently listed entity, would continue to apply only if we determine to retain listed status for

M. stoneana.

Therefore, for purposes of our analysis, we do not include the Act as an existing regulatory mechanism that protects

M. stoneana.

We do note that

M. stoneana

would likely continue to receive protection indirectly through habitat conservation plans approved under section 10 of the Act and Natural Community Conservation Plans (NCCPs) approved under the State of California that will cover

M. stoneana

even if the species is not Federally listed.

Federal Regulations

National Environmental Policy Act (NEPA)

All Federal agencies are required to adhere to the National Environmental Policy Act (NEPA) of 1970

for projects they fund, authorize, or carry out. The Council on Environmental Quality's regulations for implementing NEPA (40 CFR 1500-1518) state that in their environmental impact statements agencies shall include a discussion on the environmental impacts of the various project alternatives (including the proposed action), any adverse environmental effects which cannot be avoided, and any irreversible or irretrievable commitments of resources involved (40 CFR 1502). NEPA itself is a disclosure law that provides an opportunity for the public to submit comments on a particular project and propose other conservation measures that may directly benefit listed species; however, it does not impose substantive environmental mitigation obligations on Federal agencies. Any such measures are typically voluntary in nature and are not required by the statute. Activities on non-Federal lands are also subject to NEPA if there is a Federal nexus.

Wilderness Act and Federal Land Policy and Management Act

Monardella stoneana

is a BLM-designated sensitive species (BLM 2010, p. 8). BLM-designated sensitive species are those species requiring special management consideration to promote their conservation and reduce the likelihood and need for future listing under the Act. This status makes conservation of

M. stoneana

a management priority in the Otay Mountain Wilderness, in which approximately 34 percent of

M. stoneana

occurs.

The Federal Land Policy and Management Act of 1976 (FLPMA) (43 U.S.C. 1701

et seq.

) governs the management of public lands under the jurisdiction of the BLM. The legislative goals of FLPMA are to establish public land policy; to establish guidelines for its [BLM's] administration; and to provide for the management, protection, development, and enhancement of the public lands. While FLPMA generally directs that public lands be managed on the basis of multiple use, the statute also directs that such lands be managed to “protect the quality of scientific, scenic, historical, ecological, environmental, air and atmospheric, water resource, and archeological values; * * * [ to] preserve and protect certain public lands in their natural condition; [and to] * * * provide food and habitat for fish and wildlife * * * .” (43 U.S.C. 1701(a)(8)). Although the BLM has a multiple-use mandate under the FLPMA which allows for grazing, mining, and off-road vehicle use, the BLM also has the ability under the FLPMA to establish and implement special management areas such as Areas of Critical Environmental Concern, wilderness areas, research areas, and so forth. BLM's South Coast Resource Management Plan covers the San Diego County area.

The Otay Mountain Wilderness Act (1999) (Pub. L. 106-145) and BLM management policies provide protection for all

Monardella stoneana

occurring within the Otay Mountain Wilderness. The Otay Mountain Wilderness Act provides that the Otay Mountain designated wilderness area (

i.e.,

Otay Mountain Wilderness; 18,500 ac (7,486 ha)) will be managed in accordance with the provisions of the Wilderness Act of 1964 (16 U.S.C. 1131

et seq.

). The Wilderness Act of 1964 strictly limits the use of wilderness areas, imposing restrictions on vehicle use, new developments, chainsaws, mountain bikes, leasing, and mining, in order to protect the natural habitats of the areas, maintain species diversity, and enhance biological values. Lands acquired by BLM within the Otay Mountain Wilderness boundaries become part of the designated wilderness area and are managed in accordance with all provisions of the Wilderness Act and regulations pertaining to the Wilderness Act.

The Memorandum of Understanding (MOU) between the Service, the BLM, the County of San Diego, the City of San Diego, SANDAG, and the CDFG, was issued in 1994 in conjunction with the development of the County of San Diego Subarea Plan under the MSCP for cooperation in habitat conservation planning and management (BLM 1994, pp. 1-8), and applies to the Otay Mountain Wilderness because it falls entirely within the boundary of this subarea plan. The MOU (BLM 1994, p. 3) details BLM's commitment to manage lands to “conform with” the County of San Diego Subarea Plan, which in turn requires protection of

M. stoneana

(see Habitat Conservation Plans section below). Additionally, pursuant to the MOU, private lands acquired by BLM will be evaluated for inclusion within the designated wilderness area, and if the lands do not meet wilderness qualifications, these lands would be included in the MSCP conservation system (BLM 1994, p. 3). Therefore, protections provided by the County of San Diego Subarea Plan under the MSCP (see Habitat Conservation Plans section below) also apply to the Otay Mountain Wilderness.

Protections for

Monardella stoneana

are also included in the BLM's draft of the South Coast Resource Management Plan (SCRMP). Fire management activities occur on Otay Mountain as part of the BLM's current (1994) South Coast Resource Management Plan. In addition, at some point in the future on an as-needed basis, additional brush clearing and other fuels modifications, including burning, may occur.

