Endangered and Threatened Wildlife and Plants; Withdrawal of Proposed Rule To List Dudleya Blochmaniae ssp. Insularis, Dudleya sp. nov. ``East Point'', and Heuchera Maxima as Endangered

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AD39

Endangered and Threatened Wildlife and Plants; Withdrawal of

Proposed Rule To List Dudleya Blochmaniae ssp. Insularis, Dudleya sp.

nov. ``East Point'', and Heuchera Maxima as Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule; withdrawal.

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SUMMARY: The U.S. Fish and Wildlife Service (Service) withdraws the

proposal to list Dudleya blochmaniae ssp. insularis, Dudleya sp. nov.

``East Point'', and Heuchera maxima as endangered species under the

Endangered Species Act of 1973, as amended (Act). The Service finds

that information now available, discussed below, justifies withdrawal

of the proposed listings of these species as endangered. The National

Park Service (NPS) has implemented measures that significantly reduce

the risks to Dudleya blochmaniae ssp. insularis and Dudleya sp. nov.

``East Point'' and has sponsored field surveys that have identified a

greater abundance and distribution for Heuchera maxima. Based on this

information the Service concludes that listing of these species is not

warranted.

DATES: This withdrawal notice is made July 31, 1997.

ADDRESSES: The complete file for this rule is available for public

inspection, by appointment, during normal business hours at the Ventura

Field Office, U.S. Fish and Wildlife Service, 2493 Portola Road,

Ventura, California, 93003.

FOR FURTHER INFORMATION CONTACT: Tim Thomas, at the above address or by

telephone (805) 644-1766.

SUPPLEMENTARY INFORMATION:

Background

On July 25, 1995 the Service published in the Federal Register (60

FR 37993) a proposal to list 16 plant species from the northern Channel

Islands as endangered.

Included among these 16 taxa were Dudleya blochmaniae ssp.

insularis (Santa Rosa Island dudleya), Dudleya sp. nov. ``East Point''

(munchkin dudleya), and Heuchera maxima (Island alum-root), the subject

taxa of this notice of withdrawal. Santa Rosa Island dudleya (Dudleya

blochmaniae ssp. insularis) was first described as Hasseanthus

blochmaniae ssp. insularis by Reid Moran (1950a) based on a collection

made at ``Old Ranch Point'' on Santa Rosa Island in 1950. Moran (1953)

treated Hasseanthus as a subgenus of Dudleya; Hasseanthus had

previously been segregated from Dudleya on the basis of stem

characteristics and the presence of vernal (withering) leaves. In so

doing, he published the new combination Dudleya blochmaniae ssp.

insularis (Moran 1953). Though Thompson (1993) recently resegregated

Hasseanthus from Dudleya at the generic level, he provided no new

evidence for this action. Moreover, given that the base chromosome

number of Hasseanthus and Dudleya is the same (n=17) and that species

of Hasseanthus and Dudleya are completely interfertile but will not

cross with other family genera, splitting these taxa at the generic

level is inappropriate. As a result, the taxon will be recognized in

this notice of withdrawal under the name Dudleya blochmaniae ssp.

insularis.

Dudleya blochmaniae ssp. insularis is a small succulent perennial

in the stonecrop family (Crassulaceae). The plant has a corm-like root

structure, and 15 to 30 oblanceolate leaves in a basal rosette, from

which several flowering stems 3 to 7 centimeters (cm) (1.2 to 2.8

inches (in)) long arise. The white, five-petaled flowers and the

resulting fruits are fused at the base and wide-spreading distally.

This subspecies is distinguished from two other mainland subspecies of

D. blochmaniae on the basis of the more numerous rosette leaves,

shorter floral stems, more pronounced glaucousness of young floral

stems and their leaves, and the size and shape of the lower bracts

(Moran 1950a, Bartel 1993).

