APPENDIX 11

APPENDIX 11

BIOLOGICAL ASSESSMENT

for

Jack Morrow Hills Coordinated Activity Plan

Rock Springs Field Office

Bureau of Land Management

Rock Springs Field Office

July 1999

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APPENDIX 11

Rock Springs Field Office staff specialists are currently 

preparing the Jack Morrow Hills Coordinated Activity Plan 

which proposes future management on public lands in the 

study area. The project area includes 622,340 acres of mixed 

ownership of which 567,720 acres is BLM surface, BLM 

minerals. Resource activities discussed in the Plan include 

air, soil and water, cultural, fire, hazardous materials, lands 

and realty, livestock grazing, minerals management, off-road 

vehicles, recreation, vegetation, watershed, wild horses, wildlife, and special management areas. 

Recently the U.S. Fish and Wildlife Service (USFWS) 

supplied a list of species to be considered while preparing the 

document. The present list was verified by personnel communication on February 11, 1999. Further communication provided an updated species list in October 1999. Table A11-1 

shows the plant and animal species which occur, may occur, 

or historically were found within the planning area. 

TABLE A11-1 

SPECIES LIST 

USFWS Category Common Name 

Listed Species Black-footed ferret 

Bald eagle 

Whooping crane 

Blowout penstemon 

Ute ladies’-tresses 

Colorado River fish species: 

Bonytail chub 

Colorado pikeminnow 

Humpback chub 

Razorback sucker 

Scientific Name 

Mustela nigripes 

Haliaeetus leucocephalus 

Grus americana 

Penstemon haydenii 

Spiranthes diluvialis 

Gila robusta elegans 

Ptychocheilus lucius 

Gila cypha 

Xyrauchin texanus 

Chadrius montanus 

Lynx canadensis 

Arabis pusilla 

Vulpes velox 

Proposed Species Mountain plover 

Canada lynx 

Candidate Species Small rockcress 

Swift fox 

General management prescriptions for each resource activity are provided in the Green River RMP. Refer to this 

document for specific resource management prescriptions 

under the preferred alternative. 

I. PROJECT DESCRIPTION 

Based on concerns raised by the public and Bureau of Land 

Management (BLM) personnel during preparation of the 

Green River Resource Management Plan (RMP), the Rock 

Springs Field Office area will prepare the Jack Morrow Hills 

Coordinated Activity Plan (JMHCAP). This activity plan will 

provide more specific management direction to prevent or 

address potential conflicts among potential development of 

energy resources, recreational activities and facilities and land 

uses in the activity planning area, grazing, important wildlife 

habitat, and other important resources. The planning area 

encompasses the Steamboat Mountain, Greater Sand Dunes, 

White Mountain Petroglyphs, and Oregon Buttes Areas of 

Critical Environmental Concern (ACECs), a portion of the 

South Pass Historic Landscape, and the Oregon Buttes, Honeycomb Buttes, Greater Sand Dunes, Buffalo Hump, 

Whitehorse Creek, South Pinnacles, and Alkali Draw wilderness study areas (WSAs). Attachment 1 provides a general 

location map. Attachment 2 is a map showing prominent 

surface features. Attachment 3 is a complete list of resource 

issues and the affected acreage. Attachment 4 is a map 

showing the “core” area: Steamboat Mountain ACEC, Greater 

Sand Dunes ACEC, and the overlapping crucial habitat. 

Preparation of the JMHCAP is an integrated activity planning effort to specify the appropriate land and resource uses, 

and level of use for BLM-administered public lands in the 

area. The land use planning decisions for leasing fluid 

minerals in the planning area were not ready for inclusion in 

the Green River RMP. Thus, these decisions were deferred in 

order to be determined in the course of developing the 

JMHCAP. Some Green River RMP decisions for mineral 

location in the area were also deferred to the JMHCAP. Thus, 

the primary objective of this effort will be to make the Green 

River RMP fluid minerals leasing decisions and mineral 

location decisions for the planning area and to determine the 

appropriate levels and timing of leasing and development of 

energy resources, while sustaining other important land uses 

and resources such as big game habitat, recreation, grazing, 

etc. These deferred Green River RMP decisions will result in 

amending the Green River RMP. Other actions resulting from 

this planning effort will include transportation planning and 

designating the roads that can be used in the area, and 

identifying grazing practices and recreational activities and 

facilities. 

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APPENDIX 11

II. CURRENT STATUS AND 

HABITAT USE BY 

THREATENED AND 

ENDANGERED SPECIES 

Six federally listed endangered wildlife species may inhabit or may have inhabited the planning area. Endangered 

species include the black-footed ferret, Ute ladies’-tresses, 

Colorado pikeminnow, humpback chub, razorback sucker, 

and the bonytail chub. 

Surveys have been conducted for the Colorado River 

pikeminnow and humpback chub, but they are now considered extirpated in southwest Wyoming. We will only discuss 

effects caused by water depletion for these species as the Rock 

Springs Field Office area has not been identified as critical 

habitat by the U.S. Fish and Wildlife Service. 

A. Listed Species 

1. Black-Footed Ferret (Mustela nigripes) 

Population Distribution 

Populations of black-footed ferrets (if any) are undetermined in the planning area. Historical documentation exists 

of the presence of ferrets in the planning area as recently as 

1963 when a ferret and kits were commonly seen by several 

persons in the southwest part of Eden Valley. There have been 

other sightings near the planning area as recently as 1983. 

Other areas where ferrets are presumed to have occurred are 

Sublette Flats, Seedskadee National Wildlife Refuge (outside 

the planning area), and the Red Desert. 