The BLM is collaborating with the Service to revise the South Coast Resource Management Plan, which covers the Otay Mountain Wilderness.

The draft revised plan specifically includes a goal of restoring fire frequency to 50 years through fire prevention or suppression and prescribed burns; once an area has not burned for 50 years, the plan allows for annual prescribed burning of up to 500 ac (200 ha) in the Otay Mountain Wilderness (BLM 2010, pp. 4-171—4-172). We believe the management regime undertaken by BLM under the SCRMP is adequate to protect the species and its habitat from the threat of type conversion due to frequent fire (Factor A).

State and Local Regulations

Native Plant Protection Act (NPPA) and California Endangered Species Act (CESA)

Under provisions of NPPA (Division 2, chapter 10 section 1900

et seq.

of the CFG code) and CESA (Division 3, chapter 1.5, section 2050

et seq.

of the CFG code), the CDFG Commission listed

Monardella linoides

ssp.

viminea

as endangered in 1979. Currently, the State of California recognizes the State-listed entity as

M. viminea.

No such recognition is afforded

M. stoneana

under CESA. Though not listed under CESA, the CDFG does recognize

M. stoneana

as a rare and imperiled plant (lists S1.2 and 1B.2).

California Environmental Quality Act (CEQA)

The California Environmental Quality Act (CEQA) (Public Resources Code 21000-21177) and the CEQA Guidelines (California Code of Regulations, Title 14, Division 6, Chapter 3, Sections 15000-15387) requires State and local agencies to identify the significant environmental impacts of their actions and to avoid or mitigate those impacts, if feasible. CEQA applies to projects proposed to be undertaken or requiring approval by State and local government agencies, and the lead agency must complete the environmental review process required by CEQA, including conducting an Initial Study to identify the environmental impacts of the project and determine whether the identified impacts are significant; if significant impacts are determined, then an Environmental Impact Report must be prepared to provide State and local agencies and the general public with detailed information on the potentially significant environmental effects (California Environmental Resources Evaluation System, 2010). “Thresholds of Significance” are comprehensive criteria used to define environmentally significant impacts based on quantitative and qualitative standards and include impacts to biological resources such as candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the CDFG or the Service; or any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the CDFG or Service (CEQA Handbook, Appendix G, 2010). Defining these significance thresholds helps ensure a “rational basis for significance determinations” and provides support for the final determination and appropriate revisions or mitigation actions to a project in order to develop a mitigated negative declaration rather than an Environmental Impact Report (Governor's Office of Planning and Research, 1994, p. 5). Under CEQA, projects may move forward if there is a statement of overriding consideration. If significant effects are identified, the lead agency has the option of requiring mitigation through changes in the project or to decide that overriding considerations make mitigation infeasible (CEQA section 21002). Protection of listed species through CEQA is, therefore, dependent upon the discretion of the lead agency involved.

Otay Mountain Ecological Reserve

Fifty-five percent of

Monardella stoneana

occurrences are found on the Otay Mountain Ecological Reserve, which is owned by the State of California and managed by CDFG. The Reserve is managed in a manner consistent with protections applying to the Otay Mountain Wilderness Area (T. Nelson 2011, pers. comm.). In the case of Otay Mountain Ecological Reserve, those measures include protection from development, watershed alteration, and fire management. Fire management prevents stress on

M. stoneana

habitat due to type conversion caused by too frequent fires (Factor A).

The Natural Community Conservation Planning (NCCP) Act

The NCCP program is a cooperative effort between the State of California and numerous private and public partners with the goal of protecting habitats and species. An NCCP identifies and provides for the regional or area-wide protection of plants, animals, and their habitats, while allowing compatible and appropriate economic activity. The program began in 1991 under the State's NCCP Act (CFG Code 2800-2835). The primary objective of the NCCP program is to conserve natural communities at the ecosystem scale while accommodating compatible land uses (

http://www.dfg.ca.gov/habcon/nccp/

). Regional NCCPs provide protection to Federally listed species by conserving native habitats upon which the species depend. Many NCCPs are developed in conjunction with HCPs prepared pursuant to the Act. The City and County of San Diego Subarea Plans under the MSCP are discussed below under the discussion of the Act.

San Diego Multiple Species Conservation Plan (MSCP)

Monardella linoides ssp. viminea

is a covered species under the San Diego Multiple Species Conservation Program (MSCP) (City of San Diego 1997, Table 3-5). The most recent revision of the Rare Plant Monitoring Review lists

M. stoneana

as a covered species and recognized narrow endemic (McEachern

et al.

2007, p. 33). The MSCP is a regional conservation plan covering 582,000 acres in southwestern San Diego County and is designed to protect sensitive species and habitats within the boundaries of the plan. The MSCP covers 582,243 ac (235,625 ha) and 12 jurisdictions. Each jurisdiction is responsible for developing its own subarea plan to implement the regional MSCP within that jurisdiction.