Dudleya blochmaniae ssp. insularis is only known from the type

locality near Old Ranch Point, also known as Marsh Point, on the east

end of Santa Rosa Island. The taxon occupies an area of less than 1

hectare (2 acres) of an

[[Page 41017]]

ancient marine terrace with a cobble surface, and associated with owl's

clover (Castilleja exserta), goldfields (Lasthenia californica), and

alien annual grasses, primarily Bromus and Vulpia species. The habitat

is relatively open with low densities of non-native annual grasses. In

1993, the number of individuals was estimated to be 2,000 (Rutherford

and Thomas, pers. obs. 1993). NPS and National Biological Survey (now

Biological Resources Division of the U.S. Geological Survey) staff

established demographic plots in 1994. In 1995 and 1996, the NPS

erected an electric fence around Skunk Point, including all habitat

occupied by D. blochmaniae ssp. insularis and a population of the

federally threatened snowy plover, during the spring and summer seasons

to eliminate potential damage from cattle. Cattle tracks and droppings

inside the exclosure indicate that entry has occurred in both years

(McEachern 1996). However, cattle were removed whenever found within

the fenced area and were not present long enough to adversely affect D.

blochmaniae ssp. insularis (Jim Hutton, Island Ranger, pers. comm.

1996). Breaks in the fence were repaired immediately.

Dudleya sp. nov. ``East Point'' was collected by Reid Moran in

1950. In his dissertation on the genus Dudleya, he included it in the

description of D. greenei, but remarked upon how it differed, and

described it as ``forma nana.'' Subsequent floras treated the form in

synonymy with D. greenei (Munz and Keck 1973, Smith 1976). In 1993,

Paul H. Thomson illegitimately published the name D. nana, based on the

description of forma nana in Moran's dissertation. An article

describing this new species has been submitted by Stephen McCabe to the

journal Madrono. This manuscript has been peer reviewed, the

description was found to meet the code requirements for valid

publication, and the reviewers felt that it was a distinct taxon

(Painter in litt. 1997).

Like Dudleya blochmaniae ssp. insularis described above, Dudleya

sp. nov. ``East Point'' is a small succulent perennial in the stonecrop

family (Crassulaceae). The plant has a short caudex-like stem, and

small, gray, ovate to oblanceolate leaves in a cluster of up to 20

basal rosettes, from which several flowering stems 2.5 to 7 cm (1 to

2.75 in) long arise. The pale yellow, five-petaled flowers are fused at

the base and spread only at the tips.

Dudleya sp. nov. ``East Point'' is known only from one population

comprising three colonies near East Point on Santa Rosa Island. The

colonies occur on a low windswept ridge with a cobble soil surface,

which is bereft of any other vegetation save scattered alien annual

grasses, small-flowered iceplant (Mesembryanthemum nodiflorum),

pineappleweed (Ambylopappus pusillus), and goldenbush (Lasthenia

californica). The uppermost colony covers 26 square meters, the middle

colony covers 88 square meters, and the lowermost colony covers 77

square meters (McEachern 1994). The total number of individuals in the

three colonies has been estimated to be 3,200 (S. McCabe, pers. comm.

1994). In 1994, the NPS constructed a fence around the population to

reduce browsing and trampling impacts, and to eliminate vehicle access

to the middle colony. Observations by researchers indicate the

following: the fencing has excluded cattle but not deer; the number of

seedling plants was higher in late winter of 1995 than in May, a few

months later, which may indicate a high seedling recruitment rate but a

low seedling survivorship rate; and several inflorescences were clipped

off by an unknown predator, possibly mice or insects (McEachern 1996).

A low seedling survivorship rate is common among wild plants and is

unlikely to pose a significant threat to a perennial species, which

needs only to replace itself once over a period of many years to

maintain a stable population size. A small fire burned vegetation

surrounding the lower colony, but did not appear to damage the dudleya

where the fuels are so light that fire cannot carry through the site.

