Endangered and Threatened Wildlife and Plants; Proposed Rule To List the Plant Lesquerella Thamnophila (Zapata Bladderpod) as Endangered

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AE54

Endangered and Threatened Wildlife and Plants; Proposed Rule To

List the Plant Lesquerella Thamnophila (Zapata Bladderpod) as

Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: The Fish and Wildlife Service (Service) proposes to list the

plant Lesquerella thamnophila (Zapata bladderpod) as an endangered

species under the Endangered Species Act of 1973, as amended (Act).

Lesquerella thamnophila is known from four locations in Zapata and

Starr Counties, Texas. This species is threatened by increased urban

development, highway construction, increased oil and gas

activities, alteration and conversion of native plant communities to

improved pastures, overgrazing, and vulnerability from low population

numbers. This proposal, if made final, will extend the Act's protection

to Lesquerella thamnophila. Designation of critical habitat is not

being proposed because the Service has determined such designation is

not prudent.

DATES: Comments from all interested parties must be received by March

23, 1998. Public hearing requests must be received by March 9, 1998.

ADDRESSES: Comments and materials concerning this proposal should be

sent to the Field Supervisor, U.S. Fish and Wildlife Service,

Ecological Services Field Office, c/o Texas A&M University-Corpus

Christi, Campus Box 338, 6300 Ocean Drive, Corpus Christi, Texas 78412.

Comments and materials received will be available for public

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

address.

FOR FURTHER INFORMATION CONTACT: Field Supervisor of the Corpus Christi

Ecological Services Field Office in Corpus Christi, Texas. (Telephone

512-994-9005; Facsimile 512-994-8262).

SUPPLEMENTARY INFORMATION:

Background

ive, Corpus Christi, Texas 78412.

Comments and materials received will be available for public

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

address.

FOR FURTHER INFORMATION CONTACT: Field Supervisor of the Corpus Christi

Ecological Services Field Office in Corpus Christi, Texas. (Telephone

512-994-9005; Facsimile 512-994-8262).

SUPPLEMENTARY INFORMATION:

Background

Lesquerella thamnophila, a member of the mustard family, was first

collected in Zapata County, Texas by R.C. Rollins in 1959. The species

was named Lesquerella thamnophila in 1973 by R.C. Rollins and E.A. Shaw

in their work on the genus Lesquerella (Rollins and Shaw 1973). The few

collected specimens of Lesquerella thamnophila have all come from

Zapata and Starr Counties in southern Texas.

Lesquerella thamnophila is a pubescent, somewhat silvery-green

herbaceous perennial plant with sprawling stems 43-85 centimeters (cm)

(16-32 inches (in)) long. It has narrow basal leaves 4-12 cm (1.5-4.7

in) long and 7-15 millimeters (mm) (0.3-0.6 in) wide, with entire to

wavy or slightly toothed margins. The stem leaves are 3-4 cm (1-1.5 in)

long and 2-8 mm (0.1-0.3 in) wide, with margins similar to the basal

leaves. The inflorescences, usually appearing in April but dependent

upon the timing of spring rains, are loose racemes of yellow-petaled

flowers. Fruits are round and 4.5-6.5 mm (0.2-0.8 in) in diameter on

short downward curving pedicels (Poole 1989).

Lesquerella thamnophila occurs on level to sloping terrain in

gravelly to sandy-loam upland terrace or Rio Grande floodplain soils.

Known locations are associated with three Eocene-age geologic

formations--the Jackson, Laredo, and Yegua--which have yielded

fossiliferous and calcareous sandstones and clays. The Starr County

sites for Lesquerella thamnophila occur within the Jimenez-Quemado soil

association and on Catarina series soils. Jimenez-Quemado soils are

well-drained, shallow, gravelly to sandy loams underlain by caliche

locations are associated with three Eocene-age geologic

formations--the Jackson, Laredo, and Yegua--which have yielded

fossiliferous and calcareous sandstones and clays. The Starr County

sites for Lesquerella thamnophila occur within the Jimenez-Quemado soil

association and on Catarina series soils. Jimenez-Quemado soils are

well-drained, shallow, gravelly to sandy loams underlain by caliche.

Catarina series soils are clayey, saline upland soils developed from

calcareous, gypsiferous, or saline clays that usually contain many

drainages and erosional features. The underlying material of these

soils contains many calcareous concretions, gypsum crystals, and marine

shell fragments (Thompson, et al. 1972).