Known occurrences of

Monardella stoneana

located within the City of San Diego Subarea Plan under the MSCP include the occurrence just east of Buschalaugh Cove on the lower Otay Reservoir (EO 5) and a portion of the occurrence in an unnamed tributary of Cottonwood Creek east of Marron Valley (EO 6). The City of San Diego MSCP Subarea Plan requires preservation of 100 percent of the occurrences on city-owned lands in the Otay area. City-owned lands represent a total of 7 percent of habitat for the species. Additional impact avoidance and other measures are required under the City's plan to protect narrow endemic species, such as

M. stoneana,

and the subarea plan includes area-specific management directives designed to maintain long-term survival in the planning area (Service 1997, pp. 104-105). Under the City of San Diego Subarea Plan, impacts to narrow endemic plants, including

M. stoneana,

inside the MHPA (Multi-Habitat Protection Area) will be avoided. Additionally, the City has completed a fire management plan for the Marron Valley area. This plan outlines as major goals the reduction of too-short fire return intervals. It also provides for protection of native plant community structure and biodiversity, including protection for

M. stoneana

and the canyon where it is found (EO 1) (Tierra Data 2006, pp. 4-1-4-2).

The County of San Diego Subarea Plan covers 252,132 ac (102,035 ha) in

the southwestern portion of the County's unincorporated lands, and is implemented in part by the Biological Mitigation Ordinance (BMO). As discussed in the Wilderness Act and Federal Land Policy and Management Act section above, protections provided by the County of San Diego Subarea Plan under the MSCP also apply to the Otay Mountain Wilderness, and thus are discussed here. The County of San Diego Subarea plan outlines the specific criteria and requirements for projects within the MSCP subarea plan's boundaries to alleviate threats from development and increased fire frequency (see MSCP, County of San Diego Subarea Plan (2007) and County of San Diego Biological Mitigation Ordinance (Ord. Nos. 8845, 9246) 1998). The BMO requires that all impacts to narrow endemic plant species, including

Monardella stoneana,

be avoided to the maximum extent practicable (City of San Diego 2007, p. 11). All projects within the County's MSCP subarea plan boundaries must comply with both the MSCP requirements and the County's policies under CEQA.

The private land on Otay Mountain where

Monardella stoneana

is known to occur is part of Otay Ranch; this land is zoned as “Open Space” by the County of San Diego and identified as part of the County of San Diego's preserve for the MSCP. Only 4 percent of

M. stoneana

habitat occurs on private land. This land is also covered by the Otay Ranch Phase 2 Resource Management Plan (Otay Ranch 2002), approved by the County in 2002. This plan provides for the phased conservation and development of lands in southern San Diego County. A large portion of land is identified for conservation and will be dedicated as associated development occurs. The Otay Ranch Phase 2 Management Plan provides protection for 100 percent of

M. stoneana

occurring on the preserve (Otay Ranch 2002, p. 144) and includes provisions to manage the 4 percent of

M. stoneana

habitat that is

on private land in a way that will benefit this species (Otay Ranch 2002, pp. 18-19, 52-53).

Additionally, the County of San Diego Resource Protection Ordinance (RPO) (County of San Diego 2007) applies to unincorporated lands in the County, both within and outside of the MSCP subarea plan boundaries. The RPO identifies restrictions on development to reduce or eliminate impacts to natural resources, including wetlands, wetland buffers, floodplains, steep slope lands, and sensitive habitat lands. Sensitive habitat lands are those that support unique vegetation communities or those that either are necessary to support a viable population of sensitive species (such as

M. stoneana

), are critical to the proper functioning of a balanced natural ecosystem, or serve as a functioning wildlife corridor (County of San Diego, 2007, p. 3). They can include areas that contain maritime succulent scrub, southern coastal bluff scrub, coastal and desert dunes, calcicolous scrub, and maritime chaparral, among others. Impacts to RPO sensitive habitat lands are only allowed when all feasible measures have been applied to reduce impacts and when mitigation provides an equal or greater benefit to the affected species (County of San Diego, 2007, p. 13).

Summary of Factor D

On City and County lands occupied by

Monardella stoneana

or containing its habitat, we believe the County of San Diego Resource Protection Ordinance, the Biological Mitigation Ordinance, and the Subarea plans for the City and County of San Diego provide mechanisms to conserve

M. stoneana

in association with new development or other proposed projects, and they provide mechanisms for the creation of biological reserves. The County of San Diego subarea plan provides protective mechanisms for the small percentage of

M. stoneana

on private land

for new development or other proposed projects, and includes provisions for monitoring and management through development of location-specific management plans. Unlike for habitat containing

M. viminea,

the City of San Diego has developed final monitoring and management plans for

M. stoneana.

Conservation measures addressing stressors from type conversion due to frequent fire are thus identified, and are being carried out at the Marron Valley occurrence, which is the only city-owned land where

M. stoneana

is extant. However, as only a small percentage of

M. stoneana

occurs on city-owned lands, these actions on their own, although providing a benefit to the one occurrence on city-owned land, are not enough to protect the species as a whole.

