# Endangered and Threatened Wildlife and Plants; Proposed Designation of Critical Habitat for the Arroyo Toad (Bufo californicus)

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URL: https://www.frixlaw.com/law-library/documents/fr%3A04-9204

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** April 28, 2004
- **Citation:** 69 FR 23254

## Text

DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN 1018-AT42

Endangered and Threatened Wildlife and Plants; Proposed Designation of Critical Habitat for the Arroyo Toad
(Bufo californicus)

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Proposed rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), propose to designate critical habitat for the federally endangered arroyo toad (
Bufo californicus
) pursuant to the Endangered Species Act of 1973, as amended (Act). We propose to designate a total of approximately 138,713 acres (ac) (56,133 hectares (ha)) of critical habitat in Monterey, Santa Barbara, Ventura, Los Angeles, San Bernardino, Riverside, Orange, and San Diego Counties, California.

We hereby solicit data and comments from the public on all aspects of this proposal, including data on economic and other impacts of designation. We may revise this proposal prior to final designation to incorporate or address new information received during the two public comment periods.

DATES:

We will accept comments from all interested parties until May 28, 2004. We must receive requests for public hearings, in writing, at the address shown in the
ADDRESSES
section by May 13, 2004.

ADDRESSES:

If you wish to comment, you may submit your comments and materials concerning this proposal by any one of these methods:

1. You may submit written comments and information to Diane Noda, Field Supervisor, U.S. Fish and Wildlife Service, Ventura Fish and Wildlife Office, 2493 Portola Road, Suite B, Ventura, CA 93003.

2. You may hand-deliver written comments to our Ventura Office, at the address given above.

3. You may submit comments by fax to our Ventura Office (facsimile 805/644-3958) or our Carlsbad Office (facsimile 760/431-9624).

4. You may send comments by electronic mail (e-mail) to:
fw1artoch@r1.fws.gov.
Please see the Public Comments Solicited section below for file format and other information about electronic filing. In the event that our internet connection is not functional, please submit your comments by the alternate methods mentioned above.

Comments and materials received, as well as supporting documentation used in the preparation of this proposed rule, will be available for public inspection, by appointment, during normal business hours at the Ventura Fish and Wildlife Office at the address given above, or at the Carlsbad Fish and Wildlife Office, 6010 Hidden Valley Road, Carlsbad, CA (telephone 760/431-9440).

FOR FURTHER INFORMATION CONTACT:

For information about Monterey, San Luis Obispo, Santa Barbara, and Ventura Counties, northern Los Angeles County, and the desert portion of San Bernardino County, contact Diane Noda, Field Supervisor, Ventura Fish and Wildlife Office, at the address given above (telephone 805/644-1766; facsimile 805/644-3958). For information about Los Angeles, San Bernardino, Riverside, Orange, and San Diego Counties, contact Jim Bartel, Field Supervisor, Carlsbad Fish and Wildlife Office, at the address given above (telephone 760/431-9440; facsimile 760/431-9624).

SUPPLEMENTARY INFORMATION:

Designation of Critical Habitat Provides Little Additional Protection to Species

In 30 years of implementing the Endangered Species Act of 1973, as amended (Act) (16 U.S.C. 1531
et seq.
), we have found that the designation of statutory critical habitat provides little additional protection to most listed species, while consuming significant amounts of available conservation resources. Our present system for designating critical habitat has evolved since its original statutory prescription into a process that provides little real conservation benefit, is driven by litigation and the courts rather than biology, limits our ability to fully evaluate the science involved, consumes enormous agency resources, and imposes huge social and economic costs. We believe that additional agency discretion would allow our focus to return to those actions that provide the greatest benefit to the species most in need of protection.

Role of Critical Habitat in Actual Practice of Administering and Implementing the Act

While attention to, and protection of, habitat is paramount to successful conservation actions, we have consistently found that, in most circumstances, the designation of critical habitat is of little additional value for most listed species, yet it consumes large amounts of conservation resources. Sidle (1987) stated, “Because the ESA can protect species with and without critical habitat designation, critical habitat designation may be redundant to the other consultation requirements of section 7.”

Currently, only 445 species or 36 percent of the 1,244 listed species in the U.S. under our jurisdiction have designated critical habitat. We address the habitat needs of all 1,244 listed species through conservation mechanisms such as listing, section 7 consultations, the section 4 recovery planning process, the section 9 protective prohibitions of unauthorized take, section 6 funding to the States, and the section 10 incidental take permit process. We believe that it is these measures that may make the difference between extinction and survival for many species.

Procedural and Resource Difficulties in Designating Critical Habitat

We have been inundated with lawsuits for our failure to designate critical habitat, and we face a growing number of lawsuits challenging critical habitat determinations once they are made. These lawsuits have subjected us to an ever-increasing series of court orders and court-approved settlement agreements, compliance with which now consumes nearly the entire listing program budget. This leaves us with little ability to prioritize our activities to direct scarce listing resources to the listing program actions with the most biologically urgent species conservation needs.

The consequence of the critical habitat litigation activity is that limited listing funds are used to defend active lawsuits, and to comply with the growing number of adverse court orders. As a result, our own proposals to list critically imperiled species, and make final listing determinations on existing proposals, are all significantly delayed.

The accelerated schedules of court-ordered designations have left us with almost no ability to provide for adequate public participation or to ensure a defect-free rulemaking process before making decisions on listing and critical habitat proposals due to the risks associated with noncompliance with judicially-imposed deadlines. This, in turn, fosters a second round of litigation in which those who fear adverse impacts from critical habitat designations challenge those designations. The cycle of litigation appears endless, is very expensive, and in the final analysis, provides relatively little additional protection to listed species.

The costs resulting from the designation include legal costs, the cost of preparation and publication of the designation, the analysis of the economic effects, and the cost of requesting and responding to public comment, and in some cases the costs of compliance with the National Environmental Policy Act of 1969—all are part of the cost of critical habitat designation. These costs result in minimal benefit to the species that is not already afforded by the protections of the Act enumerated earlier, and they directly reduce the funds available for direct and tangible conservation actions.

Public Comments Solicited

We intend that any final action resulting from this proposal will be as accurate and as effective as possible. Therefore, comments or suggestions from the public, other concerned governmental agencies, the scientific community, industry, or any other interested party concerning this proposed rule are hereby solicited. Comments particularly are sought concerning:

(1) The reasons why any habitat should or should not be determined to be critical habitat as provided by section 4 of the Act, including whether the benefit of designation will outweigh any threats to the species due to designation;

(2) Specific information on the amount and distribution of arroyo toad habitat, and what habitat is essential to the conservation of the species and why;

(3) Land use designations and current or planned activities in the areas proposed as critical habitat and their possible impacts on proposed critical habitat;

(4) Any foreseeable economic or other potential impacts resulting from the proposed designation—in particular, any impacts on small entities;

(5) Economic and other values associated with designating critical habitat for the arroyo toad, such as those derived from nonconsumptive uses (
e.g.
, hiking, camping, bird-watching, enhanced watershed protection, improved air quality, increased soil retention, “existence values,” and reductions in administrative costs); and

(6) Whether our approach to designating critical habitat could be improved or modified in any way to provide for greater public participation and understanding, or to assist us in accommodating public concerns and comments.

If you wish to comment, you may submit your comments and materials concerning this proposal by any one of several methods (see
ADDRESSES
section). Please submit Internet comments to
fw1artoch@r1.fws.gov
in ASCII file format and avoid the use of special characters or any form of encryption. Please also include “Attn: Arroyo toad” in your e-mail subject header and your name and return address in the body of your message. If you do not receive a confirmation from the system that we have received your Internet message, contact us directly by calling our Ventura Fish and Wildlife Office at phone number 805/644-1766. Please note that the Internet address
fw1artoch@r1.fws.gov
will be closed out at the termination of the public comment period.

Our practice is to make comments, including names and home addresses of respondents, available for public review during regular business hours. Individual respondents may request that we withhold their home address from the rulemaking record, which we will honor to the extent allowable by law. There also may be circumstances in which we would withhold from the rulemaking record a respondent's identity, as allowable by law. If you wish us to withhold your name and/or address, you must state this prominently at the beginning of your comment. However, we will not consider anonymous comments. We will make all submissions from organizations or businesses, and from individuals identifying themselves as representatives or officials of organizations or businesses, available for public inspection in their entirety. Comments and materials received will be available for public inspection, by appointment, during normal business hours at the above address.

Public Hearings

The Act provides for one or more public hearings on this proposal, if requested. Requests for public hearings must be made, in writing, at least 15 days prior to the close of the public comment period. We will schedule public hearings on this proposal, if any are requested, and announce the dates, times, and places of those hearings in the
Federal Register
and local newspapers at least 15 days prior to the first hearing.

Background

Background information on the arroyo toad can be found in our final designation of critical habitat for this species, published on February 7, 2001 (66 FR 9414). That information is incorporated by reference into this proposed rule. The following new information has come to our attention since that time:

(1) Individual toads have been observed as far as 1.2 miles (mi) (2 kilometers (km)) from the streams where they breed (Service 1999; Varanus Biological Services, Inc., in litt. 1999), but are most commonly found within 650 to 3,280 feet (ft) (200 to 1,000 meters (m)) of those streams in coastal areas with broad floodplains (Griffin
et al.
1999; Holland and Sisk 2000), and 160 to 650 ft (50 to 200 m) in more mountainous areas away from the coast (Ramirez 2002a, 2002b, 2002c, 2003). Arroyo toads typically burrow underground during periods of inactivity and thus tend to use upland habitats that have sandy, friable (readily crumbled) soils, but upland sites with extremely compact soils can also be used (D. Holland, in litt. 2000).

(2) Juvenile arroyo toads remain on or near the saturated substrate at the edges of breeding pools from a week to several months after metamorphosis (D. Holland, in litt. 2000). They are active during the day and can be exposed on the barren sand, although they are rather cryptic (
i.e.
, hidden or camouflaged) at this time. Crushing of toads by humans, livestock, or vehicles can be a substantial source of mortality at this stage (Service 1999; D. Holland, in litt. 2000).

(3) In a study using pitfall traps, Holland and Sisk (2000) reported arroyo toad captures in upland habitats averaging more than 1,640 ft (500 m) and 980 ft (300 m) from two separate coastal streams; one arroyo toad was even captured 3,940 ft (1,175 m) beyond the edge of the riparian habitat bordering the stream. However, radio telemetry and pitfall trap studies from a variety of inland streams often bordered by steep, dry terrain show arroyo toad activity typically closer to the active stream channel. Four separate studies of inland populations by Ramirez (2002a, 2002b, 2002c, 2003) showed that arroyo toads burrowed no farther than 121 to 1,062 ft (37 to 324 m) from the edge of a stream, with an overall average of approximately 52 ft (16 m) between a toad's burrow and the edge of the stream.

(4) The nonnative organisms whose introduction and spread into arroyo toad habitat can pose a particularly serious threat include, among others, giant reed (
Arundo donax
), bullfrogs (
Rana catesbeiana
), green sunfish (
Lepomis cyanellus
), and chytrid fungus (
Batrachochytrium dendrobatidis
) (Sweet 1992; Service 1999; S. Sweet, pers. comm. 2003).

(5) In addition to a variety of other human activities outlined in a previous
Federal Register
notice (66 FR 9414), off-highway vehicle use within stream channels, floodplains, and adjacent uplands and the inadvertent or intentional introduction of nonnative species may cause adverse impacts to arroyo toads.

Previous Federal Actions

We designated a total of approximately 182,360 acres (ac) (73,780 hectares (ha)) of critical habitat for the arroyo toad on February 7, 2001 (66 FR 9414). On November 6, 2001, the Building Industry Legal Defense Foundation, Foothill/Eastern Transportation Corridor Agency, National Association of Home Builders, California Building Industry Association, and Building Industry Association of San Diego County filed a lawsuit in the District of Columbia against the Service challenging the designation of arroyo toad critical habitat and alleging errors by the Service in promulgating the final rule.
Building Industry Legal Defense Foundation, et al.
v.
Gale Norton, Secretary of the Interior, et al.
Civ. No. 01-2311 (JDB) (D.D.C.). On October 30, 2002, the court set aside the designation and ordered us to publish a new critical habitat designation final rule for the arroyo toad by July 30, 2004.

