Chapter IV. Existing Environment

Habitat Descriptions

Species Accounts

Table K-2 presents a summary of species addressed in this analysis.

Area of Potential Occurrence: BO = Big Oak Flat, BP = Badger Pass, E = El Portal (includes Merced River gorge), F = Foresta, HG = Hazel Green, SE = South Entrance, T = Tioga Pass Entrance, W = Wawona, Y = Yosemite Valley 2 Special-status species: FE = federally endangered, FT = federally threatened, FD = federally delisted (status to be monitored for at least five years), FSC = federal species of concern, CE = California endangered, CT = California threatened, CSC = California species of special concern, R = California rare, PR = Yosemite park rare

Federal Endangered Species

General Ecology and Distribution. Sierra Nevada bighorn sheep are endemic to the Sierra Nevada. Originally, the Sierra Nevada bighorn sheep occurred throughout the range wherever suitable habitat was found. Between 1850 and 1900, their numbers declined dramatically due to diseases contracted from domestic sheep, overhunting, and competition for forage with domestic sheep. By the 1970s, their populations had dwindled to two remnant herds totaling approximately 300 sheep (Wehausen 1980).

In Yosemite, evidence from skulls and horn sheaths suggest that Sierra Nevada bighorn sheep inhabited the Sierra crest and the Cathedral Range. Population declines followed the pattern seen elsewhere in the Sierra Nevada and, by 1914, they were declared extinct in the park. In 1986, native Sierra Nevada bighorn were reintroduced to the Yosemite region in Lee Vining Canyon, just east of Tioga Pass. The size of the herd has fluctuated between a high of 85 or more animals in 1991 (Chow 1992) to less that 20 today (Wehausen 1980).

Sierra Nevada bighorn sheep spend the summer in the alpine where the absence of tree and shrub cover permits the sheep to more easily detect and avoid predators. In winter, the sheep generally move to lower elevations to escape deep snow, but will occasionally remain at higher elevations in light snow years. Suitable habitat is characterized by high elevation meadows in close proximity to steep, rocky terrain.

Reproductive Biology and Breeding Habitat. Adult bighorn generally segregate by sex throughout most of the year with; ewes, lambs, and subadults remain close to the safety of steep rocky terrain, while rams wander more widely. Rams join the ewes in late fall for breeding (Geist 1971).

Diet and Foraging Habitat. Bighorns are highly selective in their diet, generally choosing the most nutritious forage available. Diet includes grasses, herbs, and shrubs. Bighorn typically forage in or very close to steep rocky terrain where forage is sparse or widely scattered. In late summer of dry years, foraging will often be concentrated around springs and seeps where green vegetation is still available (Moore 1991).

Habitat Status in the Project Area. Tioga Pass is the only project area where Sierra Nevada bighorn sheep can be expected to occur. They have been sighted on Mt. Dana and make regular use of Tioga Peak.

Federal Threatened Species

Wildlife

General Distribution. The bald eagle can be found over most of North America. It breeds or winters throughout most of California. In the relatively mild climate of California, the breeding population of bald eagles is resident year-round in most areas. In fall and winter, migratory bald eagles from northern areas arrive in the state, where they remain until late winter or early spring.

Status. The bald eagle was listed as a federally endangered species in 1978 after habitat loss and pesticide contamination led to widespread population declines. Measures taken in the United States to protect habitat, outlaw DDT and other persistent organochlorine pesticides, and other recovery efforts resulted in a rebound in bald eagle populations. In 1995, the bald eagle was reclassified as a federal threatened species. In 1999, the USFWS proposed to remove the bald eagle from the List of Endangered and Threatened Wildlife in the lower 48 states of the United States, because available data indicated the species has recovered. A final ruling is expected by the end of 2000.

Reproductive Biology and Breeding Habitat. Breeding generally occurs from February to July. One to three eggs are laid in a stick platform nest placed in a tree, 50 to 200 feet off the ground. Young usually fledge by the end of August. Human activity near the nest, especially during egg-laying and incubation, can lead to nest desertion or disruption of breeding (USFWS 1986).

Nesting usually occurs within two miles of lakes, reservoirs, rivers, or large streams that support adequate food resources (USFWS 1986). Most nesting by bald eagles in California occurs from 1,000 to 6,000 feet in elevation, but can occur from sea level up to over 7,000 feet (Jurek 1988). Nest trees in California are most often ponderosa pines in mixed conifer stands. Bald eagles construct up to five nests in a nesting territory and alternate nests in different years.

Diet and Foraging Habitat. The most common prey of bald eagles in the west are fish, waterfowl, rabbits, and various type of carrion (Zeiner et al. 1990). Typically, large bodies of water or rivers with abundant fish, snags and other perches serve as foraging habitat.

Habitat and Status in the Project Area. According to park records, no bald eagles currently nest in Yosemite. There is a nesting pair at Cherry Lake, immediately outside the park. The Cherry Lake pair uses Lake Eleanor inside the park for foraging.

Transient bald eagles are occasionally seen in Yosemite Valley, El Portal, Wawona, and Foresta. Riparian and meadow areas may provide foraging habitat for transient eagles. The absence of anadromous fish runs in the Merced River probably limits its value as bald eagle habitat. Otherwise, the condition of river, riparian, and forest habitats that could be used by bald eagles is relatively intact.

General Distribution. The California red-legged frog is known to occur in 22 counties in California, primarily in central coastal California in Butte and El Dorado Counties. Currently, there are two known sites in the Sierra Nevada where the California red-legged frog is found. These sites are both on private land in proximity to Plumas and El Dorado National Forests (Fellers 1997).

General Distribution. The Valley elderberry longhorn beetle is an insect subspecies endemic to the Central Valley of California. It is found in riparian habitats and associated upland habitats where elderberry (Sambucus spp.), the beetle’s foodplant, grows. The Valley elderberry longhorn beetle is found in California to an elevation of about 3,000 feet, and ranges as far north as the Shasta/Tehama county line (Barr 1991) and as far south as Kern County (Shields 1990). The Valley elderberry longhorn beetle is most commonly found along the margins of rivers and streams in the lower Sacramento River and upper San Joaquin Valley (USFS 1994a), most often in riparian elderberry savannah or moist valley oak woodlands. The Valley elderberry longhorn beetle is more abundant in dense native plant communities with a mature overstory and a mixed understory (Barr 1991). The species has been observed in the Sierra Nevada foothills, particularly in Fresno, Madera, and Placer Counties, as well as the eastern Coast Ranges foothills.

General Distribution. Harlequin ducks are at the extreme southern extent of their range in California. They winter in marine waters along rocky coasts from San Luis Obispo County north, and breed inland along fast-flowing, shallow rivers and streams.