On land owned and managed by the CDFG and BLM, which contain approximately 88 percent of all occurrences of

Monardella stoneana,

fire management is provided by CAL FIRE, and further protection of natural resources on state lands is provided by management conducted consistent with the Wilderness Act.

Based on our review of the best available scientific and commercial information, we conclude

M. stoneana

is not threatened by inadequate existing regulatory mechanisms. Federal, State, and local regulatory mechanisms help to reduce wildfire impacts, primarily to property and human safety; they do not adequately protect

M. stoneana

from direct mortality caused by megafires. However, the impact of megafire on wildlands is not a threat that is susceptible to elimination by regulatory mechanisms. Therefore, we do not find existing regulations inadequate to protect

M. stoneana,

now or in the foreseeable future.

E. Other Natural or Manmade Factors Affecting Its Continued Existence

Trampling

Trampling was identified as a threat to

Monardella linoides

ssp.

viminea

in the original listing rule (63 FR 54938; October 13, 1998). Trampling by pedestrians may result in damage or death to

M. stoneana

plants. The City of San Diego MSCP previously identified Off-Highway Vehicle (OHV) activity and disturbance from illegal immigrant activity as a major management issue (City of San Diego 1997, p. 52). All

M. stoneana

clusters occur in close proximity to the Mexico border, where historically many illegal immigrants cross on foot. Monitoring reports previously noted immigrant trails through

M. stoneana

habitat at the Otay Lakes location (City of San Diego 2006, p. 8). However, the recent border fence construction and other enforcement activities in the Otay Mountain Wilderness area have reduced illegal immigrant traffic (Ford 2010, p. 1), and thus potential impacts of trampling at the Otay Lakes, Marron Valley, and Otay Mountain locations. So while there may be some impacts due to trampling to individual plants, it is unlikely to occur at levels that would affect the status of the species. Based on the best scientific information, we believe that trampling (human disturbance activities) does not pose a significant risk to the persistence of

M. stoneana

now or in the foreseeable future.

Nonnative Plant Species

The listing rule identifies nonnative plants as a threat to

Monardella linoides

ssp.

viminea

(63 FR 54938; October 13, 1998). San Diego County habitats have been altered by invasion of nonnative species (Soule

et al.

1992, p. 43). Nonnative grasses, which frequently grow more quickly than native species, can smother seedling and mature

M. viminea

and prevent natural growth (Rebman and Dossey 2006a, p. 12). The same effect is likely for

M. stoneana.

Monitors for the City of San Diego MSCP recorded invasive plants at the Marron Valley location in the 2008 and

2009 survey reports (City of San Diego 2008, p. 2; City of San Diego 2009, p. 1). At the Otay Lakes location, the invasive plant tamarisk was documented in 2006 (City of San Diego 2006, p. 8), and nonnative grasses were documented in 2008 and 2009 (City of San Diego 2008, p. 2; City of San Diego 2009, p. 2).

However, despite the presence of nonnative plants in the range of

Monardella stoneana,

monitoring reports have not recorded the same level of invasion by nonnative grasses that has occurred in the vicinity of

M. viminea.

As discussed under Factor A, the percent ground cover of nonnative and native plant species has increased between 2008 and 2010 at both Otay Lakes and Marron Valley. Additionally, the number of individual plants of

M. stoneana

at Marron Valley has not changed since 2006 (City of San Diego 2006, p. 1; City of San Diego 2008, p. 1; City of San Diego 2009, p. 1; City of San Diego 2010, p. 11). These observations are consistent with the observation of Minnich and Bahre (1995, p. 17) that generally, the ground cover of all herbaceous plants, including that of nonnative grasses, was absent or consisted of thinly scattered plants within the chaparral along the California-Baja California boundary. Furthermore, these monitored occurrences have not undergone the same increase in nonnative vegetation recorded at

M. viminea

occurrences in Sycamore Canyon and on MCAS Miramar. Therefore, based on the best available scientific information, we find that nonnative species do not constitute a threat to the continued existence of

M. stoneana.

Small Population Size

The original listing rule identified the restricted range and small population size of

Monardella linoides

ssp.

viminea

as a threat as it increases the possibility of extinction due to chance events such as floods, fires, or drought, outside the natural variability of the ecosystem (63 FR 54938; October 13, 1998; Lande 1993, p. 912). With the split of

M. linoides

ssp.

viminea

into two entities, the magnitude of this threat would likely increase; however, we note that several additional

M. stoneana

occurrences have been discovered. Similarly, Prince (2009, p. 2) suggests that multiple undiscovered occurrences of

M. stoneana

may exist in the vicinity of Tecate Peak. This area has not been extensively surveyed, as it is difficult to access. Additional habitat may exist in Mexico; however, we are unaware of any surveys confirming the presence or absence of

M. stoneana

in Mexico, apart from plants seen directly across the border. Based on information in our files, these are the only occurrences in Mexico of which we are aware. However, suitable habitat and landscape conditions exist in Mexico, close to the current range of the species in the United States.