This proposal for critical habitat differs from the previous designation of critical habitat for the arroyo toad with respect to the mapping grid size and changes in locations of critical habitat due to new survey data. We reduced the minimum mapping unit from a 250-meter UTM grid to a 100-meter UTM grid. This allows for the grid to more closely follow watershed boundaries. Based on new survey results and reevaluation of arroyo toad habitat, additional stream reaches are included in this proposal, including sections of the Santa Clara River, Cajon Wash, Kitchen Creek, and Kinley Creek. The lengths of several streams included in proposed critical habitat are also reduced in several instances from the previous designation. These reductions occur where the likelihood of arroyo toad occupancy and the quality of arroyo toad habitat are low, such as along portions of Piru, San Francisquito, and Castaic Creeks. In addition, we have determined that habitat conditions in Arroyo Seco are not essential for the conservation of the species since closer scrutiny and comments from Forest Service biologists and USGS biologists indicate the stream gradient in Arroyo Seco is too steep for the arroyo toad. Consequently, we have not included this area in this proposal. New exclusions from critical habitat under section 4(b)(2) are contained in this proposed rule and discussed in the relevant exclusion sections.

Critical Habitat

Critical habitat is defined in section 3 of the Act. It receives protection under section 7 of the Act. Further information regarding the definition of critical habitat and how we implement related policies and regulations can be found in the
Federal Register
at 66 FR 9414.

Methods

Our methods for identifying the arroyo toad critical habitat included in this proposal are identical to the methods we used to make our final designation for this species on February 7, 2001 (66 FR 9414).

Primary Constituent Elements

In accordance with section 3(5)(A)(i) of the Act and regulations at 50 CFR 424.12, in determining which areas to designate as critical habitat, we consider those physical and biological features (primary constituent elements) that are essential to the conservation of the species, and that may require special management considerations or protection. These features are used for all listed species and include, but are not limited to: Space for individual and population growth and for normal behavior; food, water, or other nutritional or physiological requirements; cover or shelter; sites for breeding, reproduction, and rearing of offspring; and habitats that are protected from disturbance or are representative of the historic and geographical and ecological distributions of a species.

The specific biological and physical features, otherwise referred to as the primary constituent elements (PCEs), which comprise essential arroyo toad habitat are described below. These lands provide aquatic and terrestrial habitat essential for the maintenance of self-sustaining populations and metapopulations (a set of local populations or breeding sites within an area, where typically migration from one local population or breeding site to other areas containing suitable habitat is possible, but not routine) of arroyo toads throughout its range.

Space for Individual and Population Growth, and for Normal Behavior

The arroyo toad is found along medium-to-large-sized streams in coastal and desert drainages in central and southern California and Baja, Mexico. It occupies aquatic, riparian (areas near a source of water), and upland habitats in a reduced number of suitable drainages within its range. Essential habitat for the arroyo toad is created and maintained by the fluctuating hydrological, geological, and ecological processes operating in riparian ecosystems and the adjacent uplands. Periodic flooding that modifies stream channels, redistributes channel sediments, and alters pool location and form, coupled with upper terrace stabilization by vegetation, is required to keep a stream segment suitable for all life stages of the arroyo toad. Periodic flooding helps maintain areas of open, sparsely vegetated, sandy stream channels and terraces.

Eggs and tadpoles require aquatic habitat, as described below. Juvenile and adult arroyo toads require and spend much of their lives in riparian and upland habitats adjacent to breeding locations. Riparian habitats used by subadults and adults for foraging and burrowing include sand bars, alluvial terraces, and streamside benches that lack vegetation, or are sparsely to moderately vegetated. Upland habitats used by arroyo toads during both the breeding and nonbreeding seasons include alluvial scrub, coastal sage scrub, chaparral (shrubby plants adapted to dry summers and moist winters), grassland, and oak woodland. Arroyo toads also have been found in agricultural fields (Griffin
et al.
1999), but these lands may constitute sinks (areas where mortality rates are higher than reproduction rates) over the long term, due to tilling, pesticide and fertilizer applications, and heavy equipment use (Griffin and Case 2001).

The substrate in habitats preferred by arroyo toads consists primarily of sand, fine gravel, or pliable soil, with varying amounts of large gravel, cobble, and boulders. Areas that are damp and have less than 10 percent vegetation cover provide the best conditions for juvenile survival and rapid growth (Service 1999). Arroyo toads must be able to move between the stream and upland foraging sites, as well as up and down the stream corridor.

Food, Water, and Physiological Requirements

Arroyo toad tadpoles eat microscopic algae, bacteria, and protozoans sucked up from the spaces among pebbles, gravel, and sand or abraded from stones (Sweet 1992). Juveniles and adults feed on insects, but specialize on ants. When foraging, arroyo toads are often found around the driplines of oak trees. These areas often lack vegetation, yet have sufficient levels of prey. When active at night, toads often can be observed near ant trails feeding on ants, beetles, and other prey.

Cover or Shelter

During the day and other periods of inactivity, arroyo toads seek shelter by burrowing into the sand. Thus, areas of sandy or friable (readily crumbled) soils are necessary to burrow, but these soils can be interspersed with gravel or

cobble deposits. Arroyo toads may also seek temporary shelter under rocks or debris and have been found in mammal burrows on occasion. Upland sites with extremely compact soils can also be used for foraging and dispersal (D. Holland, in litt. 2000).

Sites for Breeding, Reproduction and Rearing of Offspring

The arroyo toad has specialized breeding habitat requirements. They favor shallow pools and open sand and gravel channels along low-gradient (typically less than 6 percent) reaches of medium-to-large-sized streams (Service 1999). These streams can have either intermittent or perennial streamflow and typically experience periodic flooding that scours vegetation and replenishes fine sediments. In at least some portions of its range, the species also breeds in smaller streams and canyons where low-gradient breeding sites are more sporadically distributed. Breeding pools must persist long enough for the completion of larval development (at least in most years), which is generally March through June, depending on location and weather. Sweet (1992) measured the average age to metamorphosis of arroyo toad larvae on the Los Padres National Forest at 71 days, with a predicted minimum of 62 days. Peak metamorphosis occurs during June and July in the northern part of the toad's range, and from late April through June further south, although it may be later, particularly at higher elevations (D. Holland, in litt. 2000).

Breeding arroyo toads lay their eggs in water over substrates of sand, gravel, or cobble in open sites such as overflow pools, old flood channels, and shallow pools along streams. Such habitats rarely have closed canopies over the lower banks of the stream channel due to periodic flood events. Heavily shaded pools are generally unsuitable for larval and juvenile arroyo toads because of lower water and soil temperatures and poor algal mat development. Pools less than 12 inches (30 centimeters (cm)) deep with clear water, flow rates less than 0.2 ft per second (5 cm per second), and bottoms composed of sand or well-sorted fine gravel are favored by adults for breeding and egg deposition (Sweet 1992). Larvae usually hatch in 4 to 6 days at water temperatures of 54 to 59 degrees Fahrenheit (12 to 16 degrees Celsius). Although egg strings are laid in very slow moving water, larvae (tadpoles) can be found in water velocities of up to 1.0 to 1.3 ft per second (30 to 40 cm per second) (Sweet 1992).

Disturbance, Protection, and the Historical Geographical Distributions

As a result of agriculture and urbanization, and the construction, operation, and maintenance of water storage reservoirs, flood control structures, roads, and recreational facilities such as campgrounds and off-highway vehicle parks, many arroyo toad populations have been reduced in size or extirpated (eliminated) due to extensive habitat loss from the 1920s into the 1990s. Although these factors have not dramatically reduced the range of the arroyo toad, within its range many of the habitats that were historically capable of supporting large numbers of arroyo toads have been lost in the last 100 years. Jennings and Hayes (1994) believe that the loss of habitat, coupled with the manipulation of water levels in many central and southern California streams and rivers, predation from introduced aquatic species, and habitat degradation from introduced plant species, caused arroyo toads to be extirpated from 76 percent of their previously occupied habitat in California. Through focused survey efforts over the past few years, a few new arroyo toad populations have been discovered. Because of these recent efforts, however, it is unlikely that many more populations remain undiscovered. The conservation and subsequent protection of the remaining arroyo toad populations are essential for its conservation (Service 1999).

Pursuant to our regulations, we are required to identify the known physical and biological features,
i.e.
, PCEs, essential to the conservation of the arroyo toad, together with a description of any critical habitat that is proposed. In identifying the PCEs, we used the best available scientific and commercial data available. The physical ranges described in the PCEs may not capture all of the variability that is inherent in natural systems that support arroyo toads. The PCEs determined essential to the conservation of arroyo toad include, but are not limited to:

1. Rivers or streams with hydrologic regimes that supply water to provide space, food, and cover needed to sustain eggs, tadpoles, metamorphosing juveniles, and adult breeding toads. Specifically, the conditions necessary to allow for successful reproduction of arroyo toads are:

a. breeding pools with areas less than 12 in (30 cm) deep;

b. areas of flowing water with current velocities less than 1.3 ft per second (40 cm per second); and

c. surface water that lasts for a minimum length of 2 months in most years,
i.e.
, a sufficient wet period in the spring months to allow arroyo toad larvae to hatch, mature, and metamorphose.

2. Low-gradient stream segments (typically less than 6 percent) with sandy or fine gravel substrates that support the formation of shallow pools and sparsely vegetated sand and gravel bars for breeding and rearing of tadpoles and juveniles.

3. A natural flooding regime, or one sufficiently corresponding to a natural regime, that will periodically scour riparian vegetation, rework stream channels and terraces, and redistribute sands and sediments, such that breeding pools and terrace habitats with scattered vegetation are maintained.

4. Riparian and adjacent upland habitats (particularly alluvial streamside terraces and adjacent valley bottomlands that include areas of loose soil where toads can burrow underground) to provide foraging and living areas for subadult and adult arroyo toads.

5. Stream channels and adjacent upland habitats that allow for migration to foraging areas, overwintering sites, dispersal between populations, and recolonization of areas that contain suitable habitat.

Arroyo toads are not distributed uniformly throughout the critical habitat units. Arroyo toad breeding habitat is patchily distributed along the stream courses, and the same is true of appropriate upland habitat. Some areas primarily provide for migration and dispersal between breeding and foraging habitats or allow for dispersal to additional breeding pools that will accommodate increased populations during favorable years. Habitat conditions within streams can change rapidly in response to streamflows and other factors, such as the development and shifting of sand and gravel bars, and creation and disappearance of pools. Terrace and upland habitats, although more stable than streambed and riparian habitats, may change as a result of rainfall, earthquakes, fires, and other natural events. These factors may cause the habitat suitability of given areas to vary over time, thus affecting the distribution of arroyo toads.

The combination of appropriate aquatic, riparian, and upland habitats forms ecologically functional units. These features and the lands that they represent are essential to the conservation of the arroyo toad. All lands identified as essential and proposed as critical habitat contain one or more of the PCEs for the arroyo toad.

Criteria Used To Identify Critical Habitat

The criteria we used to identify critical habitat are identical to the criteria outlined in the final designation previously published in the
Federal Register
on February 7, 2001 (66 FR 9414).

To evaluate our critical habitat model, we assessed its effectiveness at capturing documented toad locations from studies that focused specifically on surveying toads in upland habitats and studies involving radio telemetry. Holland and Sisk (2000) established extensive pitfall trap arrays at discrete distances from two stream courses and operated these arrays at various periods throughout the year. They had 466 captures of arroyo toads, 35 (7.5 percent) of which were identified as being in upland areas. Those toads were captured at distances that ranged from 49 to 3,855 ft (15 to 1,175 m) from the upland-riparian ecotone (boundary) (Holland and Sisk 2000). For the two areas sampled in that study (Cristianitos Creek and the upper Santa Margarita River), we found that our critical habitat boundaries encompassed an average of 76 percent of the pitfall trapping stations where arroyo toads were detected.

We also assessed studies that involved the tracking of arroyo toads with radio telemetry equipment. For example, in a number of studies by Ramirez (2002a, 2002b, 2002c, 2003), arroyo toads were tracked from the end of breeding activity until the commencement of aestivation, generally May through September. Cumulatively, these four studies involved the tracking of 77 adult arroyo toads in three separate critical habitat units in Orange, San Bernardino, and Los Angeles Counties. All but one of the numerous burrow sites chosen by these arroyo toads fell within our proposed critical habitat boundaries.

Proposed Critical Habitat Designation

The approximate area encompassing the proposed critical habitat by county and land ownership is shown in Table 1, and proposed critical habitat units for the arroyo toad in Table 2.

Table 1.—Approximate Critical Habitat in Acres (ac) (Hectares (ha)) by County and Land Ownership

County
Forest Service
BLM
FWS
Military
State/Local
Tribal
Private
Total

Monterey
0
0
0
6,453 ac (2,612 ha)
0
0
93 ac (38 ha)
6,546 ac (2,650 ha).

Santa Barbara
6,435 ac (2,604 ha)
0
0
0
0
0
4,553 ac (1,842 ha)
10,988 ac (4,446 ha).

Ventura
6,538 ac (2,645 ha)
0
0
0
0
0
1,105 ac (447 ha)
7,643 ac (3,092 ha).