The soils of Zapata County have not been mapped in detail, but the

bladderpod sites in Zapata County occur within the Zapata-Maverick soil

association, based upon the general soils map for the county. Zapata

soils are shallow and well-drained, occurring over caliche. Maverick

soils are upland clayey soils occurring over caliche with the

underlying calcareous material also containing shale and gypsum

crystals (Thompson, et al. 1972).

Lesquerella thamnophila occurs as a herbaceous component of an open

Leucophyllum frutescens (cenizo) shrub community that grades into an

Acacia rigidula (blackbrush) shrub community. Both plant communities

dominate many upland habitats on shallow soils near the Rio Grande

(Diamond 1990). Other common plant species in the cenizo and blackbrush

communities include Acacia berlandieri (guajillo), Prosopis glandulosa

(mesquite), Celtis pallida (granjeno), Yucca treculeana (Spanish

dagger), Zizyphus obtusifolia (lotebush), and Porlieria angustifolia

(guayacan). The aggressively invasive nonnative Cenchrus ciliaris

(buffelgrass) is also commonly present. These shrublands are sparsely

vegetated due to the shallow, fast-draining soils and semi-arid climate

(Poole 1989)

andieri (guajillo), Prosopis glandulosa

(mesquite), Celtis pallida (granjeno), Yucca treculeana (Spanish

dagger), Zizyphus obtusifolia (lotebush), and Porlieria angustifolia

(guayacan). The aggressively invasive nonnative Cenchrus ciliaris

(buffelgrass) is also commonly present. These shrublands are sparsely

vegetated due to the shallow, fast-draining soils and semi-arid climate

(Poole 1989).

These open brushland communities are used primarily as rangeland

and, due to the semi-arid environment, are sensitive to soil erosion

and vegetation changes brought about by long-term livestock overgrazing

(Schlesinger, et al. 1990). As a result, root-plowing of shrubs and

subsequent planting of buffelgrass are common regional practices for

rangeland improvement. Cattle reportedly graze on Lesquerella

thamnophila (Poole 1989).

Lesquerella thamnophila occurred historically in Zapata and Starr

counties in the United States. It has never been collected in Mexico

despite its potential occurrence there. Recent surveys of historical

locations in Starr County failed to relocate those populations. Poole

(1989) located three populations, two in Zapata County and one in Starr

County. In April 1994, Bill Carr and Lee Elliott of the Texas Parks and

Wildlife Department discovered another previously unknown Starr County

location (Lee Elliott, pers. comm. 1994).

The number of plants in known populations appears to fluctuate

dramatically in apparent response to precipitation (Poole 1989). In

1985, there were approximately 5,000 plants at one 4-hectare (ha) (10-

acre (ac)) Zapata County site (Tigre Chiquita) and approximately 1,000

plants at the 15-acre type locality in Zapata County (Falcon Lake

West). The year 1986 was dry; only 28 plants were counted at the Tigre

Chiquita site, and none at Falcon Lake West. Plants were seen at both

Zapata County sites again in 1988, but no specific population counts

were recorded. No plants have been observed at the Falcon Lake West

site since 1988

Chiquita) and approximately 1,000

plants at the 15-acre type locality in Zapata County (Falcon Lake

West). The year 1986 was dry; only 28 plants were counted at the Tigre

Chiquita site, and none at Falcon Lake West. Plants were seen at both

Zapata County sites again in 1988, but no specific population counts

were recorded. No plants have been observed at the Falcon Lake West

site since 1988.

The Texas Parks and Wildlife Department has established a

management agreement with the Texas Department of Transportation for

the Tigre Chiquita site. The agreement requires that the transportation

agency avoid mowing within the highway right-of-way from February to

May, while the plant is actively growing. The Texas Parks and Wildlife

Department annually monitors the site for population size and has

recorded these numbers: 10 reproductive plants and 3 non-reproductive

ones in 1991; no plants in 1992; 7 non-reproductive plants in 1993; one

reproductive plant in 1994; 3 non-reproductive plants in 1995; and no

plants in 1996 (probably due to drought).

In 1986, Poole (1989) found 20 plants at a 2-ha (5-ac) site in

Starr County (Santa Margarita Ranch). Plants were again observed at

this site in 1994, but the number of individuals was not recorded that

year (Gena Janssen, Texas Parks and Wildlife Department, Austin, Texas,

pers. comm. 1994). Approximately 70 plants were seen in 1997. In 1994,

the Texas Parks and Wildlife Department recorded about 50 plants at a

new Starr County site (Cuellar Tract) located on a tract of the Lower

Rio Grande National Wildlife Refuge. In 1996, a monitoring plot was

established and a total of 131 plants were located, 84 of them non-

reproductives. In 1997, an extremely wet year, the estimated number of

individuals increased to several thousand, all within a 2-3 acre

section of the tract.