Dr. Tim Clark has been one of the primary researchers of 

ferrets and their historical presence in Wyoming until and 

since the 1981 discovery of a colony at Meeteetse, Wyoming. 

His information on historical sightings was used extensively 

in this analysis. Each year ferrets are reported and the BLM 

or the Wyoming Game and Fish Department (WGFD) follows 

up with field surveys and personal interviews. The U.S. Fish 

and Wildlife Service has conducted some surveys and prairie 

dog colony inventories in the field office area since 1981. 

Surveys and inventories of prairie dogs have been conducted 

in the field office since 1975 with nearly 60 percent of the area 

completed. Some of the surveys were contracted by the BLM, 

some were performed by BLM biologists and summer temporaries, and others were done by other agencies. We also 

receive information as a result of surveys required to clear 

land use actions under Section 7 of the Endangered Species 

Act. 

From 1851, when the first ferret was described by Audubon, 

to 1976, 145 sightings of at least 167 animals were evaluated 

as valid sightings or likely so. Of the 145 reports, 93 were 

classified as positive, 37 probable, and 15 possible. The 

diversity and competence of respondents lends credence to 

their sightings; such evidence overwhelmingly indicates that 

ferrets still exist in Wyoming and possibly this planning area. 

Remains of 23 ferrets from museum and private collections 

were located. Of the 145 different sightings reported, 35 or 36 

were of dead animals (10 or 11 killed in coyote traps, two in 

badger traps, one was shot, one a road kill, and one drowned 

in a stock tank). Additional mortality was attributed to 

poisoning for coyotes by several respondents. Young ferrets 

were reported in three instances. 

Habitat Requirements 

Potential areas of ferret habitat can be delineated due to 

their association with prairie dogs and prairie dog colonies 

although their diet may also contain some other small mammals and birds. Based upon archaeological and historical 

evidence, researchers have concluded that the black-footed 

ferret has never been very abundant. Primarily nocturnal, 

ferrets spend much of their time below ground and are rarely 

seen during daylight hours. This behavior is probably one of 

the reasons for so few sightings recorded in this planning area 

and elsewhere. 

Conflicts 

Past animal damage control programs probably have had 

the greatest impact on ferret mortality. 

From the 1920s until the mid-1970s, predator control 

through trapping and poisoning resulted in some black-footed 

ferret mortality (67 percent of positive ferret reports). Secondary poisoning of ferrets is also known to have occurred 

from highly toxic rodenticides (or predicides) used in prairie 

dog eradication programs. Loss of ferret prey and secondary 

poisoning of ferrets must be considered in animal damage 

control plans and activities. 

Varmint hunters seek out prairie dog colonies for target 

shooting. Because few people can distinguish between a 

ferret, a burrowing owl, or a prairie dog peering over the 

prairie dog mound, it is to be expected that some black-footed 

ferrets have been killed accidentally by target shooters. Some 

coyote trapping activities have also resulted in ferret mortality 

during the past. These activities need some measure of 

control, and agencies need to initiate a proactive campaign to 

educate hunters and trappers about ferret identification and 

their habits and avoidance programs. 

Land use activities such as rights-of-ways, energy developments, use permits, urban expansion, mineral extraction, 

and grazing projects can reduce or fragment ferret habitat and 

therefore require inventory and clearances. Habitat losses 

have been minimized through analysis, planning, and coordination. 

Status of the black-footed ferret is unlikely to change over 

the analysis period. Ferret populations are expected to remain 

low despite BLM efforts to minimize activities which could 

impact prairie dog colonies. 

2. Bald Eagle (Haliaeetus leucocephalus) 

Population Distribution 

Bald eagles are classified as partly migratory. Bald eagles 

from the northern states and Canada tend to migrate greater 

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APPENDIX 11

distances than do local eagles. About the second week of 

October, bald eagles begin arriving on the Green River. This 

coincides with the kokanee salmon and brown trout run which 

is probably a primary source of autumn food. By Thanksgiving, bald eagles can be found on the Big Sandy and Little 

Sandy rivers, and in Eden Valley. The bald eagle is a winter 

resident outside the planning area, along the Green River and 

Flaming Gorge Reservoir. 

Habitat Requirements 

This bird is often called the fish eagle and with some 

justification. Its main food item is fish, it nests in association 

with water, and it most often winters where fish are available. 

Additional food items include ducks, coots, rabbits, carrion 

(particularly road kills), and small rodents. Bald eagles are 

found primarily along rivers and inland lakes where their nests 

are usually located in large coniferous or deciduous trees. The 

planning area does not contain any waterways with large trees 

and very limited fisheries. Currently, the only known active 

bald eagle nesting sites in the field office area are on the Green 

River on Seedskadee National Wildlife Refuge and on the 

upper Green River. These locations are both outside of the 

planning area. 

The bald eagle is fully protected by the Endangered Species Act of 1973 (Federal Register 43:6230-6233, February 

14, 1978), the Bald and Golden Eagle Act, the Migratory Bird 

Treaties, and Wyoming Game and Fish Department laws. 

Conflicts 

The accelerated decline in numbers of the species since 

World War II has been attributed to several factors. Both the 

peregrine falcon and the bald eagle have suffered reproductive 

problems due to organochloride pesticide poisoning. Shooting is another significant factor, causing an estimated mortality of 75 percent of the fledglings in some areas. Electrocution, while still a problem, has been reduced through alteration 

and redesign of many power transmission systems. 

Raptors are especially susceptible to accidental poisoning 

through predator control programs. Poison baits set out to 

attract coyotes have caused the loss of at least 17 bald eagles 

in Wyoming during the period 1973-1991. Recent golden 

eagle losses have occurred in Wyoming and the field office as 

a result of unauthorized poison baits placed on public and state 

lands. Bald eagles are also at risk to this type of mortality. 