Los Angeles
5,299 ac (2,144 ha)
27 ac (11 ha)
0
0
0
0
7,688 ac (3,111 ha)
13,014 ac (5,266 ha).

San Bernardino
2,631 ac (1,065 ha)
117 ac (47 ha)
0
2,594 ac (1,050 ha)
1,166 ac (472 ha)
0
9,306 ac (3,766 ha)
15,814 ac (6,400 ha).

Riverside
1,457 ac (589 ha)
1,047 ac (424 ha)
0
0
16 ac (6 ha)
0
966 ac (391 ha)
3,486 ac (1,410 ha).

Orange
483 ac (195 ha)
0
0
107 ac (43 ha)
2,135 ac (864 ha)
0
4,932 ac (1,996 ha)
7,657 ac (3,099 ha).

San Diego
9,949 ac (4,026 ha)
284 ac (115 ha)
755 ac (305 ha)
3,338 ac (1,351 ha)
3,544 ac (1,434 ha)
3,082 ac (1,247 ha)
52,613 ac (21, 292 ha)
73,565 ac (29,770 ha).

Total
32,792 ac (13,269 ha)
1,475 ac (597 ha)
755 ac (305 ha)
12,492 ac (5,056 ha)
6,861 ac (2,775 ha)
3,082 ac (1,247 ha)
81,256 ac (32,882 ha)
138,713 ac (56,133 ha).

Table 2.—Critical Habitat Units Proposed for the Arroyo Toad

Critical habitat unit
County
Acres
Ha

Northern

1. San Antonio River
Monterey
6,546
2,649

2. Sisquoc River
Santa Barbara
6,574
2,660

3. Upper Santa Ynez River Basin (including Indian Barbara and Mono Creeks)
Santa Barbara
4,414
1,786

4. Sespe Creek
Ventura
4,138
1,675

5. Piru Creek (Upper and Lower)
Ventura, L.A.
3,966
1,605

6. Upper Santa Clara River Basin (Castaic, San Francisquito Creeks)
Los Angeles
7,398
2,994

7. Upper Los Angeles River Basin (Big Tujunga, Mill, Alder Creeks)
Los Angeles
4,213
1,705

Southern

8. Black Star and Baker Creeks
Orange
172
69

9. San Jacinto River Basin/Bautista Creek
Riverside
683
277

10. San Juan Creek Basin (including Trabuco Creek)
Orange, Riverside
6,285
2,543

11. San Mateo Basin (Christianitos, Talega, Gabino, La Paz Creeks)
Orange, San Diego
4,580
1,853

12. Lower Santa Margarita Basin (De Luz, Roblar, Sandia)
San Diego
1,840
744

13. Upper Santa Margarita Basin (including Temecula and Arroyo Seco Creeks)
Riverside, San Diego
3,628
1,468

14. Lower and Middle San Luis Rey Basin (Pala, Keys Creeks)
San Diego
15,376
6,222

15. Upper San Luis Rey Basin (above Lake Henshaw)
San Diego
11,725
4,745

16. Santa Ysabel Creek (Santa Maria, Guejito, Temescal Creeks)
San Diego
11,080
4,484

17. San Diego River Basin (including San Vicente Creek)
San Diego
2,309
934

18. Sweetwater River Basin (Viejas and Peterson Creeks)
San Diego
9,235
3,737

19. Cottonwood Creek Basin (many tributaries)
San Diego
15,800
6,394

20. Upper Santa Anna River Basin/Cajon Wash
San Bernardino
1,263
511

Desert

21. Little Rock Creek (including Santiago Creek)
Los Angeles
941
381

22. Upper Mojave (West Fork, Deep, Horsethief, Little Horsethief)
San Bernardino
14,550
5,848

23. Whitewater River
Riverside
1,997
808

Critical habitat includes arroyo toad habitat throughout the species' range in the United States (
i.e.
, Monterey, Santa Barbara, Ventura, Los Angeles, Riverside, San Bernardino, Orange, and San Diego Counties, CA). Lands proposed for critical habitat designation are under private, local agency, county, State, Tribal, and Federal ownership, and have been divided into 23 Critical Habitat Units. Although all of the units we are proposing for critical habitat are within the geographic range of the species, we are not proposing all of the areas known to be occupied by the arroyo toad. We are not proposing any areas outside of the geographical area occupied by the species at the time it was listed. A brief description of each unit, and reasons why it is essential for the conservation of the arroyo toad, are presented below. The units are generally based on geographically distinct river basins. In several instances, a river basin has been broken into two or more units based on human or natural landscape features that effectively separate portions of the basin (
e.g.
, a large reservoir or gorge). Based on observations recorded since 1985, each unit is occupied by arroyo toads.

Jennings and Hayes (1994) estimate that arroyo toads have lost 76 percent of their historic habitat. Although the linear measure of historically occupied streams may not be 4 times what is currently occupied, museum records and data on extant populations indicate that the habitats capable of supporting large numbers of arroyo toads have decreased dramatically in the last 100 years. The reaches that typically support, or historically supported, the highest densities of toads are those in the lower and middle portions of river basins, usually associated with third order (a stream characterization based on size) or larger streams. Many of those reaches have been lost to, or degraded by, urban development, intensive agriculture, water diversions, sand and gravel mining operations, and reservoirs. As discussed in more detail below, with respect to the individual units, we find that all of the areas we are proposing for designation may require special management considerations or protections due to threats to the species and/or its habitat. Such management considerations and protections would benefit the arroyo toad and its habit because: Exotic predators and pets may eat or injure arroyo toads; unnatural water releases from dams can wash away arroyo toad eggs and tadpoles, promote the growth of exotic species, or reduce the availability of open sand bar habitat; water diversions can dry a streambed prior to the completion of metamorphosis from tadpole to toad; toads can be crushed by channel maintenance, road construction, or the plowing of agricultural fields with heavy machinery; toads can be trampled during recreational activities; arroyo toad habitat can be adversely affected by agricultural practices, the invasion of exotic species, inundation from water impoundments, or frequent human use; and water quality can be compromised by runoff from urban, industrial, or agricultural land uses. However, the designation of critical habitat does not carry with it any requirement that landowners or land managers implement any special management or protection programs.

Northern Region

The following seven critical habitat units are located in the Northern Region for the arroyo toad, as discussed in the Recovery Plan (Service 1999). Most of the lands are federally owned, and special management considerations and protections for the toad will likely be addressed through the section 7 consultation process and the development of management plans and conservation strategies. Because the toad populations in this unit have been reduced in size, and their habitat fragmented by road construction, dams, agriculture, and urbanization, it is essential to protect them to reduce further loss of genetic diversity and safeguard against the loss of any one population due to random natural or human-caused events. The Forest Service is the primary landowner of proposed critical habitat within the Northern Region. However, a very small proportion of Forest Service land in this region falls within critical habitat proposed for the arroyo toad.

Unit 1: San Antonio River, Monterey County

Unit 1 consists of the San Antonio River and adjacent uplands, from about 2 mi (3 km) upstream of the confluence with Mission Creek downstream to San Antonio Reservoir, a distance of about 17 mi (27 km), and includes small portions of Mission Creek and other tributaries. The unit encompasses approximately 6,546 ac (2,649 ha), of which more than 98 percent is on the Fort Hunter Liggett Military Reservation and the other 2 percent is privately owned.

The northernmost known population of arroyo toads is located here, and is approximately 100 mi (160 km) north of the nearest documented extant population. The onset of breeding activity along the San Antonio River has not been documented prior to the last week in April (Liz Clark, U.S. Army Reserve, pers. comm. 2003), which is several weeks later than the onset of breeding activity documented for arroyo toad populations on the Los Padres National Forest to the south (Sweet 1992). Arroyo toads in this unit may experience climatic conditions not faced by toads at sites found farther south. The protection of this area is essential to maintaining the complete genetic variability of the species and the full range of ecological settings within which it is found, which is essential to the ability of the arroyo toad to adapt to changing environmental conditions. Arroyo toads can be found along the entire length of this segment of the San Antonio River (Service 1999), which is still in a relatively natural state, consists of high-quality arroyo toad habitat, and supports probably one of the largest populations within the Northern Region. This area contains all the primary constituent elements, including breeding pools in low-gradient stream segments, sandy substrates, seasonal flood flows, and relatively undisturbed riparian habitat and upland benches for foraging and dispersal.

We consider other areas along the San Antonio River within Fort Hunter Liggett as essential for the conservation of the species, but excluded them from this proposal because they are within

mission-essential training areas (
see
Exclusions Under Section 4(b)(2)). Thus, we are proposing the majority of the essential lands along the San Antonio River as critical habitat, but we are excluding a portion of the essential lands (less than 50 percent), which are within mission-essential training areas on Fort Hunter Liggett (Army 2003). Military operations (including occasional troop movements and weed control) in and near the riparian zone, yet outside of mapped mission-essential training areas, may create the need for special management considerations in this unit.

Unit 2: Sisquoc River, Santa Barbara County

Unit 2 consists of 27 mi (43 km) of the Sisquoc River and adjacent uplands, from Sycamore Campground downstream to just below the confluence with La Brea Creek. The unit encompasses approximately 6,574 ac (2,660 ha), of which 61 percent is private land and 39 percent is within the Los Padres National Forest. Upper stretches of the river are within the National Forest and mostly within the San Rafael Wilderness Area. Below the National Forest boundary, the river and adjacent uplands are on rural private lands. This long, undammed stream is occupied arroyo toad habitat and is one of the few remaining major rivers in southern California with a natural flow regime. This area contains all of the primary constituent elements, including breeding pools in low-gradient stream segments, sandy or fine gravel substrates, seasonal flood flows, and relatively undisturbed riparian/upland habitat for foraging and dispersal. This area is essential to maintaining genetic diversity of the species. The protection of this population is essential as it is a core population. Grazing, sand and gravel mining, and limited recreational activities are the primary disturbances to arroyo toad habitat in this unit that may require special management considerations.

Unit 3: Upper Santa Ynez River Basin, Santa Barbara County

Unit 3 is located upstream of Gibraltar Reservoir and incorporates portions of the upper Santa Ynez River, Indian Creek, Mono Creek, and adjacent uplands. The unit encompasses approximately 4,414 ac (1,786 ha) within the boundaries of Los Padres National Forest, with 88 percent on National Forest lands and 12 percent on private non-residential inholdings. The segment of the upper Santa Ynez River proposed for designation extends 10 mi (16 km) from Jameson Reservoir downstream to Gibraltar Reservoir. Indian Creek is proposed from the Buckthorn Creek confluence down to its confluence with Mono Creek, a distance of approximately 5 mi (8 km). Mono Creek and associated uplands are proposed for designation for 7.5 mi (12 km) from the first unnamed stream below The Narrows to its confluence with the Santa Ynez River. This area contains all of the primary constituent elements, including breeding pools in low-gradient stream segments, sandy or fine gravel substrates, seasonal flood flows, and relatively undisturbed riparian/upland habitat for foraging and dispersal.

A large and well-studied arroyo toad population occurs in this area (Sweet 1992, 1993). It is likely a remnant of a much larger population that historically extended downstream below what is now Lake Cachuma and upstream into the area occupied by Jameson Reservoir. The population along Mono Creek is one of the more robust populations of arroyo toads on the Los Padres National Forest and is free of exotic vertebrate predators for much of its length (Jamie Uyehara, Forest Service, pers. comm. 2003). Unit 3 is also the wettest area occupied by arroyo toads in the Northern Region (Teale Data Center 1998; California Irrigation Management Information System 2000).

Arroyo toads in this unit likely experience precipitation and soil moisture conditions not faced by toads at drier sites. Potential adaptations to these conditions make the protection of this area essential to maintaining the genetic diversity of the species. Because it is within, or is surrounded by, National Forest land, this area has favorable habitat conditions for population persistence. The arroyo toad population inhabiting Mono and Indian Creeks is particularly healthy and could be used as a source for the reestablishment of arroyo toads in downstream reaches of the Santa Ynez River, if warranted. The leading threats to arroyo toads in this area, primarily along the lower Santa Ynez River and lower Mono Creek, are from exotic species, recreation, and problems associated with an upstream dam (
e.g.
, sediment trapping, altered hydrological regime, temperature changes). To ensure arroyo toad habitat in this unit is protected, special management considerations or protections may be needed.