Of the 20 known occurrences of

Monardella linoides

ssp.

viminea

at the time of listing, only 2 were later considered to be

M. stoneana.

Subsequent surveys have identified additional occurrences, and

M. stoneana

is currently known from approximately eight occurrences in the Otay Mountains area (CNDDB 2010b). The number of plants in Mexico is unknown and has been minimally investigated. Plants across the border in Mexico are visible from at least two occurrences south of Otay Mountain, but these occurrences have not been formally surveyed. Additionally, the most recent survey for this area was in 2005 (CNDDB 2010a), so the continued existence of these Mexico occurrences and the number of clumps present cannot be confirmed.

Any decrease in occurrences may result in decreased reproductive opportunities and genetic exchange between canyons through pollination. However, effects from this threat may be less severe if more occurrences exist in Mexico than are currently known. However, we do not consider small population size alone sufficient to meet the information threshold indicating that the species warrants listing. In the absence of information identifying threats to the species and linking those threats to the rarity of the species, the Service does not consider rarity or small populations alone to be a threat. For example, the habitat supporting

M. viminea

faces significant threats from the impacts of fire, altered hydrologic regimes, and competition with nonnative plants. As discussed above,

M. stoneana

does not face such threats. A species that has always had small population sizes or been rare, yet continues to survive, is likely well equipped to continue to exist into the future. Many naturally rare species have persisted for long periods within small geographic areas, and many naturally rare species exhibit traits that allow them to persist despite their small population sizes.

Monardella stoneana

appears to have persisted for over two decades in the two occurrences known since the 1970s and 1980s, respectively (CNDDB 2010b; EOs 1 and 4); this is in contrast to

M. viminea

occurrences, many of which have undergone population declines during the same time period. The other seven occurrences were discovered in 2003 or later, so long-term data are not available; one of those seven occurrences has since been extirpated (EO 5).

Monardella stoneana

has not experienced a significant population decline since listing, nor have multiple occurrences been extirpated. One of two occurrences monitored by the City of San Diego (EO 1) has remained stable throughout the past decade of monitoring, though one occurrence (EO 5) containing one clump was extirpated (although the EO 5 occurrence contained a maximum of only two clumps since monitoring began in 2000). This is in contrast to

M. viminea,

which has experienced a loss of several populations since listing. Consequently, the fact that this species is rare and has small populations does not indicate that it is in danger of extinction now or in the foreseeable future. Therefore, though small population size may pose a threat to

M. stoneana,

it is not alone enough to cause the extinction of the species within the foreseeable future.

Fire

As discussed under Factor E for

Monardella viminea,

fire can impact individual plants. This is especially true of megafire events that cannot be controlled or ameliorated through management efforts. A narrow endemic such as

M. stoneana

could be especially sensitive to megafire events. One large fire could impact all or a large proportion of the entire area where the species is found, as occurred for

M. viminea

in the 2003 Cedar fire. However, as discussed in Factor E for

M. viminea,

the decline of the burned occurrences of

M. viminea

was not as severe as initially expected. We expect that

M. stoneana

would experience the same ability to sprout from the roots, as it is closely related to

M. viminea.

Furthermore, despite the increased frequency of fire,

M. stoneana

has persisted through all large fires in the region. The GIS fire boundaries show that each occurrence of

M. stoneana

has been burned at least once in the past decade. In the past two decades, 8 of 9 EOs burned two or more times, and 4 occurrences burned three or more times. The only reports of damage are from EO 5, which lost its one remaining plant, and EO 4, which was “damaged” in a recent (unspecified) fire, but not extirpated (CNDDB 2010b). In the occasion that a fire impacts all of the occurrences, we anticipate that the effects to

M. stoneana

individuals would be comparable to

M. viminea,

where the best available information show individuals are recovering from having 98 percent of the occurrences on MCAS Miramar being burned in the 2003 Cedar Fire.

Monardella stoneana.

However, given the species' persistence through past fires, and the ability of a closely related species to recover from direct impact by fires, we do not expect that megafire is a significant threat to individual

M. stoneana

plants now, nor is likely to become a threat in the foreseeable future.

Climate Change

As noted above in our status determination for

Monardella viminea,

a broad consensus exists among scientists that the earth is in a warming trend caused by anthropogenic greenhouse gases such as carbon dioxide (IPCC 2007). Researchers have documented climate-related changes in California (Croke

et al.

1998, pp. 2128, 2130; Breshears

et al.

2005, p. 15144). Predictions for California indicate prolonged drought and other climate-related changes will continue in the future (

e.g.,

Field

et al.

1999, pp. 8-10; Lenihen

et al.

2003, p. 1667; Hayhoe

et al.

2004, p. 12422; Breshears

et al.

2005, p. 15144; Seager

et al.

2007, p. 1181; IPCC 2007, p. 9). Models are not yet powerful enough to predict what will happen in localized regions such as southern California and northern Baja California, but many scientists believe warmer, wetter winters and warmer, drier summers will occur within the next century (Field

et al.

1999, pp. 2-3, 20). The impacts on species like

M. stoneana,

which depend on specific hydrological regimes, may be more severe (Graham 1997, p. 2).