Heuchera maxima (island alumroot) was described by E.L. Greene

(1886a) based on collections from the ``northward slope of Santa Cruz

Island.'' This nomenclature was retained in the most recent treatment

of the genus (Elvander 1993). Heuchera maxima is a perennial herb in

the saxifrage (Saxifragaceae) family. The round basal leaves are up to

7 cm (2.8 in) broad on long petioles up to 25 cm (10 in) in length. The

flowering stalks are up to 6.1 decimeters (dm) (2 ft) long and

scattered with small white-petaled flowers (Hochberg 1980b). No other

Heuchera species occurs on the islands; however, young plants of H.

maxima can resemble species of Jepsonia, Lithophragma, or Saxifraga

that occurs on the islands. Heuchera maxima can be distinguished from

these other taxa by its larger size at maturity, and flowers with ten

stamens rather than five.

Heuchera maxima grows primarily on moist, shady, north-facing

canyon bottoms, walls, and sea cliffs, but occurs in a few interior

localities as well. Collections of Heuchera maxima were made from Santa

Rosa Island by Hoffmann in 1929 and Dunkle in 1939; however, locality

information for these collections is vague. More recently, the plant

was collected from Cherry, Lobos, Ranch, and Windmill Canyons on Santa

Rosa Island (Rutherford and Thomas 1994). It was relocated in three of

those canyons during the 1994-1996 surveys, during which 27 additional

populations with up to 150 plants in each were found (McEachern and

Wilken 1996). H. maxima is also known from 11 locations on West Anacapa

Island (Rutherford and Thomas 1994; S. Junak, in litt. 1984). On Santa

Cruz Island, 16 populations with up to 170 plants per population have

been reported from the west half of the northern shore (McEachern and

Wilken 1996).

Summary of Comments and Recommendations

In the July 25, 1995, proposed rule (60 FR 37933) and associated

notifications, all interested parties were requested to submit factual

reports or information to be considered in making a final listing

determination. An initial 75-day comment period closed on October 9,

1995. A second 30-day comment period closed on February 21, 1997.

Appropriate Federal and State agencies, local governments, scientific

organizations, and other interested parties were contacted and asked to

comment. In accordance with Service policy published on July 1, 1994

(59 FR 34270), three appropriate and independent specialists were

solicited regarding pertinent scientific or commercial data and

assumptions relating to the proposed rule. Legal notices of the

availability of the proposed rule were published on August 5, 1995, in

the Santa Barbara News-Press and on August 11, 1995, in the Los Angeles

Times.

The Service received 14 letters concerning the proposed rule during

the comment periods, including those of one State agency and 11

individuals or groups. Because of the two public comment periods, some

individuals or groups commented twice. Because the proposed rule

included 16 plant taxa, only those comments specific to the three taxa

addressed in this notice are discussed here. Comments not specific to

these three taxa and general comments relevant to the proposed rule are

discussed in a separate final rule published in today's Federal

Register (Vol. 62 No. 147, July 31, 1997).

The Service has reviewed all of the written comments received

during both comment periods and status reports and

[[Page 41018]]

population surveys that occurred in between the comment periods. Four

commenters supported the listing proposal for the three taxa, one

opposed their listing, and seven stated no specific opinion on the

three taxa considered herein. Several commenters provided additional

information and other clarifications that have been incorporated into

the ``Summary of Factors'' section of this notice. Several comments

dealt with matters of opinion or legal history, which were not relevant

to the listing decision. The Service carefully considered all comments

and information submitted relevant to this decision to withdraw the

proposed listing. The Service response to those commenters supporting

listing of these taxa can be found in the ``Summary of Factors''

section. Comments submitted are available for review at the Ventura

Field Office (see ADDRESSES).

Summary of Factors Affecting the Species

The Service must consider five factors described in section 4(a)(1)

of the Act when determining whether to list a species. These factors,

and their application to the Service's decision to withdraw the

proposal to list Dudleya blochmaniae (Eastw.) Moran ssp. insularis

(Moran) Moran, Dudleya sp. nov. ``East Point'' S. McCabe, and Heuchera

maxima Greene, are as follows:

A. The Present or Threatened Destruction, Modification, or Curtailment

of Its Habitat or Range

The single most important loss of resources to insular ecosystems

is the loss of soils, as the soils are the foundation for the unique

island ecosystems and the insular endemic species found within them.