Unit 4: Sespe Creek, Ventura County

Unit 4 includes 22 mi (35 km) of Sespe Creek and adjacent uplands, from the lower end of Sespe Gorge (elevation approximately 3,530 ft (1,076 m)) downstream to the confluence with Alder Creek. The unit encompasses approximately 4,138 ac (1,675 ha), of which 87 percent is on the Los Padres National Forest, primarily within the Sespe Wilderness. The remainder is in remote, private inholdings. One of the largest arroyo toad populations on the Los Padres National Forest occurs in this unit along Sespe Creek (Forest Service, in litt. 1999), which is undammed and retains its natural flooding regime. This core population is spread over large areas of excellent habitat, including numerous high-quality breeding pools, an abundance of sandy substrates, unimpeded seasonal flood flows, and relatively undisturbed riparian habitat and upland benches for foraging and dispersal (Service 1999). Up to several hundred adult arroyo toads inhabit this reach of the Sespe River (Sweet 1992, 1993), and during years of successful reproduction, such as 2003, thousands of juveniles can be found as well (Tom Murphy, Forest Service, pers. comm. 2003).

Arroyo toads have been found up to 3,300 ft (1,000 m) in elevation in this area, which is one of the highest known occurrences in the Northern Region. The arroyo toads in this unit likely experience temperature extremes or other environmental conditions not faced by toads at lower elevations. Potential adaptations to these conditions make the protection of this area essential for the maintenance of the genetic diversity of the species. In all likelihood, arroyo toad populations in units 4, 5, and 6 historically were part of a large Santa Clara River Basin metapopulation. Ecologically, these units provided a link between the more coastal populations on the Sisquoc and Santa Ynez Rivers, and populations in the Desert Region. Substantial barriers to toad movement now exist between these units, including dams, agriculture, and urban development. Impacts to the Sespe Creek habitat come from recreational activities and exotic predators. Special management considerations or protection may be needed to control and reverse these threats.

Unit 5: Piru Creek, Ventura and Los Angeles Counties

Unit 5 includes Piru Creek and adjacent uplands from the confluence with Lockwood Creek downstream to Pyramid Reservoir (Subunit 5a), and from the confluence with Fish Creek downstream to Lake Piru (Subunit 5b). Subunit 5b also includes Agua Blanca Creek from Devil's Gateway downstream to the confluence with Piru Creek. The unit encompasses approximately 3,966

ac (1,605 ha), 85 percent of which is within the Los Padres and Angeles National Forests, with the remaining on a few private inholdings. Subunit 5a is in a remote setting within the Los Padres National Forest, and most of subunit 5b is within the Sespe Wilderness.

Although much of the historical arroyo toad habitat along Piru Creek is now inundated by the two reservoirs, a substantial arroyo toad population occurs in this unit (Service 1999). The upper portion of subunit 5a is free of exotic vertebrate predators and the arroyo toad population there has been increasing and expanding over the past several years (J. Uyehara, pers. comm. 2003). The expansion of the population is likely due, in part, to seasonal campground closures and the elimination of suction-dredge mining. Because lower Piru Creek (subunit 5b) is below a large dam, the habitat there has experienced some degradation over the years from perennial water releases, rapid changes in flow volume, excessive flows during the breeding season, and an increased presence of exotic predators. However, future releases from Pyramid Dam are scheduled to more closely mimic natural flows and benefit the arroyo toad (Eva Begley, California State Division of Water Resources, pers. comm. 2003). This should result in an expanded, stable population distributed over areas of good-to-excellent habitat that is generally undisturbed by human activities. Both upper and lower Piru Creek contain all of the primary constituent elements, including breeding pools in low-gradient stream segments, sandy substrate, seasonal flood flows (modified to some extent below Pyramid Dam), and riparian habitat and upland benches for foraging and dispersal. Special management considerations may be required above and beyond those currently in place to address threats posed by horse and cattle grazing, recreation, and unnatural flows that could potentially be released from Pyramid Dam.

Unit 6: Upper Santa Clara River Basin, Los Angeles County

Unit 6 includes portions the Santa Clara River, Castaic Creek, San Francisquito Creek, and adjacent uplands. The unit encompasses approximately 7,398 ac (2,994 ha) of which 83 percent is private land and 17 percent is within the Angeles National Forest. Subunit 6a, predominantly within the Angeles National Forest, includes Castaic Creek from Bear Canyon downstream to Castaic Lake, and Fish Creek from Cienaga Spring to the confluence with Castaic Creek. Subunit 6b includes Castaic Creek from the downstream edge of The Old Road right-of-way (adjacent to Interstate 5) down to the confluence with the Santa Clara River, the Santa Clara River from the confluence with Bouquet Creek down to the confluence with Castaic Creek, and San Francisquito Creek from Drinkwater Canyon downstream to the confluence with the Santa Clara River. Subunit 6c includes the upper Santa Clara River from Arrastre Canyon downstream to the confluence with Bee Canyon Creek.

A healthy population of arroyo toads can be found on Castaic Creek above the reservoir (subunit 6a) (Bill Brown, Forest Service, pers. comm. 2003). Although unknown at the time the Recovery Plan was published (Service 1999), arroyo toads also occupy subunit 6b along the Santa Clara River. This portion of the Santa Clara River was originally excluded from designation as critical habitat for the arroyo toad, in part because we believed that a breeding population of arroyo toads could not be sustained in this area. Recent observations of arroyo toads, including eggs, prove this to be incorrect (Ruben Ramirez, Cadre Environmental, pers. comm. 2003). We had also previously stated (66 FR 9414) that the Natural River Management Plan (NRMP) (Valencia Company 1998) adequately protected this section of the Santa Clara River as a dispersal corridor. However, uplands along this section of the Santa Clara River remain unprotected and threatened by development. Because this section of the Santa Clara River supports a breeding population of arroyo toads, connects arroyo toad habitat in Castaic Creek with San Francisquito Creek, and is in need of further protection, we believe it is essential habitat for the arroyo toad metapopulation in the upper Santa Clara River Basin and, in turn, is essential for the conservation of the species.

Although not detected during a recent survey (Impact Sciences 2001), the Castaic Creek portion of subunit 6b contains high-quality arroyo toad habitat within its meandering floodplain and is connected to the occupied reach of the Santa Clara River. The habitat in this river segment is important to the long-term persistence of the Santa Clara River population by allowing for natural population expansion and fluctuation. Although previously included as critical habitat for the arroyo toad, the portion of Castaic Creek from The Old Road Bridge (adjacent to Interstate 5) upstream to Castaic Lagoon contains largely marginal to moderate quality habitat and is not included in this proposal. Arroyo toads have not been detected in this reach during recent surveys (Impact Sciences 2001). Although the habitat looks suitable for arroyo toads, they have not been detected during recent surveys in San Francisquito Creek, which empties into the Santa Clara River (Ed Ervin, U.S. Geological Survey (USGS), pers. comm. 2003). However, in 1997, calling arroyo toad males were heard along San Francisquito Creek near the old St. Francis Dam (Ian Swift, Mountains Recreation and Conservation Authority, pers. comm. 2003). In any event, lower San Francisquito Creek offers an excellent opportunity for further expansion of the arroyo toad population in subunit 6b and is important for the long-term persistence of the Santa Clara River population. The upper portion of the Santa Clara River (subunit 6c) supports a breeding population of arroyo toads (N. Sandburg, in litt. 2001; Rick Farris, Service, pers. comm. 2001; Frank Hovore, Hovore and Associates, in litt. 2001) and has the potential to greatly increase in size with appropriate protection.

Subunits 6a, 6b, and 6c contain all the primary constituent elements, including breeding pools in low-gradient stream segments, sandy substrates, seasonal flood flows, and riparian and upland habitats for foraging and dispersal. The majority of the lands within unit 6 are private, and arroyo toad habitat is adversely affected by urban development, agriculture, recreation, and mining. Exotic species are a concern here as well. Special management considerations or protection may be required in this unit to address these threats. This unit is the easternmost population in the Northern Region, and as such, provides the final link in the range of ecological settings for this region the maintenance of which is essential to the conservation of the species.

Unit 7: Upper Los Angeles River Basin, Los Angeles County

Unit 7 includes portions of Big Tujunga, Mill, and Alder Creeks, and adjacent uplands in the upper Los Angeles River Basin. The unit encompasses approximately 4,213 ac (1,705 ha), of which 64 percent is within the Angeles National Forest and 36 percent is on private lands. This unit is divided into two subunits. Subunit 7a includes 11.8 mi (19 km) of Big Tujunga Creek from below Big Tujunga Dam downstream to Hansen Lake. Subunit 7b encompasses: (1) Approximately 8 mi (13 km) of upper Big Tujunga Creek from immediately above Big Tujunga Reservoir upstream to 1.2 mi (2 km)

above the confluence with Alder Creek, (2) almost 3.7 mi (6 km) of Mill Creek from the Monte Cristo Creek confluence downstream to Big Tujunga Creek, and (3) 1.9 mi (3 km) of Alder Creek from the Mule Fork confluence downstream to Big Tujunga Creek.

Within the last 15 years, the drainages in this unit have been reported to be occupied by arroyo toads (Forest Service, in litt. 1996; Forest Service 2000; California Natural Diversity Data Base (CNDDB) 2003), and, collectively, these toads represent the only significant known population remaining in the coastal foothills of the San Gabriel Mountains. This unit is essential because it is occupied and contains several primary constituent elements including sandy low-gradient stream segments and highly braided river channels supporting sparse vegetation indicating periodic scouring (USGS 2002). Threats that may require special management considerations include adverse (
i.e.
, timing, amount) water releases from Big Tujunga Dam, exotic predators, such as crayfish and bullfrogs, and exotic plants, such as Arundo donax. This unit also contains populations that occur in high-elevation environments that are atypical for arroyo toad and that belong to a metapopulation of the species in the Northern Region.

Southern Region

The following 13 critical habitat units are located in the Southern Region for the arroyo toad and consist of a range of geographic locations from coastal regions to interior mountains. Arroyo toads probably occurred throughout the up- and downstream portions of each of these rivers and creek basins, but are now found only in segments of the rivers and creeks, due to loss or change of habitat and exotic predators. Each of these critical habitat units contains river basins that are identified in the Southern Region of the Recovery Plan (Service 1999). Conserving arroyo toad populations in these river basins is necessary for preserving the species' full range of genetic and phenotypic variation and is essential to the conservation of the species and may require special management considerations or protection.

Unit 8: Lower Santa Ana River Basin/Black Star and Baker Creeks, Orange County

Unit 8 includes portions of Black Star and Baker Creeks and adjacent uplands in the lower Santa Ana River Basin. The unit encompasses approximately 172 ac (70 ha) just above Irvine Lake, of which 92 percent is private land and 8 percent is within the Cleveland National Forest. We are proposing a 0.7 mi (1 km) stretch of Black Star Creek and associated uplands and a 1.5-mi (0.9-km) stretch of lower Baker Canyon and associated uplands upstream from the Cleveland National Forest boundary as critical habitat. We consider other high-quality habitats along Santiago Creek as essential but excluded them from this proposed rule because they are within the approved Orange County Central Coastal Subregion Natural Community Conservation Plan (NCCP)/Habitat Conservation Plan (HCP) area (see Discussion in Application of Section 4(a)(3)(B) and Exclusions Under Section 4(b)(2)).

Unit 8 is considered essential because it contains several primary constituent elements including shallow, exposed pools and open habitat with sandy terraces (Harmsworth Associates 2001), low-gradient stream segments with sandy washes, a natural flooding regime that periodically scours riparian vegetation and reworks stream channels and terraces, and riparian and adjacent uplands habitats that provide for foraging habitat and living areas for adult and subadult toads and dispersal between areas containing suitable habitat. Maintaining a population in this unit would enhance the viability of the larger arroyo toad metapopulation that extends across the lower coastal mountain slopes of the Santa Ana Mountains from Santiago Creek to San Mateo Creek (crossing into Units 10 and 11). Toads in this unit are significant to the overall conservation of the species because they are likely a relict population of a larger historical population that existed along the lower Santa Ana River Basin prior to the urbanization of the greater Los Angeles area. This relict population may contain unique genetic variation from a greater Santa Ana River Basin population that, with adequate protection and intermittent gene flow, would promote greater genetic diversity within the metapopulation. Toads were observed in lower Baker Canyon and at the confluence of Silverado Creek and Santiago Creek during the 1970s and 1980s (Robert Fisher, USGS, in litt. 1985; CNDDB 2003). However, surveys performed along Santiago Creek in 1997 failed to detect arroyo toads (Harmsworth Associates 1998), and reportedly no arroyo toads were detected in 2000 during surveys on Irvine Company land within this unit (Harmsworth Associates 2001). These survey efforts, however, did not cover all of the high-quality habitats that still exist within this unit (
e.g.
, upper reaches of Baker Canyon). Additional surveys are needed to determine the occupancy status of toads in this unit and their population size. Since suitable habitat still exists, special management considerations, such as augmenting or reestablishing toad populations, may be required for this unit. Threats that may require special management considerations include residential activities near the streams and past commercial sand and gravel removal operations.