There appears to be an increase in bald eagles over the past 

20 years. Activities associated with the alternatives should 

have little or no impact in altering the present status of the bald 

eagle. 

3. Whooping Crane (Grus americana) 

As of March 21, 1990, only 13 whooping cranes were 

known to be alive and free-roaming in the Gray’s Lake flock. 

Several of these found their way into the Rock Springs Field 

Office area over the past eight or nine years. In 1986, two 

Colorado State University summer wildlife volunteers working for BLM in the Farson area observed a lone whooping 

crane on several occasions. The USFWS was notified and the 

bird was captured and taken to Grays Lake in an attempt to 

have it mated to another crane. During 1987 and 1988 a pair 

did spend part of the summers in Farson grainfields and 

wetlands. Two observations of whooping crane were made 

along Pacific Creek wetlands in 1991 and 1992. 

Whooping cranes select muskeg, prairie potholes, and 

marshes. Their nest is a flat mound in the marsh usually 

containing two buff, blotched eggs. Food habits are similar to 

the resident sandhill crane (Grus canadensis). Though largely 

vegetarian, they eat some animal food. Insects, snails, frogs, 

mice, lizards, snakes and fish have been recorded in their diet. 

Besides eating seeds of wild plants and grains, they also 

consume herbaceous foliage, underground stems, tubers, and 

roots. 

Conflicts 

The greatest mortality among whooping crane is collision 

with powerlines, cables, and fences along streams, wetlands, 

and marshes. New rights-of-way should also consider the 

impacts to large migrating birds and mitigate accordingly. 

Agricultural grain depredation in the Farson Project area by 

both sandhill cranes and whooping crane pose management 

conflicts which have been resolved by the WGFD paying 

depredation claims to landowners. 

Major facilities and activities which conflict with whooping crane habitat include: powerlines, river cable crossings, 

riparian fences; recreation (off-road vehicles, camping, etc.), 

shooting (sport hunting and poaching), wetlands conversion, 

riparian habitat losses, agriculture and irrigation, water diversions, hazardous wastes, and chemical spills. 

4. Blowout penstemon (Penstemon haydenii) 

Population Distribution 

Blowout penstemon is listed as an Endangered species by 

the U.S. Fish and Wildlife Service under the Endangered 

Species Act. This species, a member of the figwort family, 

occurs in two general areas of the interior western United 

States: in the Sand Hills of central Nebraska and a recently 

discovered location in the sand dune country south of the 

Ferris Mountains in south-central Wyoming. The total population consists of thirteen populations in Nebraska containing 

3,000 - 5,000 individuals (Stubbendick, et al., 1997) and 

approximately 300 to 500 plants in one location of less than 20 

acres in Wyoming. Threats to the species include ORV traffic, 

removal of fire, and leveling of the sand dunes. 

Habitat Requirements 

Blowout penstemon is a perennial herb reaching 1 foot tall 

with one to many stems. It has milky-blue to pale lavender 

flowers that are 1 inch long and found in 6 to 10 whorls. It is 

found in sparsely vegetated, actively shifting sand dunes and 

blow-out depressions. It is commonly found with thickspike 

wheatgrass, lemon scurf-pea, and rubber rabbitbrush. It 

flowers from late June to early July. 

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APPENDIX 11

Conflicts 

In order to gather as much information about this species as 

possible and comply with the provisions of the Endangered 

Species Act and BLM national policy, the Rock Springs BLM 

requires surveys of all suitable areas that could provide habitat 

for these species prior to surface disturbing activities. Blowout penstemon has not been found in southwest Wyoming yet 

but a survey by the Wyoming Natural Diversity Database has 

been scheduled for the summer of 2000. Potential habitat is 

on the sand dune areas in the planning area. 

Mandatory surveys and avoidance of this species would 

prevent adverse effects in the planning area. Consultation 

procedures with the U.S. Fish and Wildlife Service and 

mandated under Section 7 of the Endangered Species Act 

would be required for any project that would involve potential 

or known habitat areas for the blowout penstemon. 

In addition, range condition assessments conducted under 

the Standards for Healthy Rangelands and Guidelines for 

Livestock Grazing Management on BLM-administered lands 

would address this species. 

5. Ute Ladies’-tresses (Spiranthes diluvialis) 

Population Distribution 

The Ute ladies’-tresses is listed as a Threatened species by 

the U.S. Fish and Wildlife Service under the Endangered 

Species Act. This species, a member of the orchid family, is 

known to occur in three general areas of the interior western 

United States: near the base of the eastern slope of the Rocky 

Mountains in southeastern and central Wyoming and northcentral and central Colorado and Montana; in the upper 

Colorado River basin, particularly in the Uinta Basin; and 

along the Wasatch Front and westward in the eastern Great 

Basin, in north-central and western Utah and extreme eastern 

Nevada. The total population is approximately 20,500 individuals. The riparian and wetland habitats required by this 

species have been heavily impacted by urban development, 

stream channelization, water diversions and other watershed 

and stream alterations that reduce the natural dynamics of 

stream system, recreation, and invasion of habitat by exotic 

plant species (USFWS 1995). 