General Distribution. Northern goshawks occur in Alaska, Canada, and the more northern mountains of the western United States. In California, goshawks breed in most mountain areas, where they generally remain through the winter. Some northern goshawks move downslope after breeding, as low as valley foothill hardwood habitats. Preferred habitat is moderately dense coniferous forests broken by meadows and other openings, between 5,000 and 9,000 feet elevation.

General Distribution. The California spotted owl is found throughout the entire Sierra Nevada from the southern Cascades south, and in the central Coast Ranges. Surveys through 1993 estimated approximately 1,600 spotted owl sites (pairs and territorial singles) in the Sierra Nevada (Gould 1993). California spotted owl habitat varies from oak and ponderosa pine forests to lower elevation red fir forests up to 7,600 feet in elevation. Prime habitat occurs between 3,000 and 7,000 feet.

Status. Populations of California spotted owls in the Sierra Nevada have steadily declined, and the subspecies is currently being considered for listing as threatened or endangered by the USFWS. The likely cause of this decline is habitat destruction and fragmentation from logging and development. Currently, the rate of decline of spotted owls in some parts of the Sierra Nevada is 10% per year (Steger 2000b). Comparison of the two most recent studies of spotted owls in Yosemite (Gould and Norton 1993; Steger 2000a) suggests that the population of spotted owls in the park is relatively stable. This is likely because habitats in the park are not subject to the same degradation factors as outside the park.

Reproductive Biology and Breeding Habitat. Breeding occurs from about mid-February to mid- or late-September, at which time the young are largely independent of their parents. Eggs are laid and incubated by the female from early April through mid-May. Nests are usually tree cavities, broken-off trees and snags, abandoned nests of other species, or mistletoe clumps. Trees used for nesting are usually very large. Nesting and roosting habitat of spotted owls is typically dense forest, with a canopy closure of greater than 70%. The presence of black oak in the canopy also enhances habitat quality.

Diet and Foraging Habitat. Spotted owls prey mainly on small mammals, but appear to focus on a few species. In the upper Sierra Nevada (over 4,000 feet), prey in mixed coniferous forests is mainly northern flying squirrels. In mid- to lower-elevation habitats, prey is usually both flying squirrels and dusky-footed woodrats. In foothill habitats, spotted owl prey is almost entirely woodrats.

Spotted owls tend to forage in intermediate to late successional forests with canopy closure greater than 40% and a mixture of tree sizes. Foraging habitat also usually shows signs of decadence and includes snags, old trees, and large downed logs. Flying squirrels also show a preference for mature forests where fungi and lichens may be important foods. Woodrats prefer forests with a brushy understory of shrubs or saplings.

Habitat and Status in the Project Area. Surveys conducted in the summer of 2000 provided the following results on the presence of California spotted owls in the areas that could be affected by the Final Yosemite Valley Plan/SEIS (Steger 2000a; Roberts et al. 1988):

Based upon these data, no spotted owl core nesting or roosting areas would be directly affected by development projects. Proposed project sites at Hazel Green, Badger Pass, South Entrance, Big Oak Flat Entrance, and Yosemite Valley, however, are all apparently within the territories of spotted owls, and the sites are likely used as foraging areas. California spotted owls are habitat specialists, needing canopy closure greater than 70% for nesting and roosting, and greater than 40% for foraging (Verner et al. 1992). Habitat meeting such criteria in project areas should be considered potential spotted owl habitat. Spotted owls may be sporadic breeders, with many pairs nesting when weather and prey conditions are favorable. Single owls or nonreproductive pairs that were found in this survey may, in such years, have nests near where they were found roosting.

General Distribution. The Mount Lyell shrew was originally described from three specimens collected during the original Grinnell surveys (Grinnell and Storer 1924). Two of these specimens were found in the vicinity of Mount Lyell in Yosemite National Park. The third specimen was collected near Williams Butte in Mono County. Two more specimens were collected in 1946 in Mono County. The Mount Lyell shrew was found in moist situations near streams, in grass, or under willows (Grinnell and Storer 1924).

Status. Known only from the five specimens at the Museum of Vertebrate Zoology in Berkeley, California, the Mount Lyell shrew is a vulnerable species because of its apparently very limited distribution.

Reproductive Biology and Breeding Habitat. Litte is known about the reproductive biology and breeding habitat of the Mount Lyell shrew.

Diet and Foraging Habitat. The Mount Lyell shrew probably eats insects and other invertebrates found while foraging on ground, in stumps and logs (Grinnell and Storer 1924).

Habitat and Status in the Project Area. Suitable habitat occurs at Tioga Pass.

General Distribution. The spotted bat is considered to be one of North America’s rarest mammals (Zeiner et al. 1990). It is known from only about 25 sites in California (Pierson and Rainey 1998). The spotted bat is a solitary cliff-dweller, and its distribution is closely linked to the availability of cliff roosting habitat. It is found in a wide variety of habitats, from low desert to coniferous forest (Wildlife Society 1996). It generally roosts on high cliff faces. The spotted bat produces echolocation calls within the range of normal hearing.

Surveys completed between 1992 and 1997 in Yosemite National Park found this species in numerous locations, including Wawona, Crane Flat, Tuolumne Meadows, and especially Yosemite Valley.

Status. The numbers of spotted bats have declined in recent decades, with likely causes including pesticide use and habitat destruction and fragmentation.

Reproductive Biology and Breeding Habitat. Females have one young per year, with birth occurring in June to July.

Diet and Foraging Habitat. The spotted bat feeds on a variety of insects, but predominately moths. In montane habitats, the spotted bat forages over meadows, along forest edges, or in open coniferous woodland. The spotted bat generally forages alone.

Habitat and Status in the Project Area. There is a significant population of spotted bats in Yosemite Valley (Pierson and Rainey 1996). Auditory bat surveys were conducted in 1993 at 24 stations in Yosemite Valley in four habitats: large open meadows, wetlands, forest, and open ponderosa pine forest. Acoustic data indicated the spotted bat was present only in meadow and wetland habitats (Pierson and Rainey 1993). Field surveys have confirmed spotted bats foraging on the north side of El Capitan Meadow, just below El Capitan, Bridalveil Meadow, Leidig Meadow, and Ahwahnee Meadow; the spotted bat was not found in Cook’s Meadow or Stoneman Meadow (Pierson and Rainey 1993). It is likely that spotted bats roost on or near Half Dome and El Capitan; Yosemite Valley had the highest population of spotted bats of any location surveyed in California (Pierson and Rainey 1995). Acoustic data collected in 1994 suggest there is a significant population of spotted bats in the Wawona area (Pierson and Rainey 1995). Based upon these surveys, and the habitat and elevation range of this species, the spotted bat is expected to be present at all potential project sites.