Monardella stoneana

occurrences (Lake Cuyamaca, San Diego County, California), 8 of 10 years had precipitation significantly below normal (San Diego County Water Authority 2010, p. 2). This extended drought has cumulatively affected moisture regimes, riparian habitat, and vegetative conditions in and around suitable habitat for

M. stoneana,

increasing the stress on individual plants. As stated above, future climate changes may lead to similar, if not more severe, conditions.

The predicted drought could impact the dynamics of the streambeds where

Monardella stoneana

grows. Soil moisture and transportation of sediments by downstream flow have been identified as key habitat features required by

M. stoneana.

Monardella

While drier conditions associated with climate change may result in increased fire frequency within some plant communities as discussed under Factor A, the effect of more arid conditions is not known on chaparral, the plant community associated with

Monardella stoneana.

According to Minnich and Bahre (1997, p. 20), fires in the chaparral of northern Baja California, Mexico, are smaller and more frequent than those observed across the border in southern California. Nonetheless, despite these differences in the present fire regimes within chaparral in California and Mexico, Minnich and Bahre (1997, p. 20) concluded that their “repeat photographs of the monument markers, field samples, repeat aerial photography, and fire history maps show that chaparral succession is similar across the international boundary between Jacumba [in California] and Tecate [in Mexico] and that chaparral succession along the border is similar to that found elsewhere in California.” Except for a statistically significant correlation that early autumn rains cut short the fire season at its peak, Keeley and Fotheringham (2003, p. 235) did not find patterns between rainfall and burning for chaparral and coastal sage shrublands. As a result, increased aridity may have little effect on chaparral.

Preliminary information for

Monardella stoneana

does show that the effects of climate change on chaparral may be less than the effects on coastal sage scrub (see Climate Change section for

M. viminea

above). While we recognize that climate change and increased drought associated with climate change are important issues with potential effects to listed species and their habitats, the best available scientific evidence does not give specific evidence for us to formulate accurate predictions regarding climate change's effects to particular species, including

M. stoneana,

at this time. Therefore, we do not consider global climate change a current threat to

M. stoneana,

either now or in the foreseeable future.

Summary of Factor E

We found no evidence that other natural or manmade factors pose a significant threat to

M. stoneana.

Based on a review of the best available scientific and commercial data, trampling and nonnative invasive plant species are not a significant threat. We conclude based on the best available scientific information that

M. stoneana

could be affected temporarily by fire impacts associated with the death of individual plants; however, we do not consider this a threat to the continued existence of the species. Small population size could exacerbate other threats, but as there are none, this is not a factor; small population size in itself does not cause

M. stoneana

to be warranted for listing. In addition, BLM conducts ongoing management that provides a benefit to

M. stoneana.

Finally, with regard to the direct and indirect effects of climate change on individual

M. stoneana

plants, we have no information at this point to demonstrate that predicted climate changes pose a significant threat to the species now or in the foreseeable future.

Proposed Determination—

Monardella stoneana

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to

Monardella stoneana.

Unlike

M. viminea, M. stoneana

has not undergone a dramatic decline in population size. While megafire and small population size may impact

M. stoneana,

these factors do not pose a threat to the continued existence of the species. Apart from those factors, we found no significant threats to

M. stoneana

related to Factors A, B, C, D, or E, as described above. We find that the best available information for Factor A (The Present or Threatened Destruction, Modification, or Curtailment of Its Habitat or Range), including information on the potential effects of urban development, sand and gravel mining, type conversion due to frequent fire, and altered hydrology, indicates that listing

M. stoneana

as endangered or threatened under the Act is not warranted based on the present or threatened destruction, modification, or curtailment of its habitat or range. To the extent that

M. stoneana

may be experiencing localized impacts, analysis of recent and current surveys of

M. stoneana

habitat in the Otay Mountain locations indicate that its habitat is

under protective status and remains in relatively good condition, with active management and monitoring activities. We found no available information concerning Factors B (Overutilization) and C (Disease or Predation) to indicate that listing

M. stoneana

as endangered or threatened under the Act is warranted. We find that the best available information concerning Factor D (Inadequacy of Existing Regulatory Mechanisms) indicates that listing the

M. stoneana

as endangered or threatened under the Act is not warranted based on inadequacy of existing regulations. We find that the best available information concerning Factor E (Other Natural or Manmade Factors Affecting Its Continued Existence) indicates that trampling and nonnative plants are not currently threats to the continued existence of

M. stoneana,

nor are they expected to be in the foreseeable future. We do not consider

M. stoneana'

s small population size in and of itself a threat such that the species warrants listing, nor is it expected to be in the foreseeable future. A species like

M. stoneana

that has always had small population sizes or been rare, yet continues to survive, is likely well equipped to continue to exist into the future. Additionally, unlike

M. viminea, M. stoneana

has not undergone a dramatic decline in population size. We have no information to demonstrate that predicted climate changes will result in a significant threat to the species now or in the foreseeable future. Even though

M. stoneana

could be affected by megafire, we do not believe that megafire poses a significant threat to the existence of the species now or in the foreseeable future.