Lesquerella thamnophila is a cryptic annual species and blooms

within a set

on a tract of the Lower

Rio Grande National Wildlife Refuge. In 1996, a monitoring plot was

established and a total of 131 plants were located, 84 of them non-

reproductives. In 1997, an extremely wet year, the estimated number of

individuals increased to several thousand, all within a 2-3 acre

section of the tract.

Lesquerella thamnophila is a cryptic annual species and blooms

within a set

period of time following spring rainfall, creating a short period in

which to survey. These factors may contribute to the occasional

inability to locate these plants at known sites. Additional surveys

carried out at the most favorable times to find specimens, and focusing

on associated soil types, are warranted during the review of this

species for listing as endangered.

Previous Federal Action

Federal action involving this species began with section 12 of the

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

seq.), which directed the Secretary of the Smithsonian Institution to

prepare a report on those plants considered to be endangered,

threatened, or extinct. This report, designated as House Document No.

94-51, was presented to Congress on January 9, 1975. On July 1, 1975,

the Service published a notice in the Federal Register (40 FR 27823)

accepting the Smithsonian report as a petition within the context of

section 4(c)(2) of the Act, now section 4(b)(3)(A), and announcing that

it would initiate a review of the status of those plants. Lesquerella

thamnophila was included as threatened in the Smithsonian report and in

the Service notice.

On June 16, 1976 (41 FR 24523), the Service published a proposed

rule to determine approximately 1,700 vascular plants as endangered.

Lesquerella thamnophila was included in this proposal. However, the

1978 amendments to the Act required the withdrawal of all proposals

over 2 years old (although a 1 year grace period was allowed for those

proposals already over 2 years old)

e Service notice.

On June 16, 1976 (41 FR 24523), the Service published a proposed

rule to determine approximately 1,700 vascular plants as endangered.

Lesquerella thamnophila was included in this proposal. However, the

1978 amendments to the Act required the withdrawal of all proposals

over 2 years old (although a 1 year grace period was allowed for those

proposals already over 2 years old). On December 10, 1979 (44 FR

70796), the Service published a notice withdrawing that portion of the

June 16, 1976, proposal that had not been made final.

On December 15, 1980 (45 FR 82823), the Service published a list of

plants under review for listing as threatened or endangered, in which

Lesquerella thamnophila was included as a category 2 candidate.

Category 2 candidates were those species for which available

information indicated listing as threatened or endangered may have been

appropriate, but for which substantial data were not available to

support preparation of a proposed rule.

Section 4(b)(3)(B) of the Act requires that findings be made by the

Secretary on pending petitions within 12 months of their receipt.

Section 2(b)(1) of the 1982 amendments to the Act required that all

petitions pending as of October 13, 1982, be treated as having been

submitted on that date. The 1975 Smithsonian report was accepted as a

petition; therefore, all the plants noted within the report, including

Lesquerella thamnophila, were treated as being newly petitioned on

October 13, 1982. In each subsequent year, from 1983 to 1993, the

Service determined that the petition to list Lesquerella thamnophila

was warranted, but precluded by other listing actions of higher

priority, and that additional data on vulnerability and threats were

still being compiled.

A status report on Lesquerella thamnophila was completed August 8,

1989 (Poole 1989)

ewly petitioned on

October 13, 1982. In each subsequent year, from 1983 to 1993, the

Service determined that the petition to list Lesquerella thamnophila

was warranted, but precluded by other listing actions of higher

priority, and that additional data on vulnerability and threats were

still being compiled.

A status report on Lesquerella thamnophila was completed August 8,

1989 (Poole 1989). That report provided sufficient information on

biological vulnerability and threats to warrant reassigning the species

as a category 1 candidate and supporting preparation of a proposed rule

to list Lesquerella thamnophila as endangered. ``Category 1

candidates'' were those for which the Service had substantial

information indicating that listing under the Act was warranted.

Notices revising the 1980 list of plants under review for listing

as endangered or threatened were published in the Federal Register on

September 27, 1985 (50 FR 39626), February 21, 1990 (55 FR 6184), and

September 30, 1993 (58 FR 51171). Lesquerella thamnophila was included

in the September 30, 1993 notice as a category 1 candidate.