Unit 9: San Jacinto River Basin / Bautista Creek, Riverside County

Unit 9 includes portions of Bautista Creek and adjacent uplands in the San Jacinto River Basin. The unit encompasses approximately 683 ac (276 ha), of which 98 percent is within the San Bernardino National Forest and the remaining 2 percent is on State land. We are proposing a 3.1-mi (5.1-km) discontinuous stretch of Bautista Creek as critical habitat. We also consider high-quality habitat along the San Jacinto River as essential from the Sand Canyon confluence downstream to the Soboba Indian Reservation border and along Bautista Creek from the San Bernardino National Forest boundary downstream to near the middle of section 27 (T5S, R1E), where the stream enters a debris basin, but excluded that area from the proposed critical habitat because it is within the Western Riverside MSHCP planning area (
see
Discussion in Application of Section 4(a)(3)(B) and Exclusions Under Section 4(b)(2)). There is also high-quality habitat on the Soboba Indian Reservation along the San Jacinto River and Indian Creek, as well as records of arroyo toads upstream from the Reservation along the San Jacinto River. However, there is uncertainty regarding the amount of high-quality habitat and its occupancy by arroyo toads on the Reservation, and therefore, whether this habitat is essential to the conservation of the species. As a consequence, we have not included lands within the Soboda Indian Reservation in the proposed rule. We are interested in working with the Soboba Indian Tribe in determining the occupancy of these areas and in developing a management plan that will address the conservation needs of the arroyo toad.

Unit 9 is comprised of a substantial arroyo toad population in Bautista Creek within the San Bernardino National Forest (USGS 2000, 2001). This population, along with another smaller population on the San Jacinto River (Brock Ortega, Dudek and Associates, in litt. 2001) which is being excluded from proposed critical habitat due to the

Western Riverside MSHCP, likely extends downstream onto Tribal and other private lands, and represents one of the easternmost populations within the species' range. Unit 9 is essential for arroyo toad conservation because it contains several primary constituent elements including low gradient sandy streambeds with slow moving water suitable for arroyo toad breeding and adjacent upland terrace for foraging and burrowing. The arroyo toad population in this unit is one of the easternmost populations and is isolated from other known populations to the south in the Santa Margarita Watershed, to the west in the San Juan Watershed, and from populations to the north in the Santa Ana Watershed. Therefore, conserving this population is important for the species' recovery because it may contain unique genetic, phenotypic and/or behavioral characteristics. The threats that may require special management considerations for this unit include destruction of habitat and mortality of individual toads from recreation and vehicular traffic from nearby roadways (USGS 2001).

Unit 10: San Juan Creek Basin, Orange County

Unit 10 includes portions of San Juan Creek, Bell Canyon, Trabuco Creek, and adjacent uplands in the San Juan Creek Basin. The unit encompasses approximately 6,285 ac (2,544 ha), of which 54 percent is private land, 34 percent is Orange County Park Land (Caspers Wilderness Park and O'Neill Regional Park), and 12 percent is within the Cleveland National Forest. Subunit 10a covers approximately 20.5 mi (33 km) of San Juan Creek from the bottom of Decker Canyon downstream to Interstate 5 and includes about 2.5 mi (4 km) of Bell Canyon from just below Crow Canyon downstream to the confluence with San Juan Creek. Subunit 10b covers approximately 5 mi (8 km) of Trabuco Creek from Falls Canyon to approximately 0.9 mi (1.4 km) downstream of the State Route 241 (Foothill Transportation Corridor) bridge.

Unit 10 supports a large core population in San Juan and Bell Creeks (P. Bloom, environmental consultant, in litt. 1998; USGS, in litt. 1999a; CNDDB 2003) that is concentrated within Caspers Wilderness Park and private lands downstream (P. Bloom in litt. 1998), the protection of which is essential for the conservation of the species. These areas contain several primary constituent elements, such as low-gradient stream segments with sandy or fine gravel substrates that support shallow pools and alluvial scrub habitat that provides foraging habitat. This unit also supports a population along a stretch of Trabuco Creek (D. Holland, in litt. 2000) where conditions such as low-gradient streams with shallow pools and adjacent upland habitat for foraging and burrowing are favorable for population persistence. Arroyo toad populations in this unit possibly belong to a greater arroyo toad metapopulation in the Santa Ana Mountains and may serve as an important linkage between toads in Santiago Creek (Unit 8) to the north and the San Mateo Creek Basin to the south. Threats to this population that may require special management considerations include exotic predators (bullfrogs), increased water diversions, and residual effects of recent gravel mining operations (Bloom 1998).

Unit 11: San Mateo Creek Basin, San Diego and Orange Counties

Unit 11 includes portions of San Mateo, Cristianitos, Talega, Gabino, and La Paz Creeks, and adjacent uplands in the San Mateo Creek Basin. The unit encompasses approximately 4,580 ac (1,854 ha), of which 68 percent is within portions of Marine Corps Base, Camp Pendleton (Camp Pendleton), including areas leased to outside parties for other land uses (
i.e.
, San Onofre State Park and agricultural lands) and adjacent cantonment areas; 1 percent is within the Cleveland National Forest; and 31 percent is on private land. This unit is divided into three subunits. Subunit 11a extends about 3.1 mi (5 km) from the Cristianitos Creek confluence downstream to just below Interstate 5. Subunit 11a also includes portions of Cristianitos Creek from just above Gabino Creek downstream to the confluence with San Mateo Creek. This subunit also includes approximately 3.1 mi (5 km) of Gabino Creek upstream from its confluence with Cristianitos Creek, including about 0.6 mi (1 km) of La Paz Creek, as well as approximately 2.7 mi (4.3 km) of Talega Creek upstream from its confluence with Cristianitos Creek and beyond the boundaries of Camp Pendleton. Subunit 11b covers approximately 0.4 mi (0.7 km) of San Mateo Creek beyond the boundaries of Camp Pendleton within the Cleveland National Forest near Devils Canyon, and subunit 11c covers approximately 3.9 mi (6.3 km) on San Onofre Creek within cantonment areas in Camp Pendleton. We consider other high-quality habitats along San Mateo, San Onofre, and Talega Creeks within Camp Pendleton as essential, but excluded them from this proposed rule because they are within mission-essential training areas (see Discussion of Exclusions Under Section 4(b)(2)).

This unit contains several primary constituent elements, including low-gradient stream segments with sandy or fine gravel substrates, shallow pools for breeding and rearing of tadpoles and juveniles, and riparian and adjacent uplands habitats for foraging and dispersal to other populations. With so many favorable habitat conditions, Unit 11 is able to support large core populations in San Mateo and Cristianitos Creeks (Holland and Goodman 1998; CNDDB 2003) and is essential for the species. An unusual and important aspect of this unit is its close proximity to the coast because nearly all of the historic near-coastal populations have been extirpated due to extensive urbanization and river channelization along the coastal regions of southern California. Distinctive climatic conditions near the coast may provide different selective pressures on toads in this area, and favor specific genetic characteristics that help maintain the genetic diversity of the species. Threats to this arroyo toad essential habitat that may require special management considerations include cumulative impacts from military and other human activities, including direct mortality from vehicle collisions and vehicular crossings of stream beds, fire, exotic predators, and invasive plants (Holland and Goodman 1998).

Unit 12: Lower Santa Margarita River Basin, San Diego County

Unit 12 includes approximately 8.7 mi (14 km) of the Santa Margarita River and adjacent uplands, including almost 2.1 mi (3.4 km) of De Luz Creek from the town of De Luz to the boundary of Camp Pendleton (Subunit 12a) in the lower Santa Margarita River Basin, and from the lower end of Temecula Canyon along the lower Santa Margarita River to the westernmost boundary between Camp Pendleton and the Naval Weapons Station Seal Beach Detachment Fallbrook (Fallbrook Naval Weapons Station) (Subunit 12b). The unit encompasses approximately 1,840 ac (745 ha), of which 17 percent is within the Fallbrook Naval Weapons Station, 1 percent is on State land, and 82 percent is on private land. We consider other high-quality habitats along the Santa Margarita River in the very northeastern corner of Camp Pendleton as well as further downstream from the Camp Pendleton/Fallbrook boundary as essential, but excluded them from this proposed rule because they are within mission-essential training areas on Camp

Pendleton (see Discussion of Exclusions Under Section 4(b)(2)).

Recent surveys of the Santa Margarita River and De Luz Creek immediately downstream of this unit on Camp Pendleton have documented what is probably the largest known population of arroyo toads (Holland 1995; Holland and Goodman 1998; Varanus Biological Services, Inc. 1999; Holland and Sisk 2001; CNDDB 2003). This unit contains several primary constituent elements including rivers with suitable hydrologic regimes, low-gradient stream segments with sandy substrates supporting shallow pools and gravel bars for breeding and rearing tadpoles and juveniles, and riparian and adjacent upland habitat to provide foraging and living areas for subadult and adult toads. This unit is important for the recovery of the species because of its size, proximity to other large populations on Camp Pendleton, and potential connectivity to populations in the upper Santa Margarita River Basin (Unit 13). Threats to this habitat that may require special management considerations include cumulative impacts to the species' habitat from military and other human activities, including direct mortality from vehicle collisions and vehicular crossings of stream beds, fire, exotic predators, and invasive plants (Holland and Goodman 1998).

Unit 13: Upper Santa Margarita River Basin, San Diego and Riverside Counties

Unit 13 is located upstream from Vail Lake and includes portions of Temecula and Arroyo Seco Creeks, and adjacent uplands in the upper Santa Margarita Basin. The unit encompasses approximately 3,627 ac (1,468 ha), of which 82 percent is private land, 17 percent is within the Cleveland National Forest, and 1 percent is BLM land. This unit is divided into two subunits. Subunit 13a includes 3.7 mi (5.9 km) of Arroyo Seco Creek from Crosley Homestead downstream to just north of the Riverside/San Diego County boundary and further downstream within the Cleveland National Forest. Subunit 13b includes approximately 7.2 mi (11.6 km) of Temecula Creek from Dodge Valley downstream to the Riverside/San Diego County boundary. We consider other high-quality habitats along Temecula, Wilson, and Arroyo Seco Creeks as essential, but excluded them from this proposed rule because they are within the Western Riverside MSHCP planning area (see Discussion in Application of Section 4(a)(3)(B) and Exclusions Under 4(b)(2)).

Unit 13 contains documented occurrences in Temecula, Wilson, and Arroyo Seco Creeks (AMEC Earth and Environmental, Inc. 2001; CNDDB 2003) and is essential because it contains high-quality habitat, such as broad, flat alluvial valleys with good foraging habitat, loose soils for burrowing, and shallow pools for breeding. The habitat conditions are favorable for population expansion and long-term persistence, and the unit provides a potential link to populations in the lower Santa Margarita River Basin (Unit 12). Sand mining operations and exotic predators (CNDDB 2003) threaten arroyo toad habitat in this unit and may require special management considerations.

Unit 14: Lower and Middle San Luis Rey River Basin, San Diego County

Unit 14 includes portions of the San Luis Rey River below Lake Henshaw and adjacent uplands, and includes sections of Pala and Keys Creeks in the lower and middle San Luis Rey River Basin. The unit encompasses approximately 15,376 ac (6,222 ha), of which 82 percent is private land, 12 percent (1856 ac (751 ha)) is on the Pala Indian Reservation, and 7 percent (1021 ac (413 ha)) is on the Rincon Indian Reservation. Approximately 30 mi (48 km) of the San Luis Rey River from the western edge of the La Jolla Indian Reservation downstream to the confluence with Guajome Creek near the City of Oceanside are proposed for designation. It also includes approximately 3.4 mi (5.5 km) of Pala Creek and 1.7 mi (2.7 km) of Keys Creek upstream from their confluence with the San Luis Rey River.

This long, low-elevation (all below 1,000 ft (305 m) in elevation) unit is situated in a broad, flat valley with a low-gradient river that supports shallow pools and sandy substrates in adjacent upland terraces for foraging and burrowing. This unit is essential for the recovery of the arroyo toad because it supports one of the largest core populations within the species' range (Dudek and Associates, Inc. in litt. 1995; Tierra Madre Consultants, Inc., in litt. 1995; California Department of Transportation (Caltrans) 1998; Varanus Biological Services, Inc., in litt. 1999; KEA Environmental, Inc., in litt. 2000). Special management considerations that are required in this unit include minimizing impacts from intensive urbanization, agriculture, exotic predators, and plants, and addressing issues regarding dams and water diversions in the upper end of the unit.