In conclusion, we have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats faced by

Monardella stoneana.

Our review of the information pertaining to the five threat factors does not support a conclusion that threats of sufficient imminence, intensity, or magnitude exist—either singly or in combination—to the extent that the species is in danger of extinction, or likely to become so within the foreseeable future, throughout all or a significant portion of its range. Therefore, based on the best available scientific information, we find

M. stoneana

does not warrant listing at this time. However, if we receive new information that alters our analysis, we will revisit and re-evaluate the status of

M. stoneana.

We are specifically seeking public comment on this determination. Please refer to the

ADDRESSES

section of this rule for information on where to submit your comments and materials concerning this proposed rule.

Critical Habitat—

Monardella viminea

Due to the taxonomic split of

Monardella linoides

ssp.

viminea

into two distinct taxa (

Monardella viminea

(willowy monardella) and

Monardella stoneana

(Jennifer's monardella); see

Taxonomic and Nomenclatural Changes Affecting

Monardella linoides

ssp.

viminea section above), and our conclusions that

M. viminea

is endangered and

M. stoneana

is not warranted for listing, we are proposing revising critical habitat for

M. viminea.

If we subsequently determine based on the best available information that

M. stoneana

should be listed, we will propose critical habitat, if prudent, for

M. stoneana.

Background

Critical habitat is defined in section 3 of the Act as:

(1) The specific areas within the geographical area occupied by the species, at the time it is listed in accordance with the Act, on which are found those physical or biological features:

(a) Essential to the conservation of the species and

(b) That may require special management considerations or protection; and

(2) Specific areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species.

Conservation, as defined under section 3 of the Act, means to use and the use of all methods and procedures that are necessary to bring an endangered or threatened species to the point at which the measures provided pursuant to the Act are no longer necessary. Such methods and procedures include, but are not limited to, all activities associated with scientific resources management such as research, census, law enforcement, habitat acquisition and maintenance, propagation, live trapping, and transplantation, and, in the extraordinary case where population pressures within a given ecosystem cannot be otherwise relieved, may include regulated taking.

Critical habitat receives protection under section 7 of the Act through the requirement that Federal agencies insure, in consultation with the Service, that any action they authorize, fund, or carry out is not likely to result in the destruction or adverse modification of critical habitat. The designation of critical habitat does not affect land ownership or establish a refuge, wilderness, reserve, preserve, or other conservation area. Such designation does not allow the government or public to access private lands. Such designation does not require implementation of restoration, recovery, or enhancement measures by non-Federal landowners. Where a landowner seeks or requests Federal agency funding or authorization for an action that may affect a listed species or critical habitat, the consultation requirements of section 7(a)(2) would apply, but even in the event of a destruction or adverse modification finding, the obligation of the Federal action agency and the landowner is not to restore or recover the species, but to implement reasonable and prudent alternatives to avoid destruction or adverse modification of critical habitat.

For inclusion in a critical habitat designation, the habitat within the geographical area occupied by the species at the time it was listed must contain physical and biological features which are essential to the conservation of the species and which may require special management considerations or protection. Critical habitat designations identify, to the extent known using the best scientific and commercial data available, those physical and biological features that are essential to the conservation of the species (such as space, food, cover, and protected habitat), focusing on the principal biological or physical constituent elements (primary constituent elements) within an area that are essential to the conservation of the species (such as roost sites, nesting grounds, seasonal wetlands, water quality, tide, soil type). Primary constituent elements are the elements of physical and biological features that are essential to the conservation of the species.

Under the Act, we can designate critical habitat in areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species. We designate critical habitat in areas outside the geographical area occupied by a species only when a designation limited to its range would be inadequate to ensure the conservation of the species. When the best available scientific data do not demonstrate that the conservation needs of the species require such additional areas, we will not designate critical habitat in areas outside the geographical area occupied by the species at the time of listing. An area currently occupied by

the species, but that was not occupied at the time of listing may, however, be essential to the conservation of the species and may be included in the critical habitat designation.

Section 4 of the Act requires that we designate critical habitat on the basis of the best scientific and commercial data available. Further, our Policy on Information Standards Under the Endangered Species Act (published in the

Federal Register

on July 1, 1994 (59 FR 34271)), the Information Quality Act (section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), and our associated Information Quality Guidelines, provide criteria, establish procedures, and provide guidance to ensure our decisions are based on the best scientific data available. They require our biologists, to the extent consistent with the Act and with the use of the best scientific data available, to use primary and original sources of information as the basis for recommendations to designate critical habitat.

When we are determining which areas should be designated as critical habitat, our primary source of information is generally the information developed during the listing process for the species. Additional information sources may include the recovery plan for the species, articles in peer-reviewed journals, conservation plans developed by States and counties, scientific status surveys and studies, biological assessments, the species' most recent 5-year Review, or other unpublished materials and expert opinion or personal knowledge.