The 1996 Notice of Review ( 55 FR 6184) included Lesquerella

thamnophila as a candidate. Candidates are species for which the

Service has sufficient information indicating that a listing proposal

is appropriate. The 1997 Notice of Review (62 FR 49398) also included

Lesquerella thamnophila as a candidate.

Summary of Factors Affecting the Species

mber 30, 1993 notice as a category 1 candidate.

The 1996 Notice of Review ( 55 FR 6184) included Lesquerella

thamnophila as a candidate. Candidates are species for which the

Service has sufficient information indicating that a listing proposal

is appropriate. The 1997 Notice of Review (62 FR 49398) also included

Lesquerella thamnophila as a candidate.

Summary of Factors Affecting the Species

Section 4 of the Act and regulations (50 CFR part 424) promulgated

to implement the listing provisions of the Act set forth the procedures

for adding species to the Federal lists. A species may be determined to

be an endangered or threatened species due to one or more of the five

factors described in section 4(a)(1). These factors and their

application to Lesquerella thamnophila are as follows:

A. The present or threatened destruction, modification, or

curtailment of its habitat or range. Habitat destruction and

modification are the primary threats to Lesquerella thamnophila. These

threats include the introduction of non-native pasture grasses such as

buffelgrass and conversion of native rangeland to improved pasture,

overgrazing, urban development, construction or improvement of highways

and utility transmission systems necessary to support urban

infrastructures, and oil and gas exploration and production. These

types of activities have destroyed or altered more than 95 percent of

the native habitat in south Texas (Jahrsdoerfer and Leslie 1988).

It is a common practice in south Texas to improve rangeland for

livestock production by removing the native shrubs through root-plowing

or aerial herbicide application and then reseeding the area with non-

native grasses, usually buffelgrass. This practice potentially destroys

Lesquerella thamnophila habitat. Buffelgrass has spread beyond the

improved pastures and is now present throughout south Texas. This

invasive non-native grass out-competes and displaces native grasses,

forbs, and small shrubs

shrubs through root-plowing

or aerial herbicide application and then reseeding the area with non-

native grasses, usually buffelgrass. This practice potentially destroys

Lesquerella thamnophila habitat. Buffelgrass has spread beyond the

improved pastures and is now present throughout south Texas. This

invasive non-native grass out-competes and displaces native grasses,

forbs, and small shrubs. Potential sites for native plant seedling

establishment are lost due to light and moisture competition with

buffelgrass, and possibly due to allelopathy.

Much of south Texas was severely overgrazed in the past, and

overgrazing continues in many areas today. Vegetation of the semi-arid

south Texas climate is less resilient to the impacts of long-term

grazing than is the vegetation of wetter climates. This has led to

severe erosion of the often highly erodible south Texas soils

(Schlesinger, et al. 1990). It is impossible to calculate how much

habitat suitable to Lesquerella thamnophila may have been lost in the

past because of the destructive effects of overgrazing or the

conversion of native rangeland to improved pasture.

Lesquerella thamnophila is threatened by potential urban

development. The type locality for this species has been reduced to a

small vacant lot in a resort subdivision on Falcon Reservoir in the

City of Zapata. This area is undergoing rapid retirement home

development. Another Lesquerella thamnophila population occurs in an

abandoned trailer park adjacent to a major highway. Recent construction

of convenience stores in the area could stimulate urbanization that

might extirpate the population.

South Texas is undergoing a rapid increase in highway improvements

and construction to handle increased traffic stimulated by the North

American Free Trade Agreement. There are Lesquerella thamnophila

populations adjacent to existing roads that could be proposed for

widening. Additionally, existing unimproved roads adjacent to

populations could be proposed for widening and paving

population.

South Texas is undergoing a rapid increase in highway improvements

and construction to handle increased traffic stimulated by the North

American Free Trade Agreement. There are Lesquerella thamnophila

populations adjacent to existing roads that could be proposed for

widening. Additionally, existing unimproved roads adjacent to

populations could be proposed for widening and paving.

There are Lesquerella thamnophila populations adjacent to

maintained highway rights-of-way where herbicides are used to control

vegetation around

bridges, guard rails, signs, and reflector posts. Herbicides may also

be used to kill woody species encroaching into the rights-of-way and

along fence lines. Any plants within the rights-of-way are threatened

by maintenance practices such as blading or disking and reseeding with

erosion control seed mixtures, which contain primarily non-native

invasive grasses.