General Distribution. The small-footed myotis bat is a common bat of arid uplands in California. It is found on the west and east sides of the Sierra Nevada, in Great Basin habitats from Modoc to Kern and San Bernardino Counties, and in coastal California south to the Mexican border. It occurs in a wide variety of habitats, primarily in relatively arid, wooded, and brushy uplands near water. The summer and winter ranges appear to coincide, but there are few records from winter. This species is found from sea level to at least 8,800 feet in elevation.

Status. Populations of small-footed myotis bats have apparently declined over recent decades, with likely causes including habitat destruction and fragmentation and the use of pesticides.

Reproductive Biology and Breeding Habitat. The small-footed myotis bat mates in the fall. The young are born from May through June, with a peak in late May. Usually there is a single young, but twins are common. Lactating females were found in June and July. Most young are flying by mid-August. The maximum-recorded longevity is 12 years.

Diet and Foraging Habitat. This species feeds on a variety of small flying insects. Prey includes moths, flies, beetles, and bugs. Foraging flight is slow and maneuverable. The small-footed myotis bat is often seen foraging among trees and over water.

Habitat and Status in the Project Area. The small-footed myotis bat is known to occur in Yosemite Valley, based on historic records and a specimen at the Museum of Vertebrate Zoology in Berkeley, California. The small-footed myotis bat was not captured during five days of mist netting in Yosemite Valley in 1993, though it was captured in Wawona in 1994 (Pierson and Rainey 1993; 1995). This species has the potential to occur in all of the proposed project areas in the park, except Tioga Pass.

General Distribution. The long-eared myotis bat is widespread in California but generally is believed to be uncommon in most of its range. This species has been found in nearly all brush, woodland, and forest habitats from sea level to at least 9,000 feet. This species is highly dependent on oak trees for roosting (Pierson 2000).

Mist-net surveys were conducted in the park in 1994 in Tuolumne Meadows, Pate Valley, and Wawona. The long-eared myotis bat was captured at the Wawona Golf Course and along the South Fork of the Merced River in Wawona (Pierson and Rainey 1995).

Status. Populations of long-eared myotis bats have apparently declined over recent decades, with likely causes including habitat destruction and fragmentation and the use of pesticides.

Reproductive Biology and Breeding Habitat. Mating probably occurs in the fall. The young are born from May to July, with a peak in June. The single yearly litter averages one young. Most young are flying by early August. Nursery colonies of 12 to 30 individuals are found in buildings, crevices, snags, and behind bark.

Diet and Foraging Habitat. The long-eared myotis bat feeds on a variety of arthropods including beetles, moths, flies, and spiders. It consumes more beetles than other myotis species, and there is some evidence that it consumes more beetles when it occupies the same territory as M. auriculus. Insects are caught in flight, gleaned from foliage, or occasionally taken from the ground. Foraging flight is slow and maneuverable. This species is capable of hovering. It forages among trees, over water, and over shrubs, preferring the riparian edge (Pierson 2000). It usually forages less than 40 feet above the ground.

Habitat and Status in the Project Area. Mist-net bat surveys took place in Yosemite Valley in 1993 at Mirror Lake, Cook’s Meadow, El Capitan Meadow, and at Yosemite Creek below Lower Yosemite Fall. The long-eared myotis bat was captured only at the Yosemite Creek site (Pierson and Rainey 1993). It was also captured in Wawona. This species is likely to occur in low numbers throughout most of the project area, except Tioga Pass.

General Distribution. The fringed myotis bat is found throughout much of California and from southern through central Nevada. It is found in a wide range of habitats, from low desert scrub to high elevation coniferous forest. This species is found in the Sierra Nevada in deciduous/mixed conifer habitats to about 6,500 feet in elevation.

Day and night, the fringed myotis bat roosts in mines, caves, trees, and buildings. This species is very sensitive to roost disturbance (Wildlife Society 1996).

Status. Populations of fringed myotis bats have apparently declined over recent decades, with likely causes including habitat destruction and fragmentation and the use of pesticides.

Reproductive Biology and Breeding Habitat. The fringed myotis bat has one young per year, with birth occurring in May to June. Maternity roosts contain adult females and may include several hundred individuals, although most known California roosts are small (fewer than 40 females). Males roost singly or in small groups (Wildlife Society 1996).

Diet and Foraging Habitat. The diet of the fringed myotis bat is primarily beetles, but it includes a variety of other taxa, such as moths (Wildlife Society 1996). It tends to forage over water in river corridors in Yosemite (Pierson 2000).

Habitat and Status in the Project Area. Grinnell and Storer found the fringed myotis bat in 1924 in a location just outside the park boundary. Mist-net bat surveys took place in Yosemite Valley in 1993 at Mirror Lake, Cook’s Meadow, El Capitan Meadow, and at Yosemite Creek below Lower Yosemite Fall (Pierson and Rainey 1993). The fringed myotis bat was captured in Cook’s Meadow and the Yosemite Creek site. It was not found in mist-netting surveys in 1994 in Yosemite Valley (Pierson and Rainey 1995). The fringed myotis bat is likely to occur in the entire project area, with the exception of Tioga Pass.

General Distribution. The long-legged myotis bat is widespread in California, but generally is believed to be uncommon in most of its range. This species has been found in nearly all brush, woodland, and forest habitats from sea level to at least 9,000 feet in elevation. This species is highly dependent on oak trees for roosting (Pierson 2000), though is also uses rock crevices, mines, and buildings.

Reproductive Biology and Breeding Habitat. The long-legged myotis bat has one young per year, with birth occurring in June to July. Maternity colonies number from 200 to 500 individuals (Wildlife Society 1996).

Status. Numbers of long-legged myotis bats have apparently declined over recent decades, with likely causes including habitat destruction and fragmentation and the use of pesticides.

Diet and Foraging Habitat. This species feeds primarily on moths, but also feeds on other taxa, including beetles, flies, and termites. Foraging occurs in open areas, often at tree canopy height.

Habitat and Status in the Project Area. The long-legged myotis bat was not recorded in recent surveys in the park (Pierson and Rainey 1993; 1995), though it is expected. It was found in the Grinell and Storer survey (1924). The bat is expected in all of the project areas, with the exception of Tioga Pass.

General Distribution. This species is found in a wide variety of habitats in the Sierra Nevada below 8,000 feet. It roosts in buildings, trees, mines, caves, or crevices. It also roosts under bridges (Wilderness Society 1996). It is one of the bat species that is most tolerant of human habitation, and one of the few that can survive in a relatively urbanized environment.

Mist-net surveys were conducted in the park in 1994 in Tuolumne Meadows, Pate Valley, and Wawona. The Yuma myotis bat was captured at Pate Valley and along the South Fork of the Merced River in Wawona (Pierson and Rainey 1995).