Habitat is dynamic, and species may move from one area to another over time. Climate change will be a particular challenge for biodiversity because the interaction of additional stressors associated with climate change and current stressors may push species beyond their ability to survive (Lovejoy 2005, pp. 325-326). The information currently available on the effects of global climate change and increasing temperatures does not make sufficiently precise estimates of the location and magnitude of the effects to enable us to accurately predict its impacts on the narrow habitat range of

Monardella viminea,

which is limited to the western portion of central San Diego County. We are also not currently aware of any climate change information specific to the habitat of

M. viminea

that would indicate what areas may become important to the species in the future. Therefore, we are unable to determine what additional areas, if any, may be appropriate to include in the critical habitat for this species to address the effects of climate change.

We recognize that critical habitat designated at a particular point in time may not include all of the habitat areas that we may later determine are necessary for the recovery of the species. For these reasons, a critical habitat designation does not signal that habitat outside the designated area is unimportant or may not be required for recovery of the species. Areas that are important to the conservation of the species, both inside and outside the critical habitat designation, will continue to be subject to: (1) Conservation actions implemented under section 7(a)(1) of the Act, (2) regulatory protections afforded by the requirement in section 7(a)(2) of the Act for Federal agencies to insure their actions are not likely to jeopardize the continued existence of any endangered or threatened species, and (3) the prohibitions of section 9 of the Act if actions occurring in these areas may affect the species. Federally funded or permitted projects affecting listed species outside their designated critical habitat areas may still result in jeopardy findings in some cases. These protections and conservation tools will continue to contribute to recovery of this species. Similarly, critical habitat designations made on the basis of the best available information at the time of designation will not control the direction and substance of future recovery plans, habitat conservation plans (HCPs), or other species conservation planning efforts if new information available at the time of these planning efforts calls for a different outcome.

Proposed Critical Habitat Designation for

Monardella viminea

Physical and Biological Features

In accordance with sections 3(5)(A)(i) and 4(b)(1)(A) of the Act and regulations at 50 CFR 424.12, in determining which areas within the geographical area occupied at the time of listing to designate as critical habitat, we consider the physical and biological features essential to the conservation of the species which may require special management considerations or protection. These include, but are not limited to:

(1) Space for individual and population growth and for normal behavior;

(2) Food, water, air, light, minerals, or other nutritional or physiological requirements;

(3) Cover or shelter;

(4) Sites for breeding, reproduction, or rearing (or development) of offspring; and

(5) Habitats that are protected from disturbance or are representative of the historical, geographical, and ecological distributions of a species.

We derive the specific physical and biological features required for

Monardella viminea

from studies of this species' habitat, ecology, and life history as described below. We also reviewed monitoring reports from private firms, the City of San Diego, Friends of Los Peñasquitos Canyon, the Service, and MCAS Miramar; technical reports; the CNDDB (CNDDB 2010a, EOs 1-31.); Geographic Information System (GIS) data (such as species occurrence data, soil data, land use, topography, aerial imagery, and ownership maps); correspondence to the Service from recognized experts; and other information as available. Additional information can be found in the final listing rule published in the

Federal Register

on October 13, 1998 (63 FR 54938).

The primary constituent elements required for

Monardella viminea

are derived from the physical and biological needs of this species as described in the Background section for

M. viminea

in the beginning of this proposal, the previous critical habitat rule (71 FR 65662; November 8, 2006), the final listing rule (63 FR 54938; October 13, 1998), and below. The areas in this proposed critical habitat contain or support the soil types, potential insect pollinators, and vegetation associated with

M. viminea

occupancy, and include areas adjacent to plants (or plant clumps) necessary to maintain associated physical processes, such as suitable hydrological regime, and biotic associations, such as pollination. These areas provide suitable space, water, minerals, and other physiological needs for reproduction and growth of

M. viminea.

We have determined that

M. viminea

requires the physical and biological features described below:

Space for Individual and Population Growth and for Normal Behavior

Habitats that provide space for growth and persistence of

Monardella viminea

include: (1) Washes in coastal sage scrub or riparian scrub vegetation; (2) terraced secondary benches, channel banks, and stabilized sand bars; (3) soils with a high content of coarse-grained sand and low content of silt and clay; and (4) open ground cover, less than half of which is herbaceous vegetation cover (Scheid 1985, pp. 30-35; Service 1998, p. 54938; Elvin and Sanders 2003,

pp. 426, 430; Kelly and Burrascano 2006, p. 51).

Food, Water, Air, Light, Minerals, or Other Nutritional or Physiological Requirements

Monardella viminea

is most often found on the first above-water sandbar in intermittent streambeds, where water runs for 24 to 48 hours after heavy rain events (Elvin and Sanders 2003, p. 430; Kelly and Burrascano 2006, p. 51). It can also be found within the streambed if flow is infrequent enough and the soil is stable (Scheid 1985, pp. 3, 38-39). The most robust

M. viminea

individuals tend to occur in wide, open canyons with broad channels and secondary benches, as opposed to narrow, graded canyons (Kassebaum 2010, pers. comm.).

Monardella viminea

plants are found on soil where subsurface layers stay relatively

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