The Ute ladies’-tresses has not been found in southwest 

Wyoming yet, although BLM-authorized searches for the 

species have been performed at several locations along the 

Green River. The closest known location of the Ute ladies’-

tresses to the planning area is on the Green River at Brown’s 

Park, Utah. Potential suitable habitat in the planning area may 

be found on Jack Morrow Creek and its tributaries (Rock 

Cabin Creek); Pacific Creek; the meadows at Crookston 

Ranch (located on Nitch Creek); the Sweetwater River and 

tributaries such as Oregon Slough, Harris Slough, Long Slough 

and Dickie Springs Creek; the sand dune ponds (flockets); and 

the perennial/intermittent streams in the Red Desert area 

(Bush Creek, Bear Creek, Red Creek, and Sand Creek). It is 

likely that this species will be found eventually in southwest 

Wyoming due to the proximity of the other populations and 

the similarity of riparian habitat types. 

Habitat Requirements 

The Ute ladies’-tresses reaches a height of eight to 14 

inches and is marked by an open cluster of several small white 

flowers arranged in a spiral resembling braids—a characteristic accounting for its name. The plant grows along streams, 

rivers, ponds, reservoirs, in bogs, or in wetland, riparian or 

seepage areas. This species has been found associated with 

cottonwood, willow, and prairie grassland communities. It 

generally blooms in late July through August and occasionally 

into September. It has been found in locations between 4,300 

and 7,200 feet in elevation. 

Conflicts 

In order to gather as much information about this species as 

possible and comply with the provisions of the Endangered 

Species Act and BLM national policy, the Rock Springs BLM 

requires surveys of all suitable areas that could provide habitat 

for these species prior to surface disturbing activities. In 

addition, the BLM, private industry, and the Wyoming 

Natural Diversity Database are performing searches for the 

Ute ladies’-tresses along the Green River and some of its 

tributaries during the summer of 1999. 

Mandatory surveys and avoidance of this species would 

prevent adverse affects in the planning area. Consultation 

procedures with the U.S. Fish and Wildlife Service as mandated under Section 7 of the Endangered Species Act would 

be required for any project that would involve potential or 

known habitat areas for the Ute ladies’-tresses. 

In addition, range condition assessments conducted under 

the Standards for Healthy Rangelands and Guidelines for 

Livestock Grazing Management on BLM lands would address this species. 

6. Bonytail Chub (Gila robusta elegans) 

Population Distribution 

This native nongame fish was once abundant throughout 

the Colorado River System, based on reports at the turn of the 

century (Cope 1872; Cope and Yarrow 1875; Kirsch 1889; 

Jordan and Evermann 1896). They were apparently found in 

suitable habitats in the Green River and tributaries all through 

western Wyoming. As early as 1960, bonytail chub were 

reported in decreasing numbers in the Lower Basin. The 

species was common in the Green River within Dinosaur 

National Monument from 1964 to 1966, but less common 

from 1968 to 1971. Presently the most abundant populations 

are in the Grays Canyon of the Green River in Utah. 

Habitat Requirements 

Bonytail chub apparently occupy deep, swift, rock-sand 

areas in main channels of the Green River. Water temperatures in desirable habitat are important in that cold water 

discharges from dams displaces them downstream until water 

temperatures sufficiently increase. Lateral and in-stream 

movement studies of this species indicated they moved very 

little from their release point over a sixty-day period in 

summer. There is some vertical and lateral movement in the 

stream between daylight hours and dark. 

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Conflicts 

Impacts to the bonytail chub are about the same as for the 

other rare Colorado River fishes. Water depletions, water 

diversions, reduced stream flows, and reduced water quality 

affect the potential to bring this species back from the brink of 

extinction. Low numbers of bonytail chub and the absence of 

natural reproduction strongly suggest a trend toward extinction. Actions taken as described in Section IV of this document may slow the rate of water depletions to the Colorado 

River System and to this species habitat. 

7. Colorado Pikeminnow (Ptychocheilus 

lucius) 

Population Distribution 

The Colorado pikeminnow is found in the Colorado River 

drainage. Before construction of Flaming Gorge Dam, this 

fish lived in the Green River of Wyoming. Use of “rotenone” 

in removing undesirable fish species prior to closure of gates 

on Flaming Gorge probably extirpated it from Wyoming’s 

portion of the Green River. A recent discovery of pikeminnow 

near Baggs, Wyoming reestablishes the fish as occurring in 

Wyoming. 

Habitat Requirements 

Colorado pikeminnow are generally found in the large 

rivers of the Colorado system, although they have been found 

in medium-sized tributaries. They are the largest American 

minnow, reaching 80 pounds in the lower Colorado River. 

Young pikeminnow prefer slow backwater areas. Adults use 

a variety of habitats but are specialized for habituating fastmoving, silty, canyon waters. Spawning occurs in summer 

(July, August) at water temperatures of about 20o C. The 

preferred spawning habitat is probably over gravel in riffles. 

The Colorado pikeminnow feeds on crustaceans and small 

insect larvae when young. As pikeminnow become larger 

(over 8 inches (200 mm)), they become piscivorous. Although known from the field office area in the first half of the 

century, alteration of the Green River through changes in flow 

regimes and dam building has apparently eradicated this 

species from southwest Wyoming waters. As suitable habitat 

for this species no longer exists in the Green River of Wyoming, it may never again reoccupy historic habitat. 

Conflicts 

Environmental problems as a result of public and private 

land development and construction activities leading to the 

probable extinction of Colorado River pikeminnow and their 

spawning in the Rock Springs Field Office area include: dam 

construction, river impoundment, diversions/augmentations, 

water pollution, hazardous wastes, chemical spills, irrigation, 

and agriculture. Refer to Section III of this document for the 

discussion of mitigation for Colorado River threatened and 

endangered fish species. 