We are including lands on the Pala and Rincon Indian Reservations because they consist of some of the highest quality occupied habitat, such as low-gradient rivers containing shallow pools for breeding and upland habitat for foraging, in this unit (Tierra Environmental Services 1999; Varanus Biological Services, Inc. 1999). If these high-quality habitats on the Reservations are lost, the migration of individuals and continuity of gene flow along the San Luis Rey River would be precluded, resulting in fragmentation of remaining toad populations outside of the Reservations and their greater susceptibility to extirpation. The Service will be attempting to work closely with the Pala and Rincon Band of Mission Indians prior to the final designation of critical habitat to achieve necessary conservation measures for the species and to subsequently exclude the these Reservation lands from critical habitat. Designation of these Reservation lands is essential to the conservation of the species and may require special management considerations, such as minimizing development impacts in riparian areas and adjacent upland habitat.

Unit 15: Upper San Luis Rey River Basin, San Diego County

Unit 15 includes the upper San Luis Rey River above Lake Henshaw, two of its headwater tributaries, and adjacent uplands in the upper San Luis Rey River Basin. The unit encompasses approximately 11,725 ac (4,745 ha), of which 86 percent is private land and 14 percent is within the Cleveland National Forest. This unit consists of two subunits. Subunit 14a covers almost 8.7 mi (14 km) of the upper San Luis Rey River from the Indian Flats area downstream to the upper end of Lake Henshaw and includes about 7.8 mi (12.5 km) of Agua Caliente Creek from the western edge of section 13 (T10S, R3E) to the confluence with the San Luis Rey. Subunit 14b includes approximately 1.6 mi (2.5 km) of the West Fork of the San Luis Rey River, where it runs through Barker Valley. Arroyo toads occur in each of these drainages, with the largest concentration found along Agua Caliente Creek.

This unit is essential because it contains several primary constituent elements including low-gradient stream segments with sandy substrates supporting shallow pools, and riparian and adjacent upland habitats to provide areas foraging and burrowing. This unit is important for the recovery of the species because it contains a unique assemblage of several small, disjunct, high-elevation arroyo toad populations and one large, core population on Agua Caliente Creek (E. Gergus, San Diego State University, in litt. 1992; CNDDB 2003) in an area where in-stream and/or overland dispersal between

populations is likely still possible. Maintaining adequate genetic connectivity within this population increases the probability of these populations' long term persistence. Groundwater pumping on private lands, exotic predators, and grazing are the primary disturbances to arroyo toad habitat that may require special management in this unit.

Unit 16: Santa Ysabel Creek Basin, San Diego County

Unit 16 includes portions of Santa Ysabel Creek and adjacent uplands, and includes portions of Santa Maria Creek, Guejito Creek, and Temescal Creek (Pamo Valley) in the San Dieguito River/Santa Ysabel Creek Basin. The unit encompasses approximately 11,080 ac (4,484 ha), of which 93 percent is private land, 6 percent is within the Cleveland National Forest, and 1 percent is on the Mesa Grande Indian Reservation. The unit consists of four subunits. Subunit 16a includes approximately 7.9 mi (12.7 km) of Santa Ysabel Creek and adjacent uplands from the Mesa Grande Indian Reservation downstream to the western boundary of the Cleveland National Forest near Boden Canyon (which is the eastern boundary of the San Diego MSCP area). This subunit also includes approximately 4.3 mi (7 km) of Temescal Creek from the northern edge of Pamo Valley to the confluence with Santa Ysabel Creek and 0.1 mi (0.1 km) of Boden Canyon and adjacent uplands on the Cleveland National Forest at approximately 0.75 mi (1.2 km) upstream from the Santa Ysabel Creek confluence. Subunit 16b includes approximately 7.5 mi (12 km) of Guejito Creek from the 2,000-ft (610-m) elevation contour downstream to the San Diego MSCP boundary near San Pasqual Valley. Subunit 16c covers approximately 5.3 mi (8.5 km) of Santa Maria Creek from the west side of Ramona to the San Diego MSCP boundary near San Pasqual Valley. Subunit 16d includes approximately 5.2 mi (8.3 km) of Santa Ysabel Creek and adjacent uplands from approximately 0.5 mi (0.8 km) east of Highway 79 downstream to approximately 0.25 mi (0.4 km) downstream of the confluence with Witch Creek. We consider other high-quality habitats along Santa Ysabel, Santa Maria, and Guejito Creeks as essential, but excluded them from this proposed rule because they are within the approved San Diego MSCP plan area (see discussion in Application of Section 4(a)(3)(B) and Exclusions Under Section 4(b)(2) of the Act).

All of the drainages included in this unit are occupied by arroyo toads, and a large population exists along Temescal and Santa Ysabel Creeks within Pamo Valley (Varanus Biological Services, Inc. 1999; Tierra Environmental Services, in litt. 2001; USGS, in litt. 2002; CNDDB 2003). This unit is essential because it contains several primary constituent elements including low-gradient sandy stream segments with shallow pools for breeding and rearing of tadpoles, and upland sandy terraces that provide foraging and burrowing habitat. This unit is also essential for the species' recovery because it supports a large core population and contains several additional populations that are interconnected. In addition, this unit provides an important linkage for genetic interchange with a core arroyo toad population in the San Pasqual Valley, which is within the San Diego MSCP. A population of arroyo toads was recently discovered in high-quality habitat along Santa Ysabel Creek upstream from Lake Sutherland (USGS, in litt. 2002). Protection of this population, on the Santa Ysabel Open Space Preserve, and another population in Witch Creek (E. Gergus, in litt. 1992), a tributary of Santa Ysabel Creek, is essential for the recovery of the species because they exist in an undammed portion of the Santa Ysabel Creek drainage above Lake Sutherland and are thus subject to a more natural flooding regime. Within this portion of the upper Santa Ysabel Creek, approximately 40 ac (16 ha) of Mesa Grande Indian Reservation is included as critical habitat. This Reservation is located between occupied areas on the Santa Ysabel Open Space Preserve and the confluence of Witch and Santa Ysabel Creeks, which is downstream from where toads were discovered in Witch Creek in the early 1990s. Conserving habitat on the Mesa Grande Reservation is essential to allow for the migration of toads to support the genetic and demographic continuity within this population along the upper portions of Santa Ysabel Creek. Grazing, exotic predators, and urbanization (Tierra Environmental Services, in litt. 2001; CNDDB 2003) are the primary threats to this arroyo toad essential habitat that may require special management considerations in this unit.

Unit 17: San Diego River Basin/San Vicente Creek, San Diego County

Unit 17 includes portions of the San Diego River and San Vicente Creek and adjacent uplands in the San Diego River Basin. The unit encompasses approximately 2,309 ac (934 ha), of which 75 percent is private land, 19 percent is within the Cleveland National Forest, and 6 percent is on the Capitan Grande Indian Reservation. The unit is broken into four subunits—three disjunct sections of the San Diego River and one section of San Vicente Creek. Subunit 17a includes approximately 5 mi (8 km) of the San Diego River from Ritchie Creek downstream through 0.5 mi (0.9 km) of the Capitan Grande Indian Reservation to the upper edge of El Capitan Reservoir and approximately 0.6 mi (1 km) of lower Cedar Creek. Subunit 17b includes 0.9 mi (1.5 km) of the San Diego River from El Capitan Reservoir to El Monte County Park. Subunit 17c covers almost 4.3 mi (7 km) of the San Diego River from approximately 1.2 mi (2 km) below El Monte County Park downstream to the confluence with San Vicente Creek. Subunit 17d includes 1.4 mi (2.3 km) of San Vicente Creek from the west side of San Diego Country Estates downstream to where the creek crosses Wildcat Canyon Road (the MSCP area boundary). We consider other high-quality habitats along San Vicente Creek and the San Diego River as essential, but excluded them from this proposed rule because they are within the approved San Diego MSCP plan area (see Discussion in Application of Section 4(a)(3)(B) and Exclusions Under Section 4(b)(2)).

The upper San Diego River and San Vicente Creek are both occupied by arroyo toads (E. Gergus, in litt. 1992; Varanus Biological Services, Inc. 1999; CNDDB 2003). This unit is essential since it contains several primary constituent elements such as low-gradient stream segments with sandy substrates supporting shallow pools for breeding, riparian and adjacent upland habitats that provide foraging, living, and migration areas for subadult and adult toads. This unit is important for arroyo toad conservation because it encompasses several significant populations and includes suitable habitat for population expansion, thus increasing the probability of the long-term persistence of these populations. It also provides an important linkage to populations occurring within the San Diego MSCP area. This unit also includes high quality habitat, such as low-gradient stream segments and adjacent upland terrace areas for foraging and burrowing, on the Capitan Grande Indian Reservation along the upper portions of the San Diego River and above Capitan Reservoir. These areas are between areas of occupied high quality habitat outside of the Reservation along the San Diego River. Conserving habitat on the Capitan Grande Reservation is essential to allow for the migration of toads to support the

genetic and demographic continuity within this population on the upper portions of the San Diego River. Minimizing threats from development is necessary to maintain the viability of the populations in this unit. Consequently, special management considerations or protection may be required.

Unit 18: Sweetwater River Basin, San Diego County

Unit 18 includes portions of the Sweetwater River, Peterson Canyon, Viejas Creek, and adjacent uplands in the Sweetwater River Basin. The unit encompasses approximately 9,235 ac (3,737 ha), of which 54 percent is private land, 23 percent is on California State Park land, 12 percent is within the Cleveland National Forest, 8 percent is on the San Diego National Wildlife Refuge, 3 percent is on California Department of Fish and Game (CDFG) land, and less than 1 percent is on the Sycuan Indian Reservation. The unit is broken into four subunits—three disjunct sections of the Sweetwater River and one section of Viejas Creek. Subunit 18a covers approximately 20 mi (32 km) of the Sweetwater River from the top of Upper Green Valley in Cuyamaca Rancho State Park downstream to the San Diego MSCP area boundary. Subunit 18b includes approximately 0.7 mi (1.2 km) of the Sweetwater River between the MSCP boundary and Loveland Reservoir and 1.5 mi (2.4 km) of Peterson Canyon from just east of the Taylor Creek confluence downstream to the top of Loveland Reservoir. Subunit 18c encompasses approximately 16 mi (26 km) of the Sweetwater River, within the MSCP boundary, from immediately below Loveland Dam downstream to the upper edge of Sweetwater Reservoir. Subunit 18d covers 1.8 mi (2.9 km) of Viejas Creek and associated uplands from the western border of the Viejas Indian Reservation downstream to the Congressional boundary of the Cleveland National Forest (also the eastern boundary of the San Diego MSCP area). We consider other high-quality habitats along Viejas Creek and the Sweetwater River as essential, but excluded these lands from the proposed rule because they are within the approved San Diego MSCP plan area (
see
Discussion in Application of Section 4(a)(3)(B) and Exclusions Under Section 4(b)(2)).

The unit is essential to arroyo toad conservation because it consists of several primary constituent elements including open sandy river bottoms with shallow pools that support breeding populations and adjacent upland foraging and burrowing areas. This unit is also essential for the species conservation because it supports several significant populations over large stretches of rivers and streams (E. Gergus, in litt. 1992; Ervin and Griffin, in litt. 1997; Varanus Biological Services, Inc. 1999; CNDDB 2003). Maintaining suitable habitat conditions and connectivity are essential to provide for the long-term persistence of these populations. This unit also includes high quality habitat, such as low-gradient stream segments and adjacent upland terrace areas for foraging and burrowing, on the Sycuan Indian Reservation in the Sweetwater River. This area is between areas of occupied high quality habitat outside the Reservation along the Sweetwater River. Consequently, conserving habitat on the Sycuan Reservation is essential to allow for the migration of toads to support the genetic and demographic continuity within the population on this portion of the Sweetwater River. This unit may require special management considerations to address threats from adverse (
i.e.
, timing, amount) water releases from reservoirs, cattle grazing, gravel mining operations, off highway vehicular traffic, and exotic predators.

Unit 19: Cottonwood Creek Basin, San Diego County

Unit 19 includes portions of Cottonwood Creek, adjacent uplands, and portions of the following tributaries: Potrero Creek, Pine Valley Creek, Scove Canyon, Morena Creek, La Posta Creek, and Kitchen Creek of the Cottonwood Creek Basin. This large unit encompasses approximately 15,798 ac (6,393 ha), of which 55 percent is private land, 37 percent is within the Cleveland National Forest, 7 percent is on land owned by San Diego County, and 1 percent is on BLM land. The unit consists of four disjunct subunits—two sections of Cottonwood Creek and two sections of Pine Valley Creek. Subunit 19a covers 7 mi (11.2 km) of Cottonwood Creek from Buckman Springs (near Interstate 8) downstream to Morena Reservoir and includes approximately 3.7 mi (6 km) of La Posta Creek, 2.8 mi (4.5 km) of Morena Creek, and 5 mi (8 km) of Kitchen Creek upstream from the Cottonwood Creek confluence. Subunit 19b covers almost 9.9 mi (16 km) of Cottonwood Creek from approximately 2.5 mi (4 km) below Morena Reservoir downstream to State Highway 94 (excluding Barrett Reservoir) and includes 9.3 mi (15 km) of Potrero Creek from approximately the 2,466-ft (752-m) elevation benchmark downstream to the confluence with Cottonwood Creek. Subunit 19c covers about 7.5 mi (12 km) of Pine Valley Creek from the north edge of section 12 (T15S, R4E) downstream to approximately 0.6 mi (1 km) south of Interstate 8 and includes approximately 2.5 mi (4 km) of Scove Canyon and 0.6 mi (1 km) of Noble Creek. Subunit 19d encompasses 8 mi (13 km) of Pine Valley Creek from the Nelson Canyon confluence downstream to Barrett Reservoir. We consider other high-quality habitats along Cottonwood Creek as essential, but excluded them from this proposed rule because they are within the San Diego MSCP area (
see
Discussion in Application of Section 4(a)(3)(B) and Exclusions Under Section 4(b)(2)).