South Texas is presently undergoing a significant increase in oil

and gas exploration and production, especially in Zapata and Starr

counties. All phases of exploration and production have the potential

to harm Lesquerella thamnophila populations and habitat. The seismic

vibration method of gas exploration results in extensive temporary

rights-of-way being cleared to facilitate equipment traffic. The

construction of well pads, access roads, electric lines, and oil

gathering lines from wells, if not planned properly, can all destroy

plants and habitat. The proximity of this species to existing oil and

gas development poses a threat from an increase in number and capacity

of gathering lines.

B. Overutilization for commercial, recreational, scientific, or

educational purposes. No commercial trade is currently known to exist

for the species. However, listed plant species can be threatened by

both collection and vandalism, activities difficult to prevent and only

regulated on lands under Federal jurisdiction or in knowing violation

of a State law or regulation

of gathering lines.

B. Overutilization for commercial, recreational, scientific, or

educational purposes. No commercial trade is currently known to exist

for the species. However, listed plant species can be threatened by

both collection and vandalism, activities difficult to prevent and only

regulated on lands under Federal jurisdiction or in knowing violation

of a State law or regulation. Listing a plant species can precipitate

commercial and scientific interest in the species. This interest can

threaten the species through unauthorized and uncontrolled collection.

Federally listing a species under the Act creates the potential for

vandalism at known and potential habitat sites. In many areas, private

landowner concern regarding endangered species is especially high and

may result in the intentional destruction of endangered species

habitat.

C. Disease or predation. The populations of Lesquerella thamnophila

have shown no evidence of disease. However, Poole (1989) reports that

cattle graze the species to the extent that numbers of plants in

populations subjected to grazing are severely reduced compared to those

in adjacent, ungrazed lands. Grazing and browsing are greater threats

during drought conditions when range quality is reduced and other

forage species have been reduced or removed. This portion of south

Texas is sensitive to overgrazing during drought conditions due to the

semi-arid environment and the large area needed per grazing animal,

even under ideal range conditions.

D. The inadequacy of existing regulatory mechanisms. The species is

not currently protected by any Federal or State laws or regulations.

E. Other natural or man-made factors affecting its continued

existence. There are only four known small Lesquerella thamnophila

populations with widely fluctuating numbers of plants from year to

year. Low plant numbers during drought years could cause genetic drift

inadequacy of existing regulatory mechanisms. The species is

not currently protected by any Federal or State laws or regulations.

E. Other natural or man-made factors affecting its continued

existence. There are only four known small Lesquerella thamnophila

populations with widely fluctuating numbers of plants from year to

year. Low plant numbers during drought years could cause genetic drift.

This has the effect of lowering genetic variability and may reduce the

species' ability to cope with environmental perturbations. The reduced

number of plants during drought years, with populations in some areas

actually being reduced to zero above-ground vegetative individuals,

also makes the species vulnerable to extinction from a prolonged

drought. Lesquerella thamnophila occurs along the Rio Grande and the

effect of past flooding on creating or maintaining habitat for the

species is unknown. The extreme rarity of this species makes

populations vulnerable to extirpation and the species vulnerable to

extinction from a variety of random environmental events.

The Service has carefully assessed the best scientific and

commercial information available regarding the past, present, and

future threats faced by the species in determining to propose this

rule. Based on this evaluation, the preferred action is to list

Lesquerella thamnophila as endangered. The endangered status is

appropriate because of the species' limited distribution, low

population numbers, and imminent threats of habitat destruction.

Threatened status would not accurately reflect the current status of

this species.

Critical Habitat

species in determining to propose this

rule. Based on this evaluation, the preferred action is to list

Lesquerella thamnophila as endangered. The endangered status is

appropriate because of the species' limited distribution, low

population numbers, and imminent threats of habitat destruction.

Threatened status would not accurately reflect the current status of

this species.

Critical Habitat

Critical habitat is defined in section 3 of the Act as--(I) the

specific areas within the geographical area occupied by a species, at

the time it is listed in accordance with the Act, on which are found

those physical or biological features (I) essential to the conservation

of the species and (II) that may require special management

considerations or protection and; (ii) specific areas outside the

geographic area occupied by a species at the time it is listed, upon a

determination that such areas are essential for the conservation of the

species. ``Conservation'' means the use of all methods and procedures

needed to bring the species to the point at which listing under the Act

is no longer necessary.