8. Humpback Chub (Gila cypha) 

This fish is endemic to the Colorado River basin, but found 

only in fairly restricted areas. One of its populations occurred 

in the Green River of Utah and Wyoming, but the species is 

probably extinct since the development of Flaming Gorge 

Dam. It is known to have occurred in the Green River and its 

tributaries after the turn of the century. Specimens of this fish 

were taken on the Black’s Fork and Bitter Creek prior to major 

dam construction in southwest Wyoming. 

Population Distribution 

The humpback chub is generally found in steep gradient 

canyons in deep, swift water with a rocky substrate. Little is 

known about its life history. Humpback chub have been 

observed feeding on the surface, and have also been caught on 

hook and line. Humpback chub spawn in early summer, and 

young prefer quiet backwater areas during their first year of 

life. Adults may reach 10 to 16 inches (250 mm) in length. 

Conflicts 

Conflicts with continued existence of this fish species is the 

same as for the Colorado River pikeminnow and other sensitive fish species. 

9. Razorback Sucker (Xyrauchin texanus) 

Population Distribution 

Originally found as far up the Green River as the present 

location of the City of Green River. In unimpounded waters, 

the razorback is limited to Upper Basin rivers, especially the 

Green, Yampa, and mainstream of the Colorado. The largest 

population, estimated at about 1,000 adults, lives in the Green 

River near Jensen, Utah. This species has not been documented in Wyoming in over 30 years. 

Habitat Requirements 

The fish thrives in torrential river rapids and swift water. 

This fish is one of the largest suckers in North America, 

weighing as much as 12 pounds. They have spawned in 

backwater flooded gravel pits in Colorado and up drainage 

ditches and culverts. The razorback was so common at one 

time before the turn of the century that a commercial fishery 

exploited this species for food. For some unexplained reason, 

populations of this fish have not been documented to successfully spawn in recent years. 

Conflicts 

Elimination of clear, swift whitewater areas in Wyoming’s 

portion of the Green River has removed the potential habitat 

suitable for this species. Competition with non-native fish 

species is also given as a reason for population declines within 

suitable habitat. The razorback hybridizes with other sucker 

species in the Upper Colorado River Basin. Behnke and 

Benson (1980) summarized possible reasons for the decline as 

dams, impoundments, and land and water use practices. 

These human-made features drastically modified natural flows 

and river channel characteristics. They blocked spawning 

migrations and changed temperatures. Channelization, diversions, dams, and water use patterns in the main-stem and 

tributary streams have reduced or nearly eliminated backwa698
APPENDIX 11

ters and off-stream impoundments needed for successful 

spawning. 

B. Proposed Species 

1. Mountain Plover (Charadrius montanus) 

Population Distribution 

The mountain plover is a candidate species (proposed as 

threatened) inhabiting the high dry short-grass plains/prairies 

east of the Rocky Mountains, as well as the sagebrush grasslands throughout Wyoming. It is also known from northern 

Utah and northwestern Colorado. The focus of breeding 

activity appears to be northeastern Colorado. 

Taxonomic changes recently placed this bird with other 

plovers and killdeer. The bird is of bland coloration about the 

size of a killdeer without the striking white marking on the 

head and breast. Mountain plover have been documented 

nesting in the cushion plant communities and windswept 

ridges of planning area (Beauvais and Smith. 1999). These are 

naturally occurring habitat type and are not expected to be 

negatively impacted by the proposed action. 

Habitat Requirements 

Parrish, et al. (1993) noted that mountain plover nests in 

northeastern Wyoming were found in areas of short (< 4 

inches) vegetation on slopes of less than 3 percent. Any short 

grass, short shrub, or cushion plant communities could be 

considered as nesting habitat. In Colorado, the mountain 

plover diet is composed of 99.7 percent arthropods, with 

beetles, grasshoppers, crickets, and ants the most important 

food items (Baldwin 1971). Breeding bird surveys between 

1966 and 1987 show an overall decline in the continental 

population of mountain plovers (U.S. Department of Agriculture, Forest Service, 1994a). Surveys completed in 1991 

indicate that only 4,360 to 5,610 mountain plovers remain on 

the North American continent. 

Conflicts 

Probably the most important reasons for the decline of the 

mountain plover are human impacts and habitat alteration on 

breeding grounds and the degradation in the quality of wintering habitats. Loss of breeding habitat due to cultivation and 

prey base declines resulting from pesticide use are also threats 

to mountain plover survival. Cattle often maintain the open 

blue grama/buffalo grass preferred by mountain plovers so 

livestock grazing may benefit the species to some extent. 

However livestock grazing can also result in a reduction in 

prey species for mountain plovers due to the reduction in 

vegetation. Surveys would help determine breeding and 

nesting areas. Activities would avoid nesting and breeding 

areas during these periods. 

2. Canada Lynx (Lynx canadensis) 

The last known lynx in the field office area was taken by a 

hunter in the 1960s just north of Big Sandy Reservoir (outside 

the planning area). This area is out of its “typical” habitat, 

although the cat probably came from the Wind River Mountains or foothills. Cat tracks are often seen in the Prospect 

Mountains and along the Wind River Mountains but these 

have always identified as cougar or bobcat. Commercial 

timber removal could remove some valuable cover, but size of 

sale blocks and select cutting practices should reduce impacts 

to this species. The planning area has no commercial timber 

areas, only small isolated woodlands. Modest restrictions in 

the way animal damage control is conducted will help reduce 

incidental take of this species. 

Population Distribution 

There is little population information on the lynx in the 

Rock Springs Field Office. Lynx were historically distributed 

throughout the Wyoming Range, Wind River Range, and 

Uinta Mountains. Lynx, like other species, wander out of the 

preferred or typical range and are seen in badland and desert 

habitats where they compete with other similar predators. 