Status. Populations of Yuma myotis bats have apparently declined over recent decades, with likely causes including habitat destruction and fragmentation and the use of pesticides.

Reproductive Biology and Breeding Habitat. The Yuma myotis bat has one litter per year with an average of one young, with birth occurring in June to July. Maternity colonies can be large (200 to several thousand) and contain only adult females and their young. Males roost singly or in small groups.

Diet and Foraging Habitat. The Yuma myotis bat feeds primarily on emergent aquatic insects (Pierson 2000) and forages directly over the surface of open water and relatively still water such as ponds, or pools in streams and rivers.

Habitat and Status in the Project Area. Mist-net bat surveys took place in Yosemite Valley in 1993 at Mirror Lake, Cook’s Meadow, El Capitan Meadow, and at Yosemite Creek below Yosemite Falls (Pierson and Rainey 1993). The Yuma myotis bat was captured at Mirror Lake, El Capitan Meadow, and the Yosemite Creek site. This species was also found in recent mist-netting surveys in Yosemite Valley and Wawona (Pierson and Rainey 1993; 1995). It is expected in all of the project sites, with the exception of Tioga Pass.

General Distribution. The greater western mastiff bat is found along the west side of the Sierra Nevada, primarily at low to mid-elevations, but has been detected up to 10,000 feet in the summer. It is found in a variety of habitats, from desert scrub and chaparral to montane coniferous forest. Its distribution is tied to the availability of suitable roosting habitat and can sometimes be predicted on the basis of significant rock features, such as large granite formations.

Status. Numbers of greater western mastiff bats have apparently declined over recent decades, with likely causes including habitat destruction and fragmentation and the use of pesticides.

Reproductive Biology and Breeding Habitat. The greater western mastiff bat has one young per year, with birth occurring in June to July. Females form maternity colonies, although males are sometimes present.

Diet and Foraging Habitat. The diet of this species appears to be primarily moths, but also includes beetles and crickets in California. It forages in the open and ranges to high altitudes above ground. Some individuals are known to travel more than 25 miles to reach feeding grounds. It is detected most often over desert washes, grasslands, or meadows, but also feeds above the forest canopy.

Habitat and Status in the Project Area. There is a significant population of greater western mastiff bats in Yosemite Valley, based on mist-netting surveys (Pierson and Rainey 1995). Auditory bat surveys were conducted in 1993 at 24 stations in Yosemite Valley in four habitats: large open meadows, wetlands, forest, and open ponderosa pine forest. Acoustic data indicated the greater western mastiff bat was present in Bridalveil Meadow, El Capitan Meadow, Leidig Meadow, Cook’s Meadow, Ahwahnee Meadow, Stoneman Meadow, Wosky Pond, and wetlands near Happy Isles. It was also detected in a few upland habitats east of El Capitan Meadow and Sentinel Picnic Area. It was not detected at Mirror Lake. Yosemite Valley has the highest population of the greater western mastiff bat in any localities surveyed in California (Pierson and Rainey 1995). It also has been captured in Wawona (Pierson and Rainey 1995). The greater western mastiff bat most likely forages in or near all of the project sites.

General Distribution. The Sierra Nevada snowshoe hare is an uncommon resident of upper elevations in the Sierra Nevada as far south as Mariposa, Mono, and Madera Counties. A search for records at the National Museum (Smithsonian), Museum of Vertebrate Zoology in Berkeley, California, and the Los Angeles County Museum found only two specimens from California, suggesting that Yosemite National Park may be near the southern limit of this species’ range. Yosemite’s faunal database contains records for 18 unconfirmed sightings, all from higher elevations. The hare prefers the edges of forested habitats, heterogeneous habitats, and areas with dense understory, particularly in riparian habitats. It is also found in areas with young firs that have branches drooping to the ground, and in patches of ceanothus and manzanita within or bordering fir or pine forests.

Status. Sierra Nevada snowshoe hares were likely always relatively scarce in Yosemite, since this area is apparently at the southern extreme of their range. However, effects such as logging and fire suppression have likely contributed to the Sierra-wide decline of this species.

Reproductive Biology and Breeding Habitat. The Sierra Nevada snowshoe hare breeds mid-February to June or July. The gestation period is 35 to 37 days. Snowshoe hares have 2 to 3 litters per year. Nests are built with grass, fur, and needles that may line a shallow, bowl-like depression placed under a shrub, log, or in slash.

Diet and Foraging Habitat. The Sierra Nevada snowshoe hare grazes and browses. Summer food primarily consists of grasses, forbs, sedges, and low shrubs. Needles and bark of conifers, and leaves and green twigs of willow and alder are eaten in the winter.

Habitat and Status in the Project Area. Unconfirmed sighting records and information from other locations suggest that forested areas surrounding the Tioga Pass and Badger Pass project areas may provide suitable habitat for this species. Given the elevation range of the snowshoe hare, its occurrence at Hazel Green, Big Oak Flat Entrance, and South Entrance is possible.

General Distribution. The Sierra Nevada mountain beaver is found along the Pacific slope of western North America, from lower British Columbia south to the Sierra Nevada to California (Todd 1990). Mountain beavers are typically associated with moist meadows and riparian zones near small perennial streams and creeks within the montane zone (Todd 1990). Mountain beavers are confined to well-vegetated, moist, cool environments — a function of their poor ability to concentrate urine and low tolerance for temperature extremes (Nungesser and Pfeiffer 1965).

Mountain beaver habitat in Yosemite is found in sandy loam soils that are dominated by one or more of the following woody plants: dogwood (Cornus spp.), labrador tea (Ledum glandulosum), willow (Salix spp.), and alder (Alnus spp.). Common herbaceous plants include cow parsnip (Heracleum lanatum), corn lily (Veratrum californicum), broad-leaved lupine (Lupinus latifolius), fireweed (Epilobium spp.), and various grasses (Todd 1990).

There are an estimated 200 to 550 mountain beaver sites in Yosemite National Park. Given rough estimates of two to 12 adults per site, from 400 to 6,600 adults lived in the park in 1990.

Status. Although Yosemite appears to have a relatively healthy population of mountain beavers, impacts such as logging, grazing, and water diversions in other parts of the Sierra Nevada have apparently caused serious declines in this species.

Reproductive Biology and Breeding Habitat. Mountain beavers breed from December through March. Young are born February though May. The litter size averages two to three young. Females usually do not bear young until their second year. Nest chambers are located from 1 to 4.5 feet below the ground surface (Zeiner et al. 1990).

Diet and Foraging Habitat. Mountain beavers feed on vegetative parts of plants including thimbleberry, salmonberry, blackberry, dogwood, salal, ferns, lupines, willow, and grasses. They forage underground, above ground, under snow, on the surface of snow, and up to 15 feet high in trees and bushes. Vegetation is stored near a burrow entrance or in underground chambers (Maser et al. 1981). Mountain beavers in the Sierra Nevada require abundant riparian plants for harvesting, but species composition is relatively unimportant (Todd 1990).