Section 4(a)(3) of the Act, as amended, and implementing

regulations (50 CFR 424.12) require that, to the maximum extent prudent

and determinable, the Secretary designate critical habitat at the time

the species is determined to be endangered or threatened. Service

regulations (50 CFR 424.12(a)(1)), state that designation of critical

habitat is not prudent when one or both of the following situations

exist--(1) the species is threatened by taking or other human activity,

and identification of critical habitat can be expected to increase the

degree of threat to the species, or (2) such designation of critical

habitat would not be beneficial to the species

egulations (50 CFR 424.12(a)(1)), state that designation of critical

habitat is not prudent when one or both of the following situations

exist--(1) the species is threatened by taking or other human activity,

and identification of critical habitat can be expected to increase the

degree of threat to the species, or (2) such designation of critical

habitat would not be beneficial to the species.

As discussed under Factor B in the ``Summary of Factors Affecting

the Species'' section of this rule, Lesquerella thamnophila is

threatened by vandalism, an activity difficult to prevent and only

regulated by the Act with respect to endangered plants in cases of (1)

removal and reduction to possession from lands under Federal

jurisdiction, or their malicious damage or destruction on such lands;

and (2) removal, cutting, digging up, or damaging or destroying in

knowing violation of any State law or regulation, including State

criminal trespass law.

The limited protection for plants on private land renders them

particularly vulnerable to vandalism or collection due to their lack of

evasive ability. Simply listing a plant species can precipitate

commercial and scientific interest, legal as well as illegal, which can

threaten the species through unauthorized and uncontrolled collection

for both commercial and scientific purposes. The designation of

critical habitat involves publication of habitat descriptions and

general mapped locations of the species, greatly increasing the

likelihood of unwanted notice by potential collectors and of successful

search and removal operations at specific sites.

Such information also greatly exacerbates the potential for

vandalism of endangered or threatened plants at known and potential

habitat sites. The designation of critical habitat affects only Federal

projects or activities which they fund, authorize, or carry out

asing the

likelihood of unwanted notice by potential collectors and of successful

search and removal operations at specific sites.

Such information also greatly exacerbates the potential for

vandalism of endangered or threatened plants at known and potential

habitat sites. The designation of critical habitat affects only Federal

projects or activities which they fund, authorize, or carry out. Its

designation does not affect private land activities conducted by State

and local government activities if the activity does not involve

Federal funds or authorization. However, this is not always easily

understood by private landowners whose property boundaries may be

included within a general description of critical habitat for a

specific species. Identification of proposed critical habitat for other

species has resulted in widespread confusion and heightened concern by

the general public. More importantly, such action has resulted in the

unnecessary destruction of endangered species habitat by landowners in

order to avoid the imagined attention of the Service and perceived

prohibitions on private land.

In the case of Lesquerella thamnophila, the Service finds that

designation of critical habitat is not prudent since it is likely to

increase the degree of threat of take of the species. Publication of

critical habitat descriptions and locations would make the species

especially vulnerable to collection and vandalism.

The designation of critical habitat for Lesquerella thamnophila is

also not prudent since it will provide no additional conservation

benefit to the species. The most severe threats to the species include

the overgrazing of native range, and conversion of native rangeland to

improved pasture with nonnative grasses. Designation of critical

habitat will not affect these threats, since impacts stem from private

land activities

tat for Lesquerella thamnophila is

also not prudent since it will provide no additional conservation

benefit to the species. The most severe threats to the species include

the overgrazing of native range, and conversion of native rangeland to

improved pasture with nonnative grasses. Designation of critical

habitat will not affect these threats, since impacts stem from private

land activities. Further protection of habitat on private or State land

will be addressed through the recovery process and will involve

identifying measures that can mutually benefit both the species and

landowner.

Section 7 of the Act requires Federal agencies to ensure that

activities they authorize, fund, or carry out are not likely to

jeopardize the continued existence of a listed species or cause the

destruction or adverse modification of its critical habitat.

Lesquerella thamnophila is currently restricted to four sites ranging

from 5 acres to 45 acres in size. Any adverse impact to sites that

would result in destruction or adverse modification of critical habitat

would likely also jeopardize the continued existence of Lesquerella

thamnophila. Thus, in the case of this species, critical habitat would

provide no additional benefit beyond that provided through listing as

endangered.

In summary, the Service finds that Lesquerella thamnophila is

vulnerable to collection and vandalism, and that identification of

critical habitat would increase its vulnerability. Further, adequate

protection from adverse Federal actions is provided through listing the

species as endangered under the Act, and designation of critical

habitat would provide little additional protection. Therefore, the

Service finds that designation of critical habitat would, on balance,

be detrimental to the species. Critical habitat designation is thus not

prudent.