However, outside forested habitats, they are more susceptible 

to predation due to a lack of escape cover. 

Habitat Requirements 

Lynx are generally found in association with snowshoe 

hare populations. The areas mentioned above have some 

small populations of snowshoe hares. When these populations cycle (not necessarily every 7 years as literature suggests), lynx must rely on squirrel, deer mice, partridge, cottontail or road kills. Highways and roadways can lead to vehicle/ 

lynx collisions and impede movement. Primary habitat for 

lynx is Engelmann spruce, subalpine fir, and lodgepole pine at 

the higher elevations, generally 6,500 to 9,800 feet. This 

habitat occurs in only very limited amounts in the planning 

area and there are no known populations of snowshoe hare 

within the planning area. 

Conflicts 

Removal of old growth timber, clearcutting in large blocks, 

juniper chaining, and burning are all detrimental to perpetuating the species. Road intrusion into forested habitats results 

in displacement and often collision with individuals. Forest 

road reclamation and obliteration benefits lynx habitat. Wilderness also benefits lynx habitat. In some areas, timber 

management and fire suppression have affected lynx habitat. 

Conversion or alteration of native vegetation communities in 

and adjacent to lynx habitat would decrease prey populations. 

Pre-commercial thinning likely has a direct negative effect on 

snowshoe hare habitat, at least in the short term. 

Grazing use levels, by livestock or wild ungulates, may 

increase competition for forage resources with lynx prey. By 

changing native plant communities, such as aspen and high 

elevation riparian willow, grazing can degrade snowshoe hare 

habitat. 

Road and trail access and recreational use that results in 

snow compaction allows ingress of coyotes into lynx habitat, 

and increased competition for prey. 

Poison baits, traps, snares, and any type of animal damage 

control which is not specific to a species pose a threat to the 

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lynx. Lynx may be incidentally trapped during the trapping 

seasons for other carnivores, particularly bobcat and wolverine (Squires and Lorean 1999). 

C. Candidate Species 

The BLM is mandated by law and policy to protect and 

manage threatened, endangered, candidate, and sensitive plant 

species and their habitat identified by the U.S. Fish and 

Wildlife Service. BLM is also required to protect and manage 

for sensitive species jointly identified and agreed to with the 

appropriate state agency. Additionally, it is the policy of the 

BLM to provide protection to species of concern, including 

former Candidate 1 and 2 species, so as to prevent probable 

future listing. Former Candidate species are provided the 

same protection as BLM Sensitive species under the BLM 

Manual Section 6840 “Special Status Species Management” 

as guided by Instruction Memorandum No. 97-18. 

1. Small Rockcress (Arabis pusilla) 

Population Distribution 

Small rockcress was listed as a Category 1 Candidate 

species for listing under the Endangered Species Act as either 

Threatened or Endangered. The Nature Conservancy ranks 

this plant as G1S1, extremely vulnerable to extinction globally and extremely vulnerable to extirpation statewide. Small 

rockcress is known from only one location in the southern 

Wind River Range in Fremont County, Wyoming. The single 

known population occurs on about 6 acres of suitable habitat 

near Pine Creek, on public land managed by the BLM outside 

the planning area. 

Habitat Requirements 

Small rockcress is found in crevices and on sparsely 

vegetated, very coarse soil in granite-pegmatite outcrops 

surrounded by sagebrush grassland. Most granite-pegmatite 

outcrops in the South Pass area were surveyed in 1986 by the 

Nature Conservancy-Wyoming Natural Diversity Database 

(Mariott 1988). Other suitable habitats along the Lander 

Cutoff were spot-checked. No other populations were located 

during that survey. More plants were found in the immediate 

area during a later survey conducted for the U.S. Fish and 

Wildlife Service (Dorn 1990). The entire population size is 

estimated at 600 individuals. Motorized recreational activity 

and livestock grazing in the area have been identified as 

threats to the population. The extremely restricted geographic 

range of this species makes it highly vulnerable to extinction. 

A Habitat Management Plan (HMP/EA WY-0480WHAP1) was developed for the protection of the small rockcress 

and its habitat in 1994. Protective management actions that 

have been implemented include designation of its habitat and 

surrounding area part of the Special Status Plant Area of 

Critical Environmental Concern (ACEC); construction of a 

500-acre exclosure around the plants and their habitat; closure 

and rehabilitation of two-track trails through the ACEC, 

annual monitoring of the plant populations, closure within the 

ACEC to motorized vehicles, surface disturbing activities and 

livestock grazing; a No Surface Occupancy designation for 

mineral leasing; and institution of a permanent mineral withdrawal (signed February 4, 1998). This species is also 

included in the Special Status Plant Area of Critical Environmental Concern (ACEC) which closes the habitat to surface 

disturbing activities. 

Conflicts 

Although it is not likely that this species occurs within the 

planning area due to limited habitat, granitic outcrops along 

the Sweetwater River may provide suitable habitat. Searches 

for the small rockcress would be required in suitable habitat 

prior to any surface disturbing activities by authorization of 

the Green River Resource Management Plan/Record of Decision (1997) and the BLM Manual Section 6840. 

2. Swift Fox (Vulpes velox) 

Population Distribution 

The swift fox, a federal candidate species, is a resident of 

the Great Plains from the northern Rocky Mountain foothills 

in southern Canada to western Texas. In Wyoming, this 

species primarily inhabits the eastern Great Plains grasslands 

of the state. A few sightings have been reported in the Rock 

Springs Field Office area. 