Habitat and Status in the Project Area. Mountain beavers are known to occur in the streams that drain from the meadows and ski slopes at Badger Pass (Monroe Meadow). No suitable habitat occurs in or near the other proposed project areas.

General Distribution. In the Sierra Nevada, the Sierra Nevada red fox prefers forests interspersed with meadows and alpine fell-fields. It is found from 3, 900 to 11,900 feet in elevation, although most sightings and records are from above 7,000 feet in elevation. The Museum of Vertebrate Zoology in Berkeley, California has 12 specimens collected from the immediate vicinity of Tioga Pass. The Museum of Vertebrate Zoology also has two specimens collected from Big Meadow, near Foresta. Open areas are used for hunting, and forested habitats are used for cover and reproduction. Today, this species is exceedingly rare, although a photograph was taken of a red fox at Tioga Pass Resort in January 1991. It could not be determined whether this individual belonged to the native subspecies or was an introduced eastern red fox.

Status. The Sierra Nevada red fox was, at one time, common to uncommon in suitable habitat. Near the turn of the 19th century, wide-scale trapping greatly reduced numbers of Sierra Nevada red foxes. Since then, activities such as logging, grazing, and fire suppression have likely affected the ability of this species to recover.

Reproductive Biology and Breeding Habitat. Breeding takes place in late winter (January-March). After a gestation period of 52 days, young are born in early spring (March-May). Den sites include rock outcrops, hollow logs and stumps, and burrows in deep, loose soil.

Diet and Foraging Habitat. The Sierra Nevada red fox hunts small and medium-sized mammals, ground squirrels, gophers, mice, marmots, woodrats, pikas, and rabbits. It hunts in meadows, fell-fields, grassland, and other open habitats.

Habitat and Status in the Project Area. There is extensive suitable habitat in the Tioga Pass project area. Based on historic occurrence in the Big Meadow area, suitable habitat also exists in all other project areas, except El Portal.

General Distribution. The California wolverine is exceedingly rare, with its distribution scattered over large areas. Optimal habitat for the wolverine is in large tree stages with moderate to dense canopy cover, in red fir, lodgepole pine forests, and in alpine meadows. Special habitat requirements are low human disturbance, and rocky areas, caves, logs, or snags as den sites. Specimens in the Museum of Vertebrate Zoology in Berkeley, California collection originate from Saddlebag Lake and the head of Lyell Canyon. The Yosemite Field Museum has two specimens from Chiquito Lakes. All specimens were collected above 8,000 feet in elevation.

Status. Wolverines were apparently always scarce in the Sierra Nevada, but logging and recreational use of potential habitats have likely further reduced their abundance.

Reproductive Biology and Breeding Habitat. The wolverine mates in summer, with delayed implantation. It bears one to four young the next spring. The wolverine has one litter per year. It excavates burrows under shelving rock or in logs, caves, or snags.

Diet and Foraging Habitat. The wolverine is a solitary hunter and forages on the ground, in trees, burrows, and rock piles for carrion or live prey. It captures prey by digging animals out of their burrows, by pursuit and capture, or by ambush. Prey includes marmots, gophers, squirrels, rats, mice, birds, insects, and occasionally ungulates. The wolverine also eats fruits.

Habitat and Status in the Project Area. Based on the collection of specimens from nearby localities, Tioga Pass lies within the historical range of optimal wolverine habitat.

General Distribution. The American marten is an uncommon to common resident of the Sierra Nevada. Its optimal habitats are various mixed evergreen forests that have more than 40% crown closure and large trees and snags. Important habitats include red fir, lodgepole pine, subalpine conifer, Jeffrey pine, and eastside pine (Grinnell et al. 1937;Schempf and White 1977;USFS 1994b). A survey for forest carnivores in Yosemite generally found martens inhabiting elevations above 7,600 feet in lodgepole pine forest, subalpine meadow/forest edges, and rocky areas (Chow 2000).

Status. Numbers of martens in the Sierra Nevada have been reduced by human influences such as logging and fire suppression.

Reproductive Biology and Breeding Habitat. The American marten breeds in summer and has a gestation period of 220 to 290 days, including delayed implantation. Embryos are generally implanted in uterus in February and have an active growing period of about 37 days prior to birth. Most litters are born in March and April, and some as late as June. Females have one litter per year, with an average of 3.5 young. The young stay with females until autumn and then begin a solitary life. Dens are located in cavities in trees, snags, logs, and rock piles. Dens are usually lined with leaves, grass, mosses, or other vegetation.

Diet and Foraging Habitat. Martens are mostly carnivorous, taking primarily small mammals such as tree squirrels, chipmunks, mice, shrews, rabbits, hares, and pikas. In spring through autumn, martens often eat birds, insects, and fruits. Studies over two winters in Yosemite showed substantial differences in diet between the two winters. White-tailed jackrabbits were the principal food items in 1976/1977 (Hargis and McCullough 1984). Voles were the principal food item in 1979/1980 (Hargis and McCullough 1984).

Martens will eat fish and will forage along the edge of water. They may tunnel under snow. Martens may use their forepaws to remove birds from tree cavities. Individuals may travel up to 16 miles while hunting in one night. They forage on the ground as well as in trees, snags, logs, and rocky areas. During winter, wind-thrown trees and log piles are important as entrances into space under snow for hunting.

Habitat and Status in the Project Area. The Museum of Vertebrate Zoology in Berkeley, California has records for 19 specimens collected in or near Yosemite National Park. Six of these were collected in the Tioga Pass area. Grinnell and Storer (1937) indicated that the densest marten populations in the southern Sierra Nevada were in the Tioga Pass — Mono Lake area. Martens are also potentially found at Badger Pass, Hazel Green, the Big Oak Flat Entrance Station, the South Entrance Station, and rarely in Yosemite Valley.

General Ecology and Distribution. The Pacific fisher is most often found between elevations of 4,000 to 7,000 feet in the Sierra Nevada. Its preferred habitat is mixed-conifer montane hardwood forest with large-diameter trees and a moderate to dense canopy cover. They are also associated with mixed hardwood/conifer forest between 4,000 and 6,000 feet in elevation. Records at the Museum of Vertebrate Zoology in Berkeley, California for specimens collected in Yosemite indicate that fishers were most commonly found between 6,000 and 7,000 feet in elevation. In recent years, the majority of reported fisher sightings and vehicle-related accidents (road kills) have occurred along the Wawona and Big Oak Flat Roads near Henness Ridge and Crane Flat.