This unit encompasses a large number of distinct arroyo toad occurrences (E. Gergus, in litt. 1992; Varanus Biological Services, Inc. 1999; USGS, in litt. 1999b; CNDDB 2003) in an area where in-stream and/or overland dispersal between populations is probably still possible and where there is room for population expansion. It also provides an important linkage to populations occurring within the San Diego MSCP area. The unit is essential because it includes several primary constituent elements including wide, open sandy low-gradient stream segments supporting shallow pools for breeding and sparsely vegetated upland habitat for foraging and burrowing. Urbanization, grazing, Border Patrol activities, introduced plants, and exotic predators are the primary threats to this arroyo toad essential habitat that may require special management considerations.

Unit 20: Upper Santa Ana River Basin/Cajon Wash, San Bernardino County

Unit 20 includes approximately 4.8 mi (7.7 km) of Cajon Wash and adjacent uplands, from just south of Cajon campground downstream to the San Bernardino National Forest boundary. The unit encompasses approximately 1,262 ac (511 ha), of which 52 percent is private land and 48 percent is within the San Bernardino National Forest.

This population may represent some of the last vestiges of a much greater population that historically existed along the upper Santa Ana River Basin, but was almost entirely extirpated due to urbanization of the greater Los Angeles area. Arroyo toads were located near the junction between Lone Pine Canyon and Cajon Wash in 2000 (USGS 2000). The nearest known arroyo toad population occurs approximately 3.7 mi (6 km) (straight line distance) to the east in the West Fork Mojave River (Unit 22). However, the steep terrain between these populations makes it likely that

these populations are isolated from one another. Protecting this population is important for the conservation of the species because it helps preserve an important outlier segment of the genetic, phenotyopic, and/or behavioral variation of the species. This unit is essential because it contains several primary constituent elements including low-gradient sandy stream segments supporting shallow breeding pools, adjacent upland terraces for foraging and burrowing, and a flooding regime that sufficiently corresponds to natural conditions and periodically scours riparian vegetation and reworks stream channels. Recreational usage is the primary threat to this habitat that may require special management considerations.

Desert Region

Arroyo toad populations in the following three critical habitat units are essential for the conservation of the species in the Desert Region, as described in the Recovery Plan (Service 1999). Each of these units is isolated from each other and from any other units, making the issues of inbreeding, fragmentation, and random negative impacts of great concern. However, this unit also represents unique ecological conditions for arroyo toads, and likely harbors important genetic diversity.

Unit 21: Little Rock Creek Basin, Los Angeles County

Unit 21 includes approximately 5.9 mi (9.5 km) of Little Rock Creek and adjacent uplands, from the South Fork confluence downstream to the upper end of Little Rock Reservoir (in the vicinity of Rocky Point Picnic Ground), and approximately 1.1 mi (1.8 km) of Santiago Creek and adjacent uplands upstream from the confluence with Little Rock Creek in the Little Rock Creek Basin. The unit encompasses approximately 941 ac (381 ha), all of which is within the Angeles National Forest.

Unit 21 is essential for arroyo toad conservation because it supports several primary constituent elements including low-gradient sandy stream segments that support shallow breeding pools, adjacent upland areas for foraging, and a hydrologic regime that sufficiently corresponds to natural conditions and scours the riparian vegetation, thus providing open areas for movement. This unit is important for the conservation of the species because these populations collectively comprise an isolated population on the periphery of the species' range that possibly possesses unique genetic and phenotypic variation (Forest Service, in litt. 1998; Ramirez 2002a). Protecting peripheral populations is necessary for maintaining a broad range of genetic diversity for the species. Losses of diversity can result in reduced evolutionary flexibility and declines in fitness. Threats from recreational activities may require special management considerations to preserve the area's favorable habitat conditions for the persistence of this population.

Unit 22: Upper Mojave River Basin, San Bernardino County

Unit 22 includes portions of the Mojave River, the West Fork of the Mojave River, Horsethief and Little Horsethief Creeks, Grass Valley Creek, Deep Creek, and adjacent uplands in the upper Mojave River Basin. The unit encompasses approximately 14,450 ac (5,848 ha), of which 59 percent is private land, 18 percent is managed by the U.S. Army Corps of Engineers in association with a flood control reservoir, 14 percent is within the San Bernardino National Forest, 8 percent is State land, and 1 percent is BLM land. The unit is divided into three separate subunits. Subunit 22a includes: (1) Approximately 9.3 mi (18 km) of Deep Creek from near Holcomb Creek downstream to the confluence with the West Fork, (2) approximately 4 mi (6.5 km) of Little Horsethief Creek from near the western edge of section 28 (T3N, R5W) downstream to the confluence with Horsethief Creek, (3) approximately 3.4 mi (5.5 km) of Horsethief Creek from the Little Horsethief Creek confluence downstream to the West Fork confluence, (4) just over 4.3 mi (7 km) of the West Fork of the Mojave River from the Horsethief Creek confluence downstream to Mojave River Forks Dam, (5) approximately 2.5 mi (4 km) of the Mojave River below Mojave River Forks Dam, (6) approximately 1.4 mi (2.2 km) of Grass Valley Creek upstream from the confluence with the West Fork, and (7) approximately 2.8 mi (4.5 km) of Kinley Creek upstream from the Deep Creek confluence. Subunit 22b includes approximately 11 mi (18 km) of the Mojave River from just above the Upper Narrows (section 14, T5N, R4W) downstream to approximately 3.7 mi (6 km) below the Lower Narrows (section 13, T6N, R5W). Subunit 22c includes almost 1.9 mi (3 km) of the upper West Fork of the Mojave River, above Silverwood Lake, from near the 3,613 ft (1,462 m) elevation benchmark downstream to the upper end of the lake.

This unit is essential because it contains several primary constituent elements including low-gradient sandy stream segments that support shallow breeding pools, adjacent upland areas for foraging, and a hydrologic regime that sufficiently corresponds to natural conditions and scours the riparian vegetation, thus providing open areas for movements by toads. All of the drainages proposed for designation as critical habitat in this unit are occupied by arroyo toads, although the current occupancy of the Mojave River within subunit 22b is unknown (Tierra Madre Consultants, Inc. 1995; Ramirez 2002b; CNDDB 2003; Forest Service, in litt. 2003; Ramirez 2003). Habitat conditions within subunit 22b are favorable for toads (E. Ervin, pers. comm. 2003), with low-gradient pools, sandy substrates, scattered riparian vegetation, and undeveloped uplant habitats. Arroyo toads have been confirmed from this area as late as 1982 (Campbell
et al.
1996), and unconfirmed reports of calling arroyo toads have been made as recently as 1998 (Tim Thomas, Biologist, U.S. Fish and Wildlife Service, pers. comm.. 2003). However, it has not been extensively surveyed and recent arroyo toad observations are lacking along this reach.

Unit 22 is essential for arroyo toad conservation because it contains PCEs that support the largest population of the species on the desert side of the mountains (subunit 22a). Summit Valley, which encompasses the lower portions of Horsethief Creek and the West Fork of the Mojave River, is a broad, flat, alluvial valley that supports a substantial arroyo toad population (Ramirez 2003). Providing adequate and proper streamflows and protections for the upland alluvial habitats would increase the probability for the long-term persistence of this large toad population. If adequate streamflows and upland alluvial habitats can be maintained, this desert unit would have the most favorable conditions of any of the desert units for long-term persistence of the large toad population. The downstream portion of this unit contains the driest conditions of any unit proposed for arroyo toad critical habitat (Teale Data Center 1998; CIMS 2000), which suggests that this population may possess unique physiological adaptations, such as a reduced rate of evaporative water loss. Protection of this area is essential to maintain the range of genetic and phenotypic diversity of the species. The presence of exotic species, flood control and channel maintenance activities, and recreational activity (particularly off-road vehicle use) may create the need for special management in this unit.

Unit 23: Whitewater River Basin, Riverside County

Unit 23 includes approximately 7.2 mi (11.7 km) of the Whitewater River and adjacent uplands, from near Red Dome downstream to Interstate 10. The unit encompasses approximately 1,997 ac (808 ha), of which 52 percent is BLM land and 48 percent is private land. The current status of arroyo toads in this unit is poorly known. They were observed and photographed in the drainage in 1992 (Patten and Myers 1992) but were not detected in surveys conducted during the 2000 breeding season (Jones and Stokes, in litt. 2000). However, 2000 was generally a bad year for arroyo toad breeding activity, particularly in the southern half of the species' range, because of below average precipitation and subsequent low streamflows. In 2003, a tadpole was identified with almost complete certainty to be an arroyo toad near where the Colorado River Aqueduct crosses the river (P. Bloom, in litt. 2003). However, further surveys should be performed to confirm this finding. Given the relatively recent documentation of arroyo toads in this drainage, and the continued presence of suitable habitat in the area, we believe it is likely that this unit is still occupied.

Unit 23 supports primary constituent elements such as open sandy areas near small areas of slow moving water and adjacent sparse riparian habitat for foraging and burrowing. These essential PCEs support an isolated desert population on the easternmost periphery of the species' range in the Sonoran Desert that may possess unique phenotypic and genetic variation that are distinct from other desert populations in Units 21 and 22 in the Mohave Desert. Maintaining greater genetic diversity creates greater potential for adaptation to changing environmental conditions. Threats to this population that may require special management considerations include unsuitable water flow for breeding and off highway vehicular traffic.

Effects of Critical Habitat Designation

Section 7 Consultation

Section 7(a) of the Act requires Federal agencies, including the Service, to ensure that actions they fund, authorize, permit, or carry out do not destroy or adversely modify critical habitat. In our regulations at 50 CFR 402.02, we define destruction or adverse modification as “a direct or indirect alteration that appreciably diminishes the value of critical habitat for both the survival and recovery of a listed species. Such alterations include, but are not limited to: Alterations adversely modifying any of those physical or biological features that were the basis for determining the habitat to be critical.” However, in a March 15, 2001, decision of the United States Court of Appeals for the Fifth Circuit (
Sierra Club
v.
U.S. Fish and Wildlife Service et al.
, F.3d 434), the court found our definition of destruction or adverse modification to be invalid. In response to this decision, we are reviewing the regulatory definition of adverse modification in relation to the conservation of the species.

Section 7(a) of the Act requires Federal agencies, including the Service, to evaluate their actions with respect to any species that is proposed or listed as endangered or threatened and with respect to its critical habitat, if any is proposed or designated. Regulations implementing this interagency cooperation provision of the Act are codified at 50 CFR part 402. Section 7(a)(4) of the Act requires Federal agencies to confer with us on any action that is likely to jeopardize the continued existence of a proposed species or result in the destruction or adverse modification of proposed critical habitat. Conference reports provide conservation recommendations to assist the agency in eliminating conflicts that may be caused by the proposed action. The conservation recommendations in a conference report are advisory.

We may issue a formal conference report if requested by a Federal agency. Formal conference reports include an opinion that is prepared according to 50 CFR 402.14, as if the species were listed or critical habitat designated. We may adopt the formal conference report as the biological opinion when the species is listed or critical habitat designated, if no substantial new information or changes in the action alter the content of the opinion (
see
50 CFR 402.10(d)).

If a species is listed or critical habitat is designated, section 7(a)(2) requires Federal agencies to ensure that activities they authorize, fund, or carry out are not likely to jeopardize the continued existence of such a species or to destroy or adversely modify its critical habitat. If a Federal action may affect a listed species or its critical habitat, the responsible Federal agency (action agency) must enter into consultation with us. Through this consultation, we would ensure that the permitted actions do not destroy or adversely modify critical habitat.