Habitat Requirements 

Living up to its name, the swift fox can reach speeds of over 

50 km/hr. This speed allows it to catch its prey and also to 

escape predators such as coyotes, golden eagles, bobcats, and 

wolves. Swift fox dens are burrows located in sandy soil on 

open, bald prairie, along fence rows or in plowed fields and 

often in association with prairie dog towns. The diet of swift 

fox varies seasonally. Hunting primarily at night, they feed on 

a variety of food including: small mammals, birds, reptiles, 

amphibians, and insects. 

Conflicts 

Historically, the major threat to the swift fox has been 

extermination by humans. Trapping, shooting, and poisoning 

as part of predator control programs for coyotes and red fox 

caused the extinction of the Canadian population of this 

species. While it is now illegal to kill swift foxes, some are 

still confused with coyotes and red fox and are killed by 

mistake. 

Current threats to the swift fox include habitat loss, automobile traffic, accidental killings, and conversion of grasslands to agricultural lands. 

Other Special Status Species 

General floristic inventories were conducted in the planning area by botanists from the University of Wyoming Rocky 

Mountain Herbarium and the Wyoming Natural Diversity 

Database between 1994 and 1996. Species specific status 

surveys were performed for Lesquerella macrocarpa (1994) 

and Antennaria arcuata (1994); permanent transects have 

been established and baseline information gathered for these 

species. In addition, the 1995 WNDD vegetation inventory 

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provided information on 10 species of special concern found 

within the planning area. 

III. DIRECT AND INDIRECT 

IMPACTS 

Colorado River Water Depletions (and 

Platte River) 

There are four species of fish in the upper Colorado River 

system that are federally listed as endangered. They are the 

Colorado pikeminnow (Ptychocheilus lucius), the humpback 

chub (Gila cypha), the bonytail chub (Gila elegans) and the 

razorback sucker (Xyrauchen texanus). Though they currently exist only downstream from this planning area, water 

from the Upper Green River basin affects the downstream 

habitat for these fish. Under the Recovery and Implementation Program for Endangered Fish Species in the Upper 

Colorado River Basin (RIP), any water depletions from tributary waters within the Colorado River drainage are considered 

as jeopardizing the continued existence of these fish. Tributary water is defined as water that contributes to instream flow 

habitat. Depletion is defined as water which would contribute 

to the river flow if not intercepted and removed from the 

system. 

The RIP was developed as part of a cooperative effort 

between the states of Colorado, Utah, and Wyoming; the 

Bureau of Reclamation (BOR); U.S. Fish and Wildlife Service (USFWS); private water development interests; and 

various environmental groups. In addition, a cooperative 

agreement was signed by the governors of the states of 

Colorado, Utah, and Wyoming; the Secretary of the Interior; 

and the Administrator of the Western Area Power Administration, Department of Energy, to further implement the RIP. 

The Green River RMP (ROD signed October 1997) covered the discussion on depletions to the Colorado River 

system for the entire Field Office. The biological opinion 

received from USFWS dated July 12, 1994 waived the depletion fee for the Green River RMP because the average annual 

depletions were expected to be less than 100 acre-feet. This 

is based on a previous biological opinion by the USFWS 

which stated that sufficient progress was being made by the 

RIP (July 5,1994). All existing livestock watering facilities 

are covered by the “Programmatic Biological Assessment for 

Minor Water Depletions Associated with Reissuing of BLM 

Grazing Leases in the Platte River Basin” of July 1, 1999. 

The BLM retains discretionary authority over individual 

projects within the area for the purpose of endangered species 

consultation. If the recovery program is unable to implement 

the RIP in a timely manner or make sufficient progress in 

recovery of these endangered species, re-initiation of Section 

7 consultation may be required so that new reasonable and 

prudent alternatives can be developed. 

The depletions caused by the activities within Jack Morrow Hills project area are a subset of the amount described in 

the Green River RMP and are covered by its Biological 

Opinion, dated July 12, 1994. There are 5 “watersheds” 

draining the project area: Jack Morrow, Pacific, Killpecker, 

Sweetwater, and Great Divide Basin. The Pacific, Jack 

Morrow, and Killpecker watersheds are part of the Green 

River Basin and the Sweetwater watershed is part of the Platte 

River drainage. For purposes of comparison or tracking, 

water depletions are anticipated to occur from the drilling of 

gas wells (typical deep wells and coalbed methane wells) and 

potentially from livestock watering pits or ponds. The Reasonable Foreseeable Development (RFD) of the Green River 

RMP predicted that 1,206 oil and gas or coalbed methane 

wells could be drilled in the Field Office area. The JMHCAP 

represents 85 of those. For livestock pits or ponds, the Green 

River RMP estimated about 43 may be created or rebuilt in the 

Field Office area. The JMHCAP represents 23 of those. 

Average annual depletions that are anticipated by these actions could range from 4.9 to 7.4 acre-feet for oil and gas wells 

(standard and coalbed methane) within the Colorado River 

drainage, would be 0.13 acre-feet for oil and gas wells within 

the Platte River drainage, and probably would not exceed 11.5 

acre-feet for livestock ponds (all within the Colorado River 

drainage) after all are installed. 

IV. CUMULATIVE IMPACTS 

The Jack Morrow Hills CAP emphasizes maintenance and 

enhancement of threatened and endangered and special status 

species and biodiversity. The impacts to these species and 

critical habitats will be addressed as each activity plan is 

prepared or revised. The following discussion relates only to 

those activities within the plan which could cumulatively 

impact Threatened, Endangered, or Special Status plants and 

wildlife. 