Available Conservation Measures

equate

protection from adverse Federal actions is provided through listing the

species as endangered under the Act, and designation of critical

habitat would provide little additional protection. Therefore, the

Service finds that designation of critical habitat would, on balance,

be detrimental to the species. Critical habitat designation is thus not

prudent.

Available Conservation Measures

Conservation measures provided to species listed as endangered or

threatened under the Act include recognition, recovery actions,

requirements for Federal protection, and prohibitions against certain

practices. Recognition through listing results in public awareness and

conservation actions by Federal, State, and local agencies, private

organizations, and individuals. The Act provides for possible land

acquisition and cooperation with the States and requires that recovery

actions be carried out for all listed species. The protection required

of Federal agencies and the prohibitions against certain activities

involving listed plants are discussed, in part, below.

Section 7(a) of the Act, as amended, requires Federal agencies 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 being designated. Regulations implementing this

interagency cooperation provision of the Act are codified at 50 CFR

part 402. Section 7(a)(4) requires Federal agencies to confer

informally with the Service on any action that is likely to jeopardize

the continued existence of a species proposed for listing or result in

destruction or adverse modification of proposed critical habitat. For

listed species, 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 the species or destroy or

adversely modify its critical habitat

to jeopardize

the continued existence of a species proposed for listing or result in

destruction or adverse modification of proposed critical habitat. For

listed species, 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 the species or destroy or

adversely modify its critical habitat. If a Federal action may affect a

listed species or its critical habitat, the responsible Federal agency

must enter into consultation with the Service.

Federal agency actions that may require conference and/or

consultation as described in the preceding paragraph include brush

clearing for flood control in arroyos within the jurisdiction of the

International Boundary and Water Commission; technical assistance to

landowners by the Natural Resources Conservation Service (formerly Soil

Conservation Service) for activities funded by the Consolidated Farm

Service Agency (formerly Agricultural Stabilization and Conservation

Service); and rangeland herbicide registration by the Environmental

Protection Agency. The Federal Highway Administration will need to

consider the occurrence of the species in activities such as widening

existing roadways or constructing new highways. The U.S. Department of

Housing and Urban Development will need to consider these species when

water, sewer, and power services are authorized following the

development of unauthorized human settlements.

The Act and its implementing regulations set forth a series of

general prohibitions and exceptions that apply to all endangered

plants. All prohibitions of section 9(a)(2) of the Act, implemented by

50 CFR 17.61, apply

he propagation or

survival of the species. It is anticipated that few trade permits would

ever be sought or issued because this species is not in cultivation nor

common in the wild.

It is the policy of the Service (59 FR 34272) to identify to the

maximum extent practicable at the time a species is listed those

activities that would or would not constitute a violation of section 9

of the Act. The intent of this policy is to increase public awareness

of the effect of the listing on proposed and ongoing activities within

a species' range.

One population of the Lesquerella thamnophila occurs on public land

under the jurisdiction of the Service. Collection, damage or

destruction of this species on Federal lands is prohibited, although in

appropriate cases a Federal endangered species permit may be issued to

allow collection. As noted above, such activities on non-Federal lands

would constitute a violation of section 9 if conducted in knowing

violation of State law or regulation, including State criminal trespass

law.

Normal residential lawn care and maintenance and the clearing of small

areas surrounding a residence, which may be used as a fire break are

not violations of section 9 and will not constitute take. The Service

is not aware of any otherwise lawful activities being conducted or

proposed by the public that will be affected by this listing and result

in a violation of section 9.

Questions regarding whether specific activities will constitute a

violation of section 9 should be directed to the Field Supervisor of

the Service's Corpus Christi Office (see ADDRESSES section). Requests

for copies of the regulations regarding listed plants and inquiries

about prohibitions and permits may be addressed to U.S. Fish and

Wildlife Service, Branch of Endangered Species/Permits, P.O. Box 1306,

Albuquerque, New Mexico 87103 (telephone 505/248-6920; facsimile 505/

248-6922).

Public Comments Solicited

Supervisor of

the Service's Corpus Christi Office (see ADDRESSES section). Requests

for copies of the regulations regarding listed plants and inquiries

about prohibitions and permits may be addressed to U.S. Fish and

Wildlife Service, Branch of Endangered Species/Permits, P.O. Box 1306,

Albuquerque, New Mexico 87103 (telephone 505/248-6920; facsimile 505/

248-6922).