Status. Trapping in the Sierra Nevada near the end of the 19th century severely reduced numbers of fishers. Activities such as logging and fire suppression since then have likely inhibited the recovery of this species. Road kills are the single largest cause of unnatural adult fisher mortality.

Reproductive Biology and Breeding Habitat. Breeding generally occurs in mid- to late spring. Gestation, including delayed implantation, is approximately 327 to 358 days, with the period of active pregnancy following implantation and lasting approximately 30 to 60 days. Young are born in early to mid-spring. Natal dens typically consist of cavities found in large-diameter trees or snags.

Diet and Foraging Habitat. Fishers are largely carnivorous. Fishers eat rabbits and hares, especially snowshoe hares and rodents (mice, porcupines, squirrels, mountain beavers), shrews, birds, fruits, and carrion. They opportunistically forage on the ground surface and in trees.

Habitat and Status in the Project Area. Preferred fisher habitat, as evidenced by the locations of historic records and recent fisher sightings, occurs within all of the proposed project areas, except Tioga Pass and El Portal.

General Distribution. The limestone salamander is found in a highly restricted range outside Yosemite National Park near Briceberg, Mariposa County. This area is protected by the 120-acre Limestone Salamander Ecological Reserve and the Bureau of Land Management’s 1,600-acre Limestone Salamander Area of Critical Environmental Concern. The limestone salamander is found in limestone substrates in mixed chaparral habitats along the Merced River and its tributaries from 1,100 to 2,500 feet in elevation (Zeiner et al. 1988). It frequents limestone cliffs and ledges and in talus, especially where overgrown with moss. During periods of surface activity (November to the end of March), this species is uncommon to common on steep north- and east-facing slopes. California buckeye may be an indicator species for optimal habitat.

Status. The limestone salamander is considered vulnerable because of its highly restricted range.

Reproductive Biology and Breeding Habitat. Little is known about habitat requirements for breeding and egg laying for this salamander. A related salamander, H. shastae, apparently breeds and is known to lay eggs in limestone caverns.

Diet and Foraging Habitat. The limestone salamander most likely forages on insects and other small invertebrates.

Habitat and Status in the Project Area. The limestone salamander has never been collected in the park. Its closest occurrence is about 30 miles west of El Portal near Briceburg. The Museum of Vertebrate Zoology in Berkeley, California has an extensive collection of specimens originating from the vicinity of Briceburg on the Merced River. Although the project area in El Portal lies within the elevation range of this species, and suitable vegetative habitat appears to exist, the species is not expected due to a lack of limestone substrate.

General Distribution. The Mount Lyell salamander is found in wet habitats in the Sierra above 4,000 feet. It is typically found under large granite slabs and boulders at the edge of talus slopes (Stebbins 1985). Typical habitat includes rock fissures and seeps from streams or melting snow, shade, and low-growing plants. It has been found near cliffs, cave openings, melting snowbanks, and in the spray zone of waterfalls. Winter hibernation probably occurs within deep rock fissures or under slabs of exfoliating granite.

Status. Mount Lyell salamanders are considered a vulnerable species because of their hightly restricted range.

Reproductive Biology and Breeding Habitat. Little is known about specific microhabitat requirements of breeding and egg laying. Eggs probably are deposited beneath granite rocks or slabs covering moist granite soil.

Diet and Foraging Habitat. Centipedes, spiders, termites, beetles, and adult and larval flies are important food items (Stebbins 1972). Food is obtained under surface objects or while foraging on the surface at night.

Habitat and Status in the Project Area. The Museum of Vertebrate Zoology in Berkeley, California has records for nine specimens taken from Yosemite Valley in the vicinity of Vernal Fall and Curry Village, six specimens from the top of Vernal Fall, 30 from the top of Half Dome, and 18 specimens from various parts of Lyell Canyon. There is suitable habitat for the Mount Lyell salamander in Yosemite Valley, Tioga Pass, and Badger Pass.

General Distribution. The Yosemite toad frequents high mountain meadows and forest borders, emerging soon after the winter snowpack melts. It is found in the central Sierra Nevada at elevations from 6,400 feet to 11,300 feet.

Status. The Yosemite toad has undergone significant population declines in recent years (Fellers and Drost 1993). The cause for the decline of Yosemite toads remains uncertain and does not appear to be strongly linked to either habitat degradation or non-native fish (Drost and Fellers 1994).

Reproductive Biology and Breeding Habitat. Breeding occurs in shallow pools and lake margins, or in quiet water of streams. Egg laying occurs from mid-April to mid-July, depending on local conditions. Eggs are deposited in shallow, quiet pools in wet meadows or in shallow tarns surrounded by forest. Breeding sites are frequently slow-flowing runoff streams with short emergent sedges.

Diet and Foraging Habitat. The diet of this toad includes beetles, ants, mosquitoes, and spiders (Grinnell and Storer 1924; Mullally 1953). Tadpoles feed on bottom detritus or by filtering suspended plant material and planktonic animals.

Habitat and Status in the Project Area. In 1992, Drost and Fellers resurveyed a transect of the Sierra Nevada mountains that has been surveyed for the Yosemite toad in the early 1900s (Grinnell and Storer 1924). The Grinnell and Storer survey discovered the Yosemite toad and described it as a new species. Drost and Fellers found the Yosemite toad at just over half of the 13 sites where it was found by Grinnell and Storer, and in low numbers at most sites (Drost and Fellers 1994).

In 1997, a survey of over 260 sites in Yosemite found the Yosemite toad at a total of only five sites (Fellers and Freel 1995; Fellers 1997). During 1999, the Yosemite toad was found at 14 out of 291 sites that were surveyed. The number of sites with toads and the number of toads at each site were slightly higher than in recent years and may be indicative of a modest recovery, although it is too early to be certain (Fellers and Freel 1995, Fellers 1999).

Records from the Museum of Vertebrate Zoology in Berkeley, California show that juvenile toads and tadpoles were collected from Ahwahnee Meadow in Yosemite Valley in 1956. The collection also contains more than 150 specimens from the immediate vicinity of the Tioga Pass Entrance Station, suggesting that this species was once abundant in the area.

Sherman and Morton (1984;1993) documented changes in the breeding population of Yosemite toads at Tioga Pass. Their yearly surveys from 1971 to 1982 show a nine-fold decrease in marked males and a drop in the average number of toads. In 1992, Drost and Fellers surveyed the Tioga Pass area. No adults were found, and tadpoles were found in only two small ponds near Tioga Lake, despite an abundance of good habitat in the area (Drost and Fellers 1994).

The areas of likely occurrence of Yosemite toads in project sites, based upon previous observations and collections, are meadows and lakes near Tioga Pass. Assuming the identification of the toads and tadpoles obtained 45 years ago in the one collection from Yosemite Valley 45 years ago is correct, this area could be habitat for Yosemite toads; however, the lack of subsequent observations from this area, and the fact that the Valley is far below the usual elevation range of this species, indicate that Yosemite Valley is an unlikely site for a sustainable population of Yosemite toads.

General Distribution. The foothill yellow-legged frog is found from western Oregon to southern California (Behler and King 1979). It was formerly abundant up to 6,000 feet in elevation in the Sierra Nevada, though it has virtually disappeared from its range from uncertain causes.

Remaining foothill yellow-legged frogs live in or near permanent freshwater rocky streams and rivers in a variety of habitats, including valley-foothill hardwood and conifer, chaparral, and wet meadow types (Zeiner et al. 1988). The yellow-legged frog prefers shallow, partially shaded streams with rocky substrates that are at least cobble-sized, with water less than 2 feet deep and fast-flowing water with riffles (Hayes and Jennings 1988). Streams with at least 40% riffles and at least 40% cobble-sized or greater substrates may best suit this species (Hayes and Jennings 1988).

Status. The mountain yellow-legged frog was formerly one of the most abundant amphibian species in California, but is now virtually extinct from its former range. Causes of this extreme decline are unknown at this point, but could include introduction of non-native amphibian (bullfrog) and fish species, pesticides, and disease. Recent data also suggest that fungal infections may be an important factor.

Reproductive Biology and Breeding Habitat. Breeding usually occurs during a two-week period after spring flooding between March and May. Clusters of 100 to 1,000 eggs are attached to gravel or rocks in moving water near stream edges (Zeiner et al. 1988). Tadpoles transform in three to four months (Zeiner et al. 1988).

Diet and Foraging Habitat. Adults feed on both aquatic and terrestrial invertebrates, favoring adult insects. Tadpoles probably graze on algae and diatoms along rocky stream bottoms (Zeiner et al. 1988).

Habitat and Status in the Project Area. Recent surveys found no foothill yellow-legged frogs in Yosemite National Park (Fellers and Freel 1995; Fellers 1997). Suitable habitat for this species occurs in Yosemite Valley, Foresta, Wawona, and El Portal.

General Distribution. The mountain yellow-legged frog is found in the Sierra Nevada, in the extreme western part of Nevada, and in portions of southern California (Behler and King 1979). In the Sierra Nevada it is found in streams, rivers, ponds, and lakes from 4,500 feet to over 12,000 feet in elevation (Jennings and Hayes 1994).

Mountain yellow-legged frogs are seldom found far from water. They occur in montane riparian, lodgepole pine, subalpine conifer, and wet meadow habitats (Zeiner et al. 1988). In the Sierra Nevada, this species is most abundant in lakes formed in glaciated terrain. It is rare or absent in high-elevation lakes where introduced trout have been established (Zweifel 1968). The mountain yellow-legged frog prefers well-illuminated, sloping banks of meadow streams, riverbanks, isolated pools, and lake borders with vegetation that is continuous to the water’s edge (Zeiner et al. 1988). They are especially abundant along lakes and low-gradient streams with irregular shorelines and plentiful rocks (Mullally and Cunningham 1956).

Status. Mountain yellow-legged frogs were once one of the most abundant amphibians at elevations above 6,000 feet in the Sierra Nevada. As surveyed by Drost and Fellers (1994), this frog has undergone significant declines and is now increasingly rare. Lack of frogs probably relates to a number of factors, including the presence of introduced trout and possible airborne contaminants that blow into the Sierra Nevada from the Central Valley (Fellers 1997).

Reproductive Biology and Breeding Habitat. Breeding in the Sierra Nevada usually occurs from June to August when lakes and streams are free from ice. Clusters of 100 to 500 eggs are attached to gravel or submerged rocks in shallow water (Zeiner et al. 1988). Tadpoles usually overwinter and may require two winters to complete their development (Zeiner et al. 1988).

Diet and Foraging Habitat. Mountain yellow-legged frogs feed primarily on aquatic and terrestrial invertebrates and favor terrestrial insects (Zeiner et al. 1988). Tadpoles graze on algae and diatoms along rocky bottoms in shallow water (Zeiner et al. 1988).

Habitat and Status in the Project Area. Though not found in the project area, recent surveys found the mountain yellow-legged frog in 43 sites in Yosemite (Fellers and Freel 1995; Fellers 1997). Suitable habitat is found at or near Badger Pass and Tioga Pass.

[Note: Yosemite is in a zone of intergradation between these two subspecies, where interbreeding makes them indistinguishable. They will, therefore, be addressed here as a single species.]

General Distribution. The western pond turtle is found in the Sierra Nevada up to 6,000 feet in elevation. It is found in permanent ponds, rivers, streams, and irrigation ditches that typically have rocky or muddy bottoms and are overgrown with vegetation. Basking areas are required by this species and include partially submerged logs, rocks, mats of vegetation, or open mud banks.

Status. This species has decreased by up to 80% in numbers, probably due to habitat alternation and non-native predators.

Diet and Foraging Habitat. The diet of the western pond turtle includes small fish, frogs, various aquatic insects, and some plants. Insects probably make up the greatest part of the pond turtle diet, particularly the larvae and nymphs of caddisflies and dragonflies.

Reproductive Biology and Breeding Habitat. The western pond turtle depends on upland habitats in which individuals can over-winter, construct nest chambers, and lay eggs. Most nest chambers are excavated in compacted soils on south-facing slopes that have grassland or scrub vegetation. Eggs are laid between May and July. (VOLPE 1997).

Habitat and Status in the Project Area. Park records show sightings of the western pond turtle in Yosemite Valley and El Portal. Suitable habitat for this species occurs in Yosemite Valley, El Portal, and Wawona.

General Distribution. The Merced Canyon shoulderband snail lives in stable rock slides where there is tree or shrub cover.

Status. This species is vulnerable due to its apparent limited distribution in the Merced River canyon.

Reproductive Biology, Breeding Habitat, and Diet. Little is known about the reproduction and diet of the Merced Canyon shoulderband snail. It likely deposits its eggs in moist locations.

Habitat and Status in the Project Area. The California Academy of Sciences has records for seven specimens collected in the Merced River canyon between 1923 and 1932. These specimens were collected from 0.5 mile west of El Portal to 5.3 miles west of El Portal in rockslide areas (Roth 1972). No specimens have been collected in potential project sites in El Portal, and the habitat at these sites does not appear suitable for this species. The proximity of historic collections of this species, however, requires evaluation of potential impacts at project sites.

This species is also known as Yosemite Mariposa sideband snail (formerly Monadenia hillebrandi yosemitensis).

General Distribution. The Mariposa sideband snail is a narrowly distributed land snail known from the Glacier Point, Curry Village, and Vernal Fall area of Yosemite, and the Merced River canyon west of El Portal (Pilsbry 1939). This snail lives in mossy rockslides with a cover of trees or shrubs (Roth 1972). It prefers stable rather than active rockslides, and rock piles with open crevices rather than those filled with silt. Roth’s 1987 examination of the type specimen (Monadenia hillebrandi yosemitensis) revealed that the type specimen is really another species, M. mormonum (VOLPE 1997). As a result, the scientific name was changed.

Status. This species is vulnerable due to its apparent limited distribution in the Merced River canyon.

Reproductive Biology, Breeding Habitat, and Diet. Little is known about the reproduction and diet of the Mariposa sideband snail. It likely deposits its eggs in moist locations in its habitats.

Habitat and Status in the Project Area. Roth (1972) reports this species as inhabiting rockslides near Vernal Fall and Curry Village. The California Academy of Sciences has records for five specimens collected in the vicinity of Vernal Fall and the Mist Trail from prior to the period 1916 — 1932. Suitable habitat for the Mariposa sideband snail is found in Yosemite Valley and El Portal.

General Distribution. Pygmy grasshoppers are often found in riparian areas, particularly in the spring and early summer. They are generally small (less than 2 inches) with vestigial wings. This species has been found in only a few areas: in the vicinity of El Portal (Rehn and Grant 1956); and in the Sugar Pine area of Madera County at an elevation of 4,300 to 5,000 feet (VOLPE 1997).

Status. The apparent limited distribution of this species makes it vulnerable.

Reproductive Biology, Breeding Habitat, and Diet. Little is known of the breeding habitat of this species or its diet, but it likely lays its eggs in the moist soil of its habitat.

Habitat and Status in the Project Area. Suitable habitat is found in El Portal, Yosemite Valley, Wawona, and at the South Entrance.

General Distribution. The Wawona riffle beetle occurs in rapid streams of California from 2,000 to 5,000 feet in elevation and is considered rare (Usingner 1956). The Wawona riffle beetle was previously known only from a few locations in California (Chandler 1954; Brown 1972), until more recently when it was found in several widely scattered locations in northern California, as well as southern Oregon and Idaho (Shepard and Barr 1991).

The beetle is small, measuring less than 1 inch. Both the larvae and adult life stages are aquatic, but neither life stage actually swims. Rather, both life stages move by crawling on underwater plants and debris. Adults and larvae are found together, usually in cool, small to medium-sized mountain streams and rivers. They are most abundant in aquatic mosses. Many taxa in this family (Elmidae riffle beetles) are typically found clinging to stones or beneath rocks in cold, fast-running water. They are rarely found in streams with seasonal variations in flow, heavy sediments, muddy or sandy bottoms, or low oxygen content (VOLPE 1997).

Status. The Wawona riffle beetle is limited in distribution and difficult to collect for assessment of its distribution and abundance, but appears to be rare where it does occur.

Reproductive Biology, Breeding Habitat, and Diet. Members of this family deposit eggs singly or in small groups on submerged rocks, organic debris, and vegetation. Larvae go through six to eight instars and may take three or more years to mature. They construct terrestrial pupal chambers in moist soils, under rocks, or in rotting wood. The newly emerged adults fly for a short period of time, then enter the water and lose the ability to fly (Merritt and Cummins 1984). Little is known about the diet of this species.

Habitat and Status in the Project Area. Suitable habitat for the Wawona riffle beetle occurs in the Merced River through Yosemite Valley and El Portal and in the South Fork of the Merced River in Wawona. It was described and named after specimens collected in the South Fork of the Merced River in Wawona.

General Distribution. The Bohart’s blue butterfly has been collected in Briceburg (Mariposa County), the Merced area, Fresno County, and east of Johnsondale in Tulare County; however, additional collecting efforts would probably indicate a broader distribution (USFS 1994a).

Status. The Bohart’s blue butterfly is vulnerable due to its limited distribution and its apparent dependence upon one plant species.

Reproductive Biology, Breeding Habitat, and Diet. Adults are active in late April, May, and early June and have been observed on flowers of the pink spineflower (Chorizanthe membranacea), which may also be the larval foodplant. The pink spineflower is common in grassland, chaparral, and foothill woodland habitat at about 5,000 feet throughout much of central and northern California (Hickman 1993). At the type locality in Briceburg, chaparral is present on slopes above the Merced River, with scattered patches of riparian scrub and woodland along the banks of the river (VOLPE 1997).

Habitat and Status in the Project Area. Suitable habitat in the form of vegetation and host plants appears to be present in El Portal, but no specimens of Bohart’s blue butterfly have been seen or collected in this area.

Plants

General Ecology and Distribution. This native perennial herb in the mustard family occurs in California and Nevada and is considered to be extremely rare.

Habitat and Status in the Project Area. Tiehm's rock cress occurs above Tioga Pass on granitic soils in alpine fell-fields on the slopes of Mt. Dana.

General Ecology and Distribution. Congdon's lomatium is a perennial herb restricted to serpentine and metamorphic soils in chaparral, gray pine, and oak woodlands. This Sierra Nevada endemic is known only from Tuolumne and Mariposa Counties.

Habitat and Status in the Project Area. Habitat for this species occurs in the El Portal area.

General Ecology and Distribution. The slender-stemmed (Hetch Hetchy) monkeyflower is an annual herb in the snapdragon family. It is endemic to California and limited to Mariposa and Tuolumne Counties. It is found in vernally moist habitats, typically in gravelly soils and meadows and seeps, in the lower to montane forest zone of the Sierra Nevada.

Habitat and Status in the Project Area. Occurs in the open meadow and woodland area of Hazel Green Ranch.

General Ecology and Distribution. Bolander's clover is an annual herb endemic to meadows of the Sierra Nevada in the montane coniferous zone (Ratliff and Harding 1993). It is found in a narrow elevation band between about 6,500 to 7,500 feet in elevation. It is limited to Fresno, Madera, and Mariposa Counties and found only in Yosemite National Park and the Sierra National Forest in California (Ratliff and Denton 1993). In 1991, there were only 20 meadows with known populations (Ratliff and Denton 1993).

Habitat and Status in the Project Area. Bolander's clover is not found in the project area. Though it does not occur in Monroe Meadow, which is directly adjacent to Badger Pass, it is found in moist meadows and wet forest understory in meadows in the Badger Pass area.

| Table of Contents | Appendix A | Appendix B | Appendix C | Appendix D | Appendix E | Appendix F | Appendix G |
| Appendix H | Appendix I | Appendix J | Appendix K | Appendix L | Appendix M | Appendix N |

| Chapter 1-3 | Chapter 4 Part 1 | Chapter 4 Part 2 | Chapter 5 | Chapter 6-8, K-1 |

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