V. COORDINATION WHICH 

WILL REDUCE ADVERSE 

THREATENED AND 

ENDANGERED IMPACTS 

Much of the resource data for the planning area has been 

entered into the Geographic Information System. New information being collected this summer on mountain plovers will 

also be entered into the GIS system. This data has been and 

will be used to overlay conflicting resource information in 

areas of development and or protection, thereby coordinating 

resource management. The BLM is in the process of summarizing data for GIS input for habitats for other threatened and 

endangered species. These data will soon be available for 

future conflict analysis. 

Inventories and clearances are required for authorized 

BLM activities in areas known or suspected to be essential 

habitat for animals and plants classified as a threatened, 

endangered, or special status species. These studies will be 

done in accordance with BLM and U.S. Fish and Wildlife 

Service guidelines to verify the presence or absence of these 

species. In the event that a listed species is identified, the 

lessee/permittee will be required to modify operational plans 

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to include the protection requirements of the species and its 

habitat (e.g., seasonal use restrictions, occupancy limitations, 

facility design modifications). 

Habitat for threatened, endangered, and sensitive plant and 

animal species would be provided, maintained, or improved 

through vegetative manipulation, mitigation measures, or 

other management actions including habitat protection, acquisition, and easements. 

Site specific activity planning (allotment management 

plans, habitat management plans, etc.) and site specific analysis of individual actions require further site specific analysis 

of effects to all resources including threatened and endangered and candidate species. Inventories will be conducted 

and the data bases kept current. 

Off-road vehicle travel in the planning area would be 

limited to designated roads and trails to reduce adverse environmental damage and reduce conflicts with sensitive and/or 

threatened and endangered species. Some roads and trails 

would be closed and reclaimed as a result of transportation 

planning. Transportation planning would include proper road 

location, construction, reconstruction, design, and reclamation. 

Known locations of candidate plant species communities 

are to be protected and closed to: 1) surface disturbing 

activities that could adversely affect the plants or their habitat; 

2) the location of new mining claims (withdrawals will be 

pursued); 3) mineral material sales; 4) off-road vehicle travel; 

5) geophysical exploration activities; and 6) the use of explosives and blasting. 

Please refer to the Draft Environmental Impact Statement 

of the Green River RMP for additional mitigation and or 

protective measures. 

VI. MAY EFFECT/NO EFFECT 

DETERMINATION 

The Jack Morrow Hills Coordinated Activity Plan is an 

overall plan for management direction of various commodity 

and natural resource programs. 

Analysis of the proposed management prescriptions in the 

Preferred Alternative indicate that the JMHCAP is not likely 

to adversely affect the status of any previously discussed plant 

or wildlife species except for the four listed Colorado River 

fish species. Because of the anticipated water depletions from 

the Colorado River tributaries, these species may be adversely 

affected. 

VII. BIBLIOGRAPHY 

Baxter, G.T. and M. Stromberg 1980. Status Report. Report 

to U.S. Fish and Wildlife Service. Denver, Colorado. 

Behnke, R.J. 1992. Native Trout of North America. American 

Fisheries Society Monograph 6. Bethesda, Maryland. 

Carr, A., et al. 1986. The Black-Footed Ferret. Great Basin 

Naturalist Memoirs, Number 8. Brigham Young University. 

Culwell, D. (WESTECH-Western Technology and Engineering Inc.) 1992. Personal communication with BLM Rock 

Springs District Botanist (In District files) November 4, 1992. 

Dorn, R. 1990. Report on the status of Arabis pusilla, a 

Candidate Threatened Species. Report to U.S. Fish and 

Wildlife Service. Denver, Colorado. 

Dorn, R. 1980. Illustrated Guide to Special Interest Vascular 

Plants of Wyoming. U.S. Fish and Wildlife Service and 

Bureau of Land Management. 

Fertig, W. 1998. “Plant Species of Special Concern of the 

Ross Butte Ecosystem, Sublette County, Wyoming,” Prepared for the Bureau of Land Management by the Wyoming 

Natural Diversity Database, Laramie, Wyoming. 

Marriott, H. 1988. Draft Habitat Management Plan for 

Threatened, Endangered, and Sensitive Plant Species and 

Their Habitats on the Rock Springs District, Bureau of Land 

Management. Wyoming Natural Diversity Database, Rocky 

Mountain Heritage Task Force, The Nature Conservancy. 

Richardson, L.; T.W. Clark; S.C. Forrest; T.M. Campbell III; 

et al. 1985. Proceedings of the Black-Footed Ferret Workshop, Sept. 18-19, 1984. Wyoming Game and Fish Department, Cheyenne, Wyoming. 

Sherrod, S.K. 1978. Diets of North American Falconiformes. 

Raptor Research, Volume 12, 1978. Raptor Research Foundation, Inc. Provo, Utah. 

Squires, J.R. and T. Lorean 1999. “Lynx home range and 

movement in Montana and Wyoming-preliminary results.” 

Chapter 11 IN Draft Report of the Lynx Science Team, 

February 1999. 

U.S. Fish and Wildlife Service 1995. Ute Ladies’-tresses 

Agency Review Draft Recovery Plan. Prepared by the Ute 

Ladies’-tresses Recovery Team for Region 6, USFWS. 

U.S. Fish and Wildlife Service 1999. “Canada lynx conservation assessment and strategy,” Lynx Biology Team, July 18, 

1999. Denver, Colorado. 

USDI, Bureau of Land Management 1996. Green River 

Resource Area Resource Management Plan and Final Environmental Impact Statement. Green River Resource Area, 

Rock Springs District. Washington:Government Printing 

Office. 

USDI, Bureau of Land Management 1997. Record of Decision and Green River Resource Management Plan. Green 

River Resource Area, Rock Springs District. 

Washington:Government Printing Office. 

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