This loss of soils is the result of historic grazing and browsing by

sheep, goat, cattle, deer, elk, and bison, and rooting by pigs on the

various islands starting in the early 1800's, and in certain cases,

continuing today. Fencing installed by the NPS to exclude cattle from

the two Dudleya taxa populations has significantly reduced the threat

of soil loss in the habitat of these species. Cattle trampling,

previously known to remove large numbers of Dudleya sp. nov. ``East

Point'' plants, is no longer a significant threat. No cattle have

broken through the fence at East Point. Although cattle have on several

occasions gained access to the fenced areas through breaks in the fence

where Dudleya blochmaniae ssp. insularis occurs, NPS staff has

immediately removed the cattle upon discovery with no adverse impacts.

Although deer and elk are not excluded by the fencing (Painter, in

litt., 1997), the Service believes that the impacts of these animals on

the habitat for the two Dudleya species, in the absence of cattle, do

not constitute a significant threat to the survival of these taxa. Both

of the Dudleya populations occur on sites that are not favorable to

either elk or deer utilization. If elk or deer do enter these areas, it

is in limited numbers and for brief periods of time. Most of the

habitat currently occupied by Heuchera maxima is out of reach of the

effects of the trampling influence of the non-native mammals on the

islands (McEachern and Wilken 1996).

B. Overutilization for Commercial, Recreational, Scientific, or

Educational Purposes

In the horticultural trade, Dudleya have, in particular, been

favorite collector species. Dudleya sp. nov. ``East Point'' was

collected and introduced into the horticultural trade long ago as

``white sprite.'' Dudleya blochmaniae ssp. insularis though not in the

trade, has been cultivated by Dudleya enthusiasts. While the limited

distribution of these two taxa makes them of interest to such

enthusiasts, in the absence of the larger combined threats of cattle

trampling, collection alone does not pose a significant threat to these

species. Heuchera maxima is also found in cultivation. Although the

extent of collection of this taxon is uncertain, the Service believes

that the threat from overcollection is insignificant given the number

of populations of the species that are now known.

C. Disease or Predation

Disease is not known to be a factor affecting the taxa considered

in this rule. Grazing by cattle was identified as a threat in the

proposed rule. Consumption of individual plants by grazing animals has

been known to impact the reproduction of these plants and has had other

effects, such as trampling, erosion (see Factor A) and the introduction

of non-native species (see Factor E). The fencing constructed to

protect Dudleya blochmaniae ssp. insularis and Dudleya sp. nov. ``East

Point'' populations from cattle has reduced the level of herbivory on

these two taxa to where it no longer constitutes a significant threat

to the survival of these species. The majority of the Heuchera maxima

occur out of the reach of the effects of most non-native mammals on the

islands (McEachern and Wilken 1996).

D. The Inadequacy of Existing Regulatory Mechanisms

The Service evaluated existing Federal, State, and local regulatory

mechanisms prior to preparing the proposed rule for listing the two

plant taxa. The Service found evidence of inadequacy of the existing

regulatory mechanisms at that time. These regulatory mechanisms

included: (1) Listing under the California Endangered Species Act

(CESA); (2) the California Environmental Quality Act (CEQA) and

National Environmental Policy Act (NEPA); (3) conservation provisions

under section 404 of the Federal Clean Water Act and Section 1603 of

the California Fish and Game Code; (4) occurrence with other species

protected by the Federal Endangered Species Act; (5) land acquisition

and management by Federal, State, or local agencies, or by private

groups and organizations; and (6) local laws and regulations. The

Service believes that actions taken by the NPS for the protection of

Dudleya blochmaniae ssp. insularis and Dudleya sp. nov. ``East Point''

are sufficient to assure that regulatory mechanisms are adequate to

protect these two plant taxa. Heuchera maxima is now known to be

present in a sufficient number of populations (McEachern and Wilken

1996) so that any inadequacies of these regulatory mechanisms no longer

pose a significant threat to this species.

E. Other Natural or Manmade Factors Affecting Its Continued Existence

Introduced species of grasses and forbs have invaded many of

California's plant communities. Such weedy species can displace the

native flora by out-competing them for nutrients, water, light, and

space. Weedy plant invasions are facilitated by disturbances such as

grazing, developments, and various recreational activities.

Grazing by livestock typically changes the composition of native

plant communities by reducing or eliminating species that cannot

withstand trampling and predation (see Factors A and C), and enabling

more resistant (usually alien) plant species to increase in abundance.

Seed from non-sterile hay and animal feces increases the likelihood of

invasion of exotic species and prevents re-establishment of native

plants. Exotic species may flourish with grazing and may reduce or

eliminate native plant species through competition for resources. The

invasion of non-native species into the habitats of Dudleya blochmaniae

ssp. insularis and Dudleya sp. nov. ``East Point'' was cited as a

significant threat to these populations in the proposed rule

[[Page 41019]]

primarily due to the ongoing effects of alien mammals on these

habitats. Due to the fencing installed by the NPS, these impacts have

been reduced to the point that they no longer pose a significant threat

to the survival of these taxa. With over 50 recently reported

populations, Heuchera maxima is now known to occur in greater abundance

than was previously known and, due to the discovery of these additional

populations, the Service believes that this species is no longer

threatened with extinction.

Because Dudleya blochmaniae ssp. insularis and Dudleya sp. nov.

``East Point'' are both known only from single populations with few

individuals, they remain vulnerable to extinction due to random events,

such as drought, and storms. Neither taxon has ever been reported to

occur at any locality other than the single sites to which it is

currently restricted. Pro-active recovery efforts to lessen the threat

of such random events typically involve the establishment of additional

populations, but Service policy precludes the introduction of listed

species outside their historic range without specific approval from the

Director. To lessen the vulnerability of these taxa to random events,

the NPS has proposed to establish a seed banking program (NPS 1997).

Because of the low probability of such a random event taking place, the

significance of the threat from such an event in the absence of other

factors, is insufficient to warrant listing of these species. Heuchera

maxima is now known to occur in sufficient numbers that threats

resulting from few, small populations are no longer of concern.

Finding and Withdrawal

After a thorough review and consideration of all information

available the Service has determined that listing of Dudleya

blochmaniae ssp. insularis, Dudleya sp. nov. ``East Point'' and

Heuchera maxima as endangered is no longer warranted. The Service has

carefully assessed the best scientific and commercial information

available in the development of this withdrawal notice. Fencing

installed by the NPS since the time of the proposed rule has

sufficiently reduced the threats of soil loss, trampling and herbivory

by cattle and non-native mammals, and the invasion of competitive alien

weeds into habitat of the two dudleya species so that listing is no

longer warranted. Other factors cited in the proposed rule, including

overcollection, inadequate regulatory mechanisms, and extinction from

random events, are of insufficient magnitude to warrant listing in the

absence of any significant threat from other factors. Heuchera maxima

is now known to occur in more than 50 populations and the Service now

believes that this species is no longer threatened with extinction. A

final rule listing the other 13 plant taxa included in the original

proposed rule is published in the Federal Register concurrently with

this notice of withdrawal of the proposal to list Dudleya blochmaniae

ssp. insularis, Dudleya sp. nov. ``East Point'' and Heuchera maxima.

References Cited

A list of all references cited herein is available upon request

from the U.S. Fish and Wildlife Service Ventura Field Office (see

ADDRESSES section).

Author: The primary author of this withdrawal notice is Tim Thomas,

Ventura Field Office (see ADDRESSES section).

Authority

The authority for this action is section 4(b)(6)(B)(ii) of the

Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

List of Subjects in 50 CFR Part 17

Endangered and threatened species, Exports, Imports, Reporting and

recordkeeping requirements, Transportation.

Dated: July 24, 1997

John G. Rogers,

Director, U.S. Fish and Wildlife Service.

[FR Doc. 97-20132 Filed 7-30-97; 8:45 am]

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