Public Comments Solicited

The Service intends 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) Biological, commercial trade, or other relevant data concerning

any threat (or lack thereof) to this species;

(2) Reasons why any habitat should or should not be determined to

be critical habitat as provided by section 4 of the Act;

(3) Additional information concerning the range, distribution, and

population size of this species;

(4) Current or planned activities in the subject area and their

possible impacts on this species.

Final promulgation of the regulations on this species will take

into consideration the comments and any additional information received

by the Service, and such communications may lead to a final regulation

that differs from this proposal.

The Endangered Species Act provides for a public hearing on this

proposal, if requested. Requests must be received within 45 days of the

date of publication of the proposal. Such requests must be made in

writing and addressed to the Field Supervisor (see ADDRESSES section).

Required Determinations

This rule does not contain collections of information that require

approval by the Office of Management and Budget under 44 U.S.C. 3501 et

seq.

National Environmental Policy Act

ted. Requests must be received within 45 days of the

date of publication of the proposal. Such requests must be made in

writing and addressed to the Field Supervisor (see ADDRESSES section).

Required Determinations

This rule does not contain collections of information that require

approval by the Office of Management and Budget under 44 U.S.C. 3501 et

seq.

National Environmental Policy Act

The Fish and Wildlife Service has determined that Environmental

Assessments and Environmental Impact Statements, as defined under the

authority of the National Environmental Policy Act of 1969, need not be

prepared in connection with regulations adopted pursuant to section

4(a) of the Act. A notice outlining the Service's reasons for this

determination was published in the Federal Register on October 25, 1983

(48 FR 49244).

References Cited

Diamond, D. 1990. Plant Communities of Texas (series level). Texas

Parks and Wildlife Department, Austin, Texas.

Jahrsdoerfer, S.E. and D.M. Leslie, Jr. 1988. Tamaulipan Brushland

of the Lower Rio Grande Valley of South Texas: Description, Human

Impacts, and Management Options. U.S. Fish and Wildlife Service,

Biological Report 88(36). 63 pp.

Poole, J. 1989. Status Report on Lesquerella thamnophila. U.S. Fish

and Wildlife Service, Albuquerque, New Mexico.

Rollins, R.C. and E.A. Shaw. 1973. The Genus Lesquerella. Harvard

University Press, Cambridge, Massachusetts.

Schlesinger, W.H., J.F. Reynolds, G.L. Cunningham, L.F. Huenneke,

W.M. Jarrell, R.A. Virginia and W.G. Whitford. 1990. Biological

Feedbacks in Global Desertification. Science 247:1043-1047.

Thompson, C.M., R.R. Sanders, and D. Williams. 1972. Soil Survey of

Starr County, Texas. U.S. Department of Agriculture, Soil

Conservation Service, Temple, Texas.

Authors

The primary authors of this document are Angela Brooks and Kathy

Nemec (see ADDRESSES section).

List of Subjects in 50 CFR Part 17

Endangered and threatened species, Exports, Imports, Reporting and

recordkeeping requirements, Transportation.

anders, and D. Williams. 1972. Soil Survey of

Starr County, Texas. U.S. Department of Agriculture, Soil

Conservation Service, Temple, Texas.

Authors

The primary authors of this document are Angela Brooks and Kathy

Nemec (see ADDRESSES section).

List of Subjects in 50 CFR Part 17

Endangered and threatened species, Exports, Imports, Reporting and

recordkeeping requirements, Transportation.

Proposed Regulation Promulgation

Accordingly, the Service hereby proposes to amend part 17,

subchapter B of chapter I, title 50 of the Code of Federal Regulations,

as set forth below:

PART 17--[AMENDED]

1. The authority citation for part 17 continues to read as follows:

Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.

4201-4245; Pub. L. 99-625, 100 Stat. 3500, unless otherwise noted.

2. Amend Sec. 17.12(h) by adding the following, in alphabetical

order under FLOWERING PLANTS, to the List of Endangered and Threatened

Plants to read as follows:

Sec. 17.12 Endangered and threatened plants.

* * * * *

(h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------

Species

-------------------------------------------------------- Historic range Family Status When listed Critical Special

Scientific name Common name habitat rules

--------------------------------------------------------------------------------------------------------------------------------------------------------

Flowering Plants

* * * * * * *

Lesquerella thamnophila.......... Zapata bladderpod... U.S.A. (TX)........ Brassicaceae....... E ........... NA NA

* * * * * * *

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Dated: December 30, 1997.

Jamie Rappaport Clark,

Director, Fish and Wildlife Service.

[FR Doc. 98-1518 Filed 1-21-98; 8:45 am]

BILLING CODE 4310-55-P