If we issue a biological opinion concluding that a project is likely to result in the destruction or adverse modification of critical habitat, we also provide reasonable and prudent alternatives to the project, if any are identifiable. Reasonable and prudent alternatives are defined at 50 CFR 402.02 as alternative actions identified during consultation that can be implemented in a manner consistent with the intended purpose of the action, that are consistent with the scope of the Federal agency's legal authority and jurisdiction, that are economically and technologically feasible, and that the Director believes would avoid destruction or adverse modification of critical habitat. Reasonable and prudent alternatives can vary from slight project modifications to extensive redesign or relocation of the project. Costs associated with implementing a reasonable and prudent alternative are similarly variable.

Regulations at 50 CFR 402.16 require Federal agencies to reinitiate consultation on previously reviewed actions in instances where critical habitat is subsequently designated and the Federal agency has retained discretionary involvement or control over the action or such discretionary involvement or control is authorized by law. Consequently, some Federal agencies may request reinitiation of consultation or conference with us on actions for which formal consultation has been completed, if those actions may affect designated critical habitat or adversely modify or destroy proposed critical habitat.

Activities on Federal lands that may affect the arroyo toad or its critical habitat will require section 7 consultation. Activities on private or State lands requiring a permit from a Federal agency, such as a permit from the Corps under section 404 of the Clean Water Act, a section 10(a)(1)(B) permit from the Service, or some other Federal action, including funding (
e.g.
, Federal Highway Administration (FAA) or Federal Emergency Management Agency (FEMA) funding), will also continue to be subject to the section 7 consultation process. Federal actions not affecting listed species or critical habitat and actions on non-Federal and private lands that are not federally funded, authorized, or permitted do not require section 7 consultation.

Section 4(b)(8) of the Act requires us to evaluate briefly and describe, in any proposed or final regulation that designates critical habitat, those activities involving a Federal action that may adversely modify such habitat or that may be affected by such designation. Activities that may destroy or adversely modify critical habitat would be those that alter the primary constituent elements to the extent that

the value of critical habitat for the conservation of the arroyo toad is appreciably reduced. We note that such activities may also jeopardize the continued existence of the species.

Activities that, when carried out, funded, or authorized by a Federal agency, may affect critical habitat and require that a section 7 consultation be conducted include, but are not limited to:

(1) Regulation of activities affecting waters of the United States by the Corps under section 404 of the Clean Water Act;

(2) Regulation of water flows, damming, diversion, and channelization by any Federal agency;

(3) Road construction and maintenance, right-of-way designation, and regulation of agricultural activities on Federal lands (such as those managed by the Service, Forest Service, DOD, or BLM);

(4) Regulation of grazing, mining, and recreation by the BLM, DOD, Corps, or Forest Service;

(5) Regulation of airport improvement activities by the FAA;

(6) Military training and maneuvers, facilities operations, and maintenance on Fort Hunter Liggett and other DOD lands designated as critical habitat;

(7) Licensing of construction of communication sites by the Federal Communications Commission; and,

(8) Funding of activities by the U.S. Environmental Protection Agency (EPA), Department of Energy (DOE), FEMA, Federal Highway Administration (FHA), or any other Federal agency.

If you have questions regarding whether specific activities will constitute destruction or adverse modification of critical habitat, contact the Field Supervisor, Ventura Fish and Wildlife Office or Carlsbad Fish and Wildlife Office (
see

ADDRESSES
section). Requests for copies of the regulations on listed wildlife and inquiries about prohibitions and permits may be addressed to the U.S. Fish and Wildlife Service, Branch of Endangered Species, 911 NE 11th Ave., Portland, OR 97232 (telephone 503/231-2063; facsimile 503/231-6243).

All lands proposed for designation as critical habitat are within the geographic range of the species, all are occupied by the species (based on observations made within the last 20 years), and are likely to be used by the arroyo toad, whether for foraging, breeding, growth of larvae and juveniles, intra-specific communication, dispersal, migration, genetic exchange, or sheltering. Thus, we consider all proposed critical habitat units to be occupied by the species.

We recognize that the proposed designation of critical habitat may not include all of the habitat areas that may eventually be determined to be necessary for the recovery of the species. For these reasons, we want to ensure that the public is aware that critical habitat designations do not signal that habitat outside the proposed designation is unimportant or may not be required for recovery. Areas outside the proposed critical habitat designation will continue to be subject to conservation actions that may be implemented under section 7(a)(1) of the Act and to the regulatory protections afforded by the section 7(a)(2) jeopardy standard and the prohibitions of section 9 of the Act. 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, HCPs, or other species conservation planning efforts if new information available to these planning efforts calls for a different outcome.

Application of Section 4(a)(3)(B) and Exclusions Under Section 4(b)(2) of the Act

The recent amendments to Section 4(a)(3) of the Endangered Species Act (Pub. L. 108-136) address the relationship of Integrated Natural Resources Management Plans (INRMPs) to critical habitat. The new provision prohibits the Service from designating as critical habitat any lands or other geographical areas owned or controlled by the Department of Defense, or designated for its use, that are subject to an INRMP prepared under section 101 of the Sikes Act (16 U.S.C. 670a), if the Secretary of the Interior determines in writing that such plan provides a benefit to the species for which critical habitat is proposed for designation. Both Camp Pendleton and Fallbrook Naval Weapons Station have completed INRMPs. The application of section 4(a)(3) to these military lands and our decision to include them in this proposed designation are discussed below under
Relationship to Lands Managed by the DOD—Exclusions under Section 4(a)(3)(B) and 4(b)(2) of the Act.

Section 4(b)(2) of the Act states that critical habitat shall be designated, and revised, on the basis of the best available scientific data after taking into consideration the economic impact, the impact on national security, and any other relevant impact of specifying any particular area as critical habitat. An area may be excluded from critical habitat if it is determined that the benefits of exclusion outweigh the benefits of specifying the particular area as critical habitat, unless the failure to designate such area as critical habitat will result in the extinction of the species.

In our critical habitat designations, we use the provisions outlined in section 4(b)(2) of the Act to evaluate those specific areas that we are considering proposing as critical habitat as well as for those areas that are formally proposed for designation as critical habitat. We have excluded lands under section 4(b)(2) within military installations where designation could interfere with mission essential training activities or impact national security. In addition, we have excluded lands under section 4(b)(2) that are covered by the following types of plans if they provide assurances that the conservation measures they provide will be implemented and effective: (1) Legally operative HCPs that cover the species, (2) draft HCPs that cover the species and have undergone public review and comment (
i.e.
, pending HCPs), (3) Tribal conservation plans that cover the species, (4) State conservation plans that cover the species, and (5) National Wildlife Refuge System Comprehensive Conservation Plans.

We have considered, but are excluding from proposed critical habitat for the arroyo toad, the following areas under section 4(b)(2): Mission-essential training areas on Camp Pendleton and Fort Hunter-Liggett; lands within approved subarea plans of the San Diego Multiple Species Conservation Program (MSCP); and lands covered by the Orange County Central-Coastal NCCP/HCP, the San Diego Gas and Electric (SDG&E) NCCP/HCP, and the proposed Western Riverside Multiple Species Habitat Conservation Plan (MSHCP). We are proposing some lands that are managed by the DOD as critical habitat for the arroyo toad. These include nontraining and cantonment areas on Camp Pendleton, nontraining areas on Fort Hunter Liggett, and Fallbrook Naval Weapons Station. We are also proposing some Tribal lands within the Pala, Rincon, Sycuan, Mesa Grande, and the Capitan Grande Indian Reservation as critical habitat. Our evaluation of land within each of these categories under section 4(b)(2) follows.

Table 3 shows the approximate proposed critical habitat, essential area, and excluded areas. Table 4 shows the planning and preserve areas within NCCP/HCPs discussed in this proposal.

Table 3.—Approximate Proposed Critical Habitat, Essential, and Excluded Areas

Area considered essential
176,555 ac (71,450 ha).

Area excluded under 4(b)(2) (mission-essential training areas at Camp Pendleton and Fort Hunter Liggett; HCP plan areas consisting of San Diego MSCP, Central-Coastal Orange County NCCP/HCP, Proposed Western Riverside MSHCP, SDG&E NCCP/HCP)
37,842 ac (15,314 ha).

Proposed Critical Habitat
138,713 ac (56,133 ha).

Table 4.—HCP Areas Excluded From Proposed Critical Habitat

NCCP/HCP
Plan area
Preserve area

San Diego MSCP
582,000 ac (236,000 ha)
171,000 ac (69,572 ha).

Central-Coastal Orange County NCCP/HCP
208,713 ac (84,463 ha)
38,738 ac (15,667 ha).

Proposed Western Riverside MSHCP
1.3 million ac (530,0000 ha)
153,000 ac (61,919 ha).

SDG&E NCCP/HCP

Not specified
1

240 ac (97 ha).

1
The planning area for SDG&E's NCCP/HCP encompasses all of San Diego County west of the desert, a portion of Orange County within the existing SDG&E's service territory, and the SDG&E Moreno Compressor Station in Riverside County, California. However, the size of this planning area is not specified in SDG&E's Subregional Natural Community Conservation Plan. Based on the Plan's forecasting, it is estimated that SDG&E will impact 124 acres within 25 years following the receipt of their Section 10(a)(1)(B) permit. Since the future cannot be accurately predicted, the Service has authorized up to 400 acres (162 ha) of impact over a 55-year period under the Section 10(a)(1)(B) permit (USFWS 1995).

Approved Habitat Conservation Plans—Exclusions Under Section 4(b)(2)

Regional HCPs

Section 4(b)(2) of the Act requires us to consider other relevant impacts, in addition to economic impacts, when designating critical habitat. Section 10(a)(1)(B) of the Act authorizes us to issue permits for the take of listed wildlife species incidental to otherwise lawful activities. Development of an HCP is a prerequisite for the issuance of an incidental take permit pursuant to section 10(a)(1)(B) of the Act. An incidental take permit application must be supported by an HCP that identifies conservation measures that the permittee agrees to implement for the species to minimize and mitigate the impacts of the permitted incidental take.

HCPs vary in size and may provide for incidental take coverage and conservation management for one or many federally listed species. Additionally, more than one applicant may participate in the development and implementation of an HCP. Some areas occupied by the arroyo toad involve several very complex HCPs that address multiple species, cover large areas, and are very important to many participating permittees. Large regional HCPs expand upon the basic requirements set forth in section 10(a)(1)(B) of the Act because they reflect a voluntary, cooperative approach to large-scale habitat and species conservation planning. Many of the large regional HCPs in southern California have been, or are being, developed to provide for the conservation of numerous federally listed species and unlisted sensitive species and the habitat that provides for their biological needs. These HCPs are designed to proactively implement conservation actions to address future projects that are anticipated to occur within the planning area of the HCP. However, given the broad scope of these regional HCPs, not all projects envisioned to potentially occur may actually take place.

In the case of approved regional HCPs and accompanying Implementing Agreements (IAs) (
e.g.
, those sponsored by cities, counties, or other local jurisdictions) that provide for incidental take coverage for the arroyo toad, a primary goal of these regional plans is to provide for the protection and management of habitat essential for the species' conservation while directing development to other areas. The regional HCP development process provides an opportunity for more intensive data collection and analysis regarding the use of particular habitat areas by the arroyo toad. The process also enables us to conduct detailed evaluations of the importance of such lands to the long-term survival of the species in the context of constructing a system of interlinked habitat blocks that provide for its biological needs.

We have considered, but have not proposed as critical habitat, lands in approved subarea plans within the San Diego MSCP, the Central-Coastal NCCP/HCP in Orange County, and the SDG&E NCCP/HCP under Section 4(b)(2). These approved and legally operative HCPs include portions of five proposed critical habitat units (8, 16, 17, 18, and 19). We believe the benefits of excluding lands within these legally operative HCPs from the proposed critical habitat designations will outweigh the benefits of including them. The following represents our rationale for excluding these areas.

Portions of Unit 8 are excluded under section 4(b)(2) from proposed critical habitat because they are within the Orange County Central Coastal Subregional NCCP/HCP. The Central-Coastal NCCP/HCP in Orange County was developed in cooperation with numerous local and State jurisdictions and agencies, and participating landowners including the cities of Anaheim, Costa Mesa, Irvine, Orange, and San Juan Capistrano; Southern California Edison; Transportation Corridor Agencies; The Irvine Company; California Department of Parks and Recreation; Metropolitan Water District of Southern California; and the County of Orange. Approved in 1996, the Central-Coastal NCCP/HCP provides for the establishment of approximately 38,738 ac (15,677 ha) of reserve lands for 39 Federal or State listed and unlisted sensitive species within the 208,713 ac (84,463 ha) planning area. We issued an incidental take permit under section 10(a)(1)(B) of the Act that provides conditional incidental take authorization for the arroyo toad for all areas within the Central-Coastal Subregion except the Nor

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A04-9204. Public record. Not legal advice.