Chapter IV. Existing Environment (cont.)

California State Endangered Species

Wildlife

General Distribution. The peregrine falcon is a neotropical migrant that occurs throughout the world, except in Antarctica. This species is found breeding, migrating, or wintering throughout most of California, except in the southeast. Active nesting sites are known along the coast north of Santa Barbara, in the Sierra Nevada, and in other mountains of northern California (Zeiner et al. 1990). Nest cliffs are found up to 7,500 feet in elevation, but most are below 4,500 feet (Monk et al. 1988). In the western Sierra Nevada, peregrines are found from the annual grassland through the lodgepole pine zones, in all successional stages (Verner et al. 1980).

Status. The peregrine falcon was recently delisted from federal endangered status, but is remains a California state endangered species.

Reproductive Biology and Breeding Habitat. Peregrines have relatively strict nesting requirements: vertical cliff habitat with large potholes or ledges that are inaccessible to land predators. They appear to prefer sheer cliffs at least 150 feet high that have a large cave or overhung ledge large enough to accommodate three to four nestlings (Monk et al. 1988). Pairs tend to return to the same nesting cliff (DeGraaf et al. 1991) or alternate between two different nesting cliffs in different years (Monk et al. 1988). They favor habitats with a high avian prey population, such as coastal areas or wetlands with large breeding populations of birds (Monk et al. 1988).

Diet and Foraging Habitat. The primary prey of peregrine falcons is a variety of bird species, ranging up to ducks in size, with pigeons and doves preferred prey in some areas. Mammals, insects, and fish are also sometimes taken (Zeiner et al. 1990). In inland California, including the Sierra Nevada, band-tailed pigeons, woodpeckers, and jays are among preferred prey (Verner et al. 1980). Peregrine falcons forage over a variety of habitats, including wooded areas, marshes, open grasslands, and bodies of water (USFWS 1982). Areas with high populations of birds, such as coasts or wetlands, are especially valuable (Monk et al. 1988).

Prey Habitat Needs. The bird species preyed upon by peregrine falcons are best supported in a landscape made up of various habitat types in various successional stages. This would include hardwood and coniferous forests, open woodlands and shrublands, riparian areas, and abundant snags. The assemblage of such habitats in natural distribution and structure would provide prey in natural abundance and diversity.

Habitat and Status in the Project Area. Prior to 1978, there was a 37-year absence of nesting records for the peregrine falcon in Yosemite, which roughly coincides with declines in numbers throughout North America and Europe (Assay and Davis 1984). Currently, there are three active nest sites in Yosemite Valley and one historic nest site near the Coulterville Road in the Merced River canyon (Thompson 2000). A pair of peregrine falcons appeared to be nesting on Wawona Dome in 1990, but no young were fledged, and no subsequent observations of peregrine falcons in this location have been made.

General Distribution. The great gray owl is a circumpolar species, but is considered rare throughout its range. In California, the center of abundance of this species is the Sierra Nevada, specifically in the Yosemite area (Winter 1986). The Sierra Nevada population of great gray owls marks the most southerly population in the world (Winter 1985; Reid 1989).

Status. Surveys in Yosemite National Park and adjacent national forests estimate the California population of great gray owls at 100 to 200 birds (Winter 1986). Recent population declines in California may be due to habitat degradation from logging and grazing.

Reproductive Biology and Breeding Habitat. Great gray owls form monogamous pairs that breed from about March to August. Eggs hatch from mid-May to mid-June, and young fledge in early June to early July. The young leave the nest before they can fly and remain around the nest through August. In the Sierra Nevada, great gray owls nest in mature red fir, mixed conifer, or lodgepole pine forests near wet meadows or other vegetated openings (Zeiner et al. 1990). Preferred breeding habitat is pine and fir forests near montane meadows that ranges from 2,460 to 7,380 feet in elevation (Winter 1986). In California, all reported great gray owl nests have been in the tops of large-diameter broken snags (Winter 1980). Nest snags are usually within a few hundred feet of a meadow. High snag densities may be critical for nesting habitat, since not all snags form top depressions suitable for nests. Nesting success is believed to depend on the abundance of voles (Winter 1986).

Diet and Foraging Habitat. Great gray owls feed primarily on rodents captured in meadows, but may also take some birds (Zeiner et al. 1990). In Yosemite National Park, recent surveys found that voles and pocket gophers make up 90% of the prey biomass in pellets (Winter 1986; Reid 1989). Owls in Yosemite restrict foraging to open meadows (Reid 1989). Adequate numbers of hunting perches are also important (Winter 1981; 1982). Meadows used by great gray owls are generally at least 25 acres in area and are in good ecological condition.

The great gray owl migrates downslope in winter. Winter ranges of the great gray owl in the Yosemite area include Big Meadow in Foresta, Wawona, Ackerson Meadow in the Stanislaus National Forest, and ranch land near Midpines (Mariposa County) in Jerseydale, Lush Meadows, and Bootjack (Skiff 1995).

Forested land from about 2,000 to 5,000 feet in elevation that contains openings suitable for vole and gopher populations is critical to sustain owls during the winter (Skiff 1995).

Habitat and Status in the Project Area. Great gray owls are regularly seen in meadows at Crane Flat, Foresta, Wawona, and along the Glacier Point Road. McCauley Meadow near Foresta is occasionally used by juvenile males driven out of primary meadows by dominant males, or as a transition meadow when there is a large snowpack in primary meadows. It is not used for nesting. Although great gray owls have not been seen in Monroe Meadow at Badger Pass, the species is frequently seen in nearby meadows (Skiff 1995) and could occasionally use Monroe Meadow without being detected.

Past research and recent surveys have not confirmed the presence of great gray owls at Hazel Green Ranch, but the meadows at this location are recognized as potential habitat, based upon their size and elevation (Skenfield 1999).

Meadows in Yosemite Valley appear to be good winter and staging habitat for great gray owls, but recent records in this location are rare. This could be due to the amount of human disturbance that occurs in this area. The fact that the range of nearly the entire California population of great gray owls is centered over Yosemite reflects the relatively intact condition of habitats in the park.

General Distribution. The willow flycatcher is a neotropical migrant that breeds in riparian and moist meadow willow thickets in the U.S. and southern Canada (AOU 1983). In California, it is a rare to locally uncommon summer resident in wet meadow and montane riparian habitats from 2,000 to 8,000 feet in elevation. Three subspecies of willow flycatcher are present in California, with two subspecies—E. t. brewsteri (which is also a federal species of concern) and E. t. adastus—possible in Yosemite. Research currently underway is attempting to determine the exact range of each subspecies, or whether areas like Yosemite represent an area of intergrade between the two subspecies (Whitfield 2000). A statistically significant association has been found between meadow size and the occurrence of the willow flycatcher, showing that birds favor larger meadows (Serena 1982).

Status. Willow flycatchers historically nested in California wherever mesic willow thickets occurred (Grinnell and Miller 1944). In recent decades, however, breeding populations have disappeared from most lower-elevation habitats in the state. Alteration and destruction of riparian and meadow habitats is thought to be the principal cause for this decline (Remson 1978). Other contributing factors may include nest parasitism by brown-headed cowbirds, disturbance from grazing, and disturbance on wintering grounds (Serena 1982). The entire state population of willow flycatchers is thought to number around 200 pairs (CDFG 1991).

Reproductive Biology and Breeding Habitat. Breeding occurs from late May/early June to September, when an average of three to four eggs are laid in an open-cup nest placed about 1.5 to 10 feet high in a willow or other deciduous riparian shrub, usually near slow-moving streams, seeps, or standing water (Valentine et al. 1988). Nests are typically placed on the edges of vegetation clumps, which makes them susceptible to damage from wind, cattle, and predators (KRCD 1985). Willow flycatcher nests are frequently parasitized by brown-headed cowbirds. Parasitism occurs more often in lowland habitats than in higher elevations of the Sierra Nevada (Harris 1991), apparently due to differences in breeding period of cowbirds and willow flycatchers at higher elevations (Verner and Ritter 1983).

Diet and Foraging Habitat. Willow flycatchers forage by either gleaning insects from vegetation while flying, or by waiting on an exposed perch and capturing insects in flight (Ettinger and King 1980; Sanders and Flett 1989). As such, deciduous trees and shrubs interspersed with open areas enhance the quality of foraging habitat.

Habitat and Status in the Project Area. Willow flycatchers formerly nested in Yosemite Valley, but were last observed in 1966. It is likely that human disturbance, habitat destruction, and brown-headed cowbird parasitism were factors in this disappearance. A greater factor, however, has probably been the Sierra-wide decline of the species that has limited the ability of park habitats to sustain a viable population. Recent records of willow flycatchers in the park include Wawona Meadow, Hodgdon Meadow near the Big Oak Flat Entrance Station, and Westfall Meadow near Badger Pass.

California State Threatened Species

Wildlife

Sierra Nevada red fox (see Federal Species of Concern section)

California wolverine (see Federal Species of Concern section)

Limestone salamander (see Federal Species of Concern section)

California State Rare Species

Plants

General Ecology and Distribution. The Yosemite onion is a narrow endemic that occurs in five known populations in the central Sierra Nevada (McNeal and Mortola 1985). This species in the lily family is found from the foothills into montane coniferous forests in rocky soils, primarily on metamorphic substrates. It is found on talus and scree slopes, ridges, metamorphic outcrops, and on the margins and cracks of large granitic slabs (Taylor 1982). It is limited in distribution to Mariposa and Tuolumne Counties.

Habitat and Status in the Project Area. The Yosemite onion is found in the vicinity of El Portal and Wawona on steep slopes generally inaccessible to casual visitation.

General Ecology and Distribution. This perennial herb in the sedge family is endemic to the Sierra Nevada and is found only in Fresno, Madera, Mariposa, and Tuolumne Counties. Tompkin's sedge is limited to foothill oak woodland and chaparral areas and along lower talus slopes in moist and shaded areas.

Habitat and Status in the Project Area. Tompkin's sedge is found sporadically from El Portal east to the vicinity of Cascade Creek.

General Ecology and Distribution. This species, a native annual herb in the aster family, is endemic to California and restricted to Mariposa County. It is found on dry, mostly south-facing metamorphic and metasedimentary outcrops in chaparral and oak woodlands. It is endemic to the main stem of the Merced River canyon near El Portal and the South Fork of the Merced River downstream of Wawona.

Habitat and Status in the Project Area. Habitat for this species occurs throughout the Merced River gorge, El Portal, and lower portions of the South Fork of the Merced River downstream of Wawona.

General Ecology and Distribution. This perennial native herb is endemic to California and limited to Fresno, Madera, and Mariposa Counties. It grows on moist, exposed metamorphic rock faces and slopes in chaparral and mixed conifer forests. The lewisia (or "bitterroot") is often found on shaded, north-facing slopes (Taylor 1982).

Habitat and Status in the Project Area. This species is known from the slopes above the Merced River above El Portal and the Merced River gorge.

California State Species of Special Concern

Wildlife

Yosemite toad (see Federal Species of Concern section)

California red-legged frog (see Federal Threatened Species section)

Foothill yellow-legged frog (see Federal Species of Concern section)

Mountain yellow-legged frog (see Federal Species of Concern section)

Northwestern/Southwestern pond turtle (see Federal Species of Concern)

Mount Lyell salamander (see Federal Species of Concern section)

Harlequin duck (see Federal Species of Concern section)

General Distribution. Cooper's hawks are found across most of the United States, inhabiting discontinuous woodlands and riparian woodlands, especially deciduous woodlands. In California, they range up to 9,000 feet in elevation in the Sierra Nevada. Dense stands of live oak, riparian deciduous, and other forest habitats near water are most frequently used by the Cooper's hawk.

Status. Numbers of Cooper's hawks have apparently declined, but this decline began to reverse after the banning of DDT in the United States in 1972 (Ehrlich et al. 1988). Low numbers of this species, however, are still of concern. Habitat destruction and the continued presence of pesticide residues could be factors that contribute to low numbers of this species. Records of Cooper's hawk in Yosemite are relatively numerous.

Reproductive Biology and Breeding Habitat. Typical nests are in the crotches of deciduous trees between 20 and 50 feet above the ground, but nests are also found on the horizontal branches of conifers, often just below the lowest live branches. Cooper's hawks usually nest in second-growth conifer stands, or in deciduous trees in riparian areas, usually near streams (Zeiner et al. 1990). Peak breeding activity occurs May through July. Only the female incubates, while the male provides food during this period.

Diet and Foraging Habitat. Cooper's hawks feed primarily on small birds, especially young birds during nesting season, but will also take small mammals, reptiles, and amphibians. They hunt in sudden flights from a perch in dense cover, pursuing prey in the air through branches. Use of cover is an important hunting strategy for hiding, approaching, and attacking prey. Cooper's hawks will also search for prey from the air, using low, gliding flights (Zeiner et al. 1990). Broken woodland and forest edges are important foraging areas.

Habitat and Status in the Project Area. Suitable habitat for Cooper's hawks is largely intact in Yosemite National Park, except for localized impacts from development, especially in Yosemite Valley. Nonetheless, Cooper's hawks are regularly seen in the Valley, often near developed areas. Habitat for the Cooper's hawk is found in all of the project areas, with the exception of Tioga Pass.

Northern goshawk (see Federal Species of Concern section)

General Distribution. Sharp-shinned hawks occur across most of North America, inhabiting woodlands and forests, hunting in openings and along edges. In California, they breed in a variety of forested habitats between 4,000 and 7,000 feet in elevation. They winter in all but the most barren and open habitats, and often descend to lower elevations.

Status. North American numbers of sharp-shinned hawks declined greatly in the early 1970s, apparently from the effects of DDT and other pesticides in the environment that caused eggshell thinning. Populations rebounded somewhat after the banning of DDT in the United States in 1972, but populations continue to be low. Likely causes include habitat destruction and continued pesticide contamination. Observations of this species in Yosemite National Park are relatively rare; some records classified as Cooper's hawk may have been sharp shinned hawks, due to their similar appearance. One record exists of a sharp-shinned hawk nest in Yosemite Valley in 1930.

Reproductive Biology and Breeding Habitat. Nests of the sharp-shinned hawk are typically located in dense stands of small conifers which are moist, cool, and well-shaded. They are often present in areas near water with little ground cover. The nest is usually placed in dense foliage against the trunk or in the main crotch of a tree, usually between 6 and 80 feet above the ground. The nest is usually very inconspicuous (Zeiner et al. 1990). Breeding habitats include ponderosa pine, black oak, riparian deciduous, mixed conifer, and Jeffrey pine. Riparian habitats are preferred, and habitat with north-facing slopes are critical.

Diet and Foraging Habitat. Diet is almost entirely small birds, with small mammals, reptiles, and insects rarely taken. Prey is surprised in sudden flights from a perch; the hawk may also hunt in low, gliding flights. Hunting often occurs in forest openings and edges, and brushy areas.

Habitat and Status in the Project Area. Sharp-shinned hawks are found throughout wooded habitat in the park from 4,000 to 7,000 feet in elevation. Habitat is largely intact in the park, except for localized habitat destruction from roads and development. Suitable habitat for the sharp-shinned hawk is found at Yosemite Valley, Badger Pass, Hazel Green, El Portal, and the Big Oak Flat Entrance Station.

General Distribution. Prairie falcons have a widespread distribution in open habitats of mountains, plains, deserts, and grasslands of western North America. In California, the species is found in most open habitats, avoiding densely forested areas. Their range includes southern deserts, Sierra Nevada Coast Ranges, San Joaquin Valley, and Great Basin habitats. The prairie falcon is also found in annual grasslands and alpine meadows, but prefers perennial grasslands, savannahs, rangeland, desert scrub, and some agricultural fields (Zeiner et al. 1990). Prairie falcons are not found along coastlines. In the Sierra Nevada, the species is found from open foothill habitats to alpine meadows and open lodgepole pine forests, and ranges to above the treeline in late summer.

Status. Declines of prairie falcons in California have been linked to pesticide and mercury poisoning, as well as habitat destruction, primarily from agriculture (Ehrlich et al. 1988). Surveys in 1971 and 1972 of former traditional prairie falcon nest sites within 48 miles of the San Joaquin Valley found 32 of 33 sites unoccupied (Garrett and Mitchell 1973).

Reproductive Biology and Breeding Habitat. Breeding occurs from mid-February to mid-September, with a peak between early May and early August. Formerly, breeding mostly occurred below coniferous forests, but most remaining pairs breed at higher elevations. Nest sites are usually on a cliff ledge that overlooks a large open area (Verner and Boss 1980). Clutch size ranges from three to six, with five the most common.

Diet and Foraging Habitat. Prey is primarily small mammals and small to medium-sized birds taken in open habitats. Prey are hunted in high, soaring flight or flushed and pursued in low flight.

Habitat Status in the Project Area. With the great declines in prairie falcon numbers in lower elevations of California, the open mountain habitats of the Sierra Nevada, as occur in Yosemite, are apparently among the last strongholds of the species in the state. Suitable habitat in potential project areas, as confirmed by observations, includes Tioga Pass, Yosemite Valley, and Foresta. The 1990 A-Rock Fire likely improved the extent and quality of habitat for prairie falcons by creating a more open landscape. The reduction in meadow habitats in Yosemite Valley from conifer invasion has likely reduced habitat quality in that area.

General Distribution. Golden eagles occur over most of North America, ranging from high alpine habitats to low deserts. Nearly all nesting in the United States occurs west of the Great Plains, with the rest of the range used primarily by migrants (Palmer 1988). In California, the preferred habitat is typically rolling foothills, mountainous areas, sage-juniper flats, and desert (Zeiner et al. 1990). In the Sierra Nevada, golden eagles favor grasslands and areas of shrubs or saplings, and open-canopied woodlands of young blue oaks. In late summer, they often range to above timberline (Zeiner et al. 1990).

Reproductive Biology and Breeding Habitat. In the Sierra Nevada, golden eagles breed from mid-January to late September, with a peak between late April and August. Nests are typically on a cliff ledge with a good view of surrounding habitat, at elevations usually below 8,000 feet. Large trees or snags are also occasionally used (Verner and Boss 1980). Clutch size ranges from 1 to 3 eggs, but is usually 2, which are laid from early February to mid-May. Incubation lasts from 43 to 45 days, and the nestling period lasts 65 to 70 days (Zeiner et al. 1990).

Diet and Foraging Habitat. Golden eagles feed mostly on rabbits and rodents, but may also take other mammals, birds, reptiles, and carrion. Open terrain is needed for hunting, such as grasslands, deserts, savannahs, and forest and shrub habitats in early successional stages (Zeiner et al. 1990). Golden eagles most often hunt by soaring 100 to 300 feet above the ground, or may fly low, following the terrain to surprise prey. They may also hunt from a perch, flying directly to sighted prey.

Habitat Status in Project Area. The most recent observations of golden eagles come from El Portal and Foresta, likely due to the relatively open terrain in these areas. In most years, a nesting pair of golden eagles occupies a nest site on Elephant Rock in the Merced River gorge east of El Portal. Sightings also occur in Yosemite Valley, although these appear to be transient birds. Summer sightings at high-elevation areas, such as Tioga Pass, are not uncommon. Overall, the relatively intact habitats in Yosemite are beneficial to golden eagles, and recent large fires in the park have likely expanded the area of suitable habitat by providing more open terrain.

Bald eagle (see Federal Threatened Species section)

General Distribution. Merlins have wide distribution in the northern hemisphere. Their range covers all of North America, except for some arctic regions. Merlins do not breed in California. Birds seen here are migratory, wintering from September to May, and usually below 4,000 feet in elevation.

Status. In recent decades, numbers of merlin have declined markedly from unknown causes. Some data suggest pesticides or heavy metals in the food chain may be a factor (Ehrlich et al. 1988). Records of merlin in Yosemite are rare. The last reported sighting occurred in 1989 in Foresta.

Reproductive Biology and Breeding Habitat. Merlins do not breed in California, but in the northern parts of North America where they do breed, tree cavities and the abandoned nests of other birds are primary nest sites. In some areas, cliffs may be used, and some nests may even be established on the ground (Palmer 1988). Nearby open terrain for hunting appears to be an important factor. Clutches of 4 to 6 eggs are laid, usually in May, and incubated for around 30 days.

Diet and Foraging Habitat. Primary prey are small birds, but small mammals and insects are also taken. In California, coastlines, open grasslands, savannahs, woodlands, lakes, wetlands, edges, and early successional stages are preferred habitat. Hunting occurs in low flights, capturing prey in short dives and pursuits.

Habitat Status in the Project Area. Likely areas for merlins, based upon elevation and habitat, include Foresta, El Portal, Wawona, and Yosemite Valley. Concentrated development in these areas, especially in east Yosemite Valley, has likely affected local habitat quality for merlins. Overall, however, park habitats are relatively intact. Recent large fires in Yosemite have likely improved merlin habitat quality by creating more forest openings.

General Distribution. Long-eared owls are found across most of the United States, but are uncommon throughout their range. In the Sierra Nevada, this species is found from blue oak savannah up to ponderosa pine and black oak habitats, usually in association with riparian habitats. Long-eared owls will also use live oak thickets and other dense stands of trees for roosting and nesting (Zeiner et al. 1990).

Status. Numbers of long-eared owls in California have been declining since the 1940s. Known factors in this decline are destruction and fragmentation of riparian and live oak habitats, but other factors may also be present. Records of long-eared owls in Yosemite are few, including one nesting record in Yosemite Valley in 1915.

Reproductive Biology and Status. Preferred nest sites are in trees with dense canopy coverage. Proximity of this habitat to meadow edges for hunting enhances quality. Old crow, hawk, magpie, or squirrel nests are often used as nests. Breeding occurs from early March to late July, with usually four to five eggs per nest.

Diet and Foraging Habitat. Prey is searched for in low, gliding flights in open areas and occasionally woodland and forested habitats (Zeiner et al. 1990). Prey consists mostly of voles and other small rodents, and occasionally other birds.

Habitat and Status in Project Area. Long-eared owl habitat is largely intact in the park, except for localized habitat destruction from roads and development. Suitable habitat for the long-eared owl is found in El Portal, Wawona, and Yosemite Valley.

California spotted owl (see Federal Species of Concern section)

General Distribution. Breeding range of the yellow warbler extends over most of North America, and wintering range extends to northern South America. In California, yellow warblers breed over much of the state where suitable breeding habitat occurs. Some yellow warblers winter in extreme southern California.

Status. Destruction of riparian habitats and nest parasitism by brown-headed cowbirds have led to declines in lowland populations of yellow warblers.

Reproductive Biology and Habitat. Yellow warblers breed primarily in riparian woodlands from coastal, valley, and desert lowlands, up to 8,000 feet in the Sierra Nevada. Other breeding habitat includes montane chaparral, ponderosa pine, and mixed conifer where substantial amounts of brush occur (Zeiner et al. 1990). Breeding occurs from mid-April to early August, with peak activity in June. Three to six eggs are laid in an open-cup nest placed from 2 to 16 feet above the ground in a shrub or deciduous sapling. Nesting territories often contain heavy brush understory for nesting and tall trees for foraging and singing (Zeiner et al. 1990).

Diet and Foraging Habitat. Food of yellow warblers consists primarily of insects and spiders that are gleaned from the canopy of deciduous trees and shrubs. Occasionally, insects are hawked from the air, or berries are eaten.

Habitat and Status in the Project Area. Overall, riparian habitats are relatively intact, compared to areas outside the park, but localized destruction of such habitat from foot traffic, primarily in east Yosemite Valley, has likely affected yellow warblers. Breeding habitats in forested areas are, likewise, relatively intact, but a long history of fire suppression in the park may have affected habitat quality in areas where an unnaturally high degree of canopy closure limits understory growth. Suitable habitat for the yellow warbler occurs at all potential project sites except Tioga Pass.

General Distribution. The pallid bat is found throughout California, primarily in the low to mid elevations, although it has been found to elevations of over 10,000 feet in the Sierra Nevada. It is found in a variety of habitats, from desert to coniferous forest and nonconiferous woodlands. It is particularly associated with ponderosa pine, redwood, and giant sequoia habitats. It selects a variety of day roosts, including rock outcrops, mines, caves, hollow trees, buildings, and bridges. Recent research suggests a high reliance on tree roosts. It commonly uses bridges for night roosts.

In 1994, mist-net bat surveys took place in Tuolumne Meadows, Pate Valley, and Wawona. The pallid bat was captured in Pate Valley and Wawona (Pierson and Rainey 1995). It was also captured in Yosemite Valley in 1993 (Pierson and Rainey 1993).

Status. Declining populations of pallid bats may be caused by habitat destruction and fragmentation and the use of pesticides.

Reproductive Biology and Breeding Habitat. The pallid bat produces one to two young per year, but usually two, with birth occurring in May to June. Nursery colonies may contain up to several hundred females, but generally fewer than 100.

Diet and Foraging Habitat. The diet of the pallid bat is primarily ground-dwelling arthropods (scorpions, grasshoppers, long-horned beetles, Jerusalem crickets), but also includes large moths. Foraging occurs in and among vegetation as well as on the ground surface. Pallid bats may land and pursue prey on the ground.

Habitat and Status in the Project Area. Mist-net surveys took place in Yosemite Valley in 1993 at Mirror Lake, Cook's Meadow, El Capitan Meadow, and Yosemite Creek at the base of Lower Yosemite Fall. The pallid bat was captured only at the Yosemite Creek site (Pierson and Rainey 1993). It was also captured in 1994 in mist-net surveys in Wawona (Pierson and Rainey 1995). The pallid bat is expected in all of the project sites, with the exception of Tioga Pass.

General Distribution. In California, the Townsend's big-eared bat is found from low desert to mid-elevation montane habitats. The majority of records are from low to moderate elevations, though the Townsend's big-eared bat has been found from sea level to almost 10,000 feet in elevation. Maternity colonies have been found to more than 5,000 feet in elevation in the Sierra Nevada. The Townsend's big-eared bat is concentrated in areas with mines (particularly in the desert regions to the east and southeast of the Sierra Nevada) or caves (in the northeast portion of California and karstic regions in the Sierra Nevada and Trinity Alps) as roosting habitat (Pierson and Fellers 1998).

In 1994, mist-net bat surveys took place in Tuolumne Meadows, Pate Valley, and Wawona. The Townsend's big-eared bat was captured in Wawona (Pierson and Rainey 1995). It was also captured in Yosemite Valley in 1993 (Pierson and Rainey 1993).

Status. Numbers of Townsend's long-eared bat appear to have decreased due to habitat destruction and fragmentation, pesticides, and disturbance of maternity colonies in mines and buildings.

Reproductive Biology and Breeding Habitat. Mating takes place in winter roosts from October to February. Females form maternity colonies and support one young per year. The gestation length varies from 56 to 100 days. Young bats are capable of flight at 2.5 to 3 weeks of age (Pierson and Fellers 1998). Birth occurs from May to July. Historically, maternity colonies contained several hundred females. Males roost individually. Current research shows that colony size is now typically made up of 35 to 150 individuals (Wildlife Society 1996).

Diet and Foraging Habitat. The Townsend's big-eared bat feeds primarily on small moths. In California, the bats tend to forage near native vegetation (Wildlife Society 1996).

Habitat and Status in the Project Area. Mist-net surveys took place in Yosemite Valley in 1993 at Mirror Lake, Cook's Meadow, El Capitan Meadow, and Yosemite Creek at the base of Yosemite Falls. The Townsend's big-eared bat was captured only at Mirror Lake (Pierson and Rainey 1993). It was also captured in 1994 in mist-net surveys in Wawona in close proximity to the South Fork of the Merced River (Pierson and Rainey 1995). The Townsend's big-eared bat is expected in all of the project sites, with the exception of Tioga Pass.

The Townsend's big-eared bat is also found in a barium mine on U.S. Forest Service land in El Portal. This mine is fenced and protected from disturbance.

Spotted Bat (see Federal Species of Concern section)

Yuma myotis bat (see Federal Species of Concern section)

Greater western mastiff bat (see Federal Species of Concern section)

General Distribution. White-tailed hares have a wide distribution over the plains and shrubby mountain areas of the northern United States and southern Canada. In California, the preferred habitats of the white-tailed hare are sagebrush, subalpine conifer, juniper, alpine dwarf-shrub, and perennial grasslands. It is also known to use wet meadows and early successional stages of various conifer types (Zeiner et al. 1990). White-tailed hares are most abundant above 8,500 feet, but may descend to lower elevations in winter, mostly on the east slope of the Sierra.

Status. Numbers of white-tailed hares in California have declined drastically in recent decades, and now the hare exists in fragmented populations. Overgrazing by livestock has been identified as a principal factor in this decline, with cultivation and other development in habitat also having negative effects (Zeiner et al. 1990). Although habitats in Yosemite are relatively intact, reported observations of white-tailed hares are rare, either due to the mainly nocturnal behavior of the species or reduction in numbers from regional effects on the species.

Reproductive Biology and Breeding Habitat. In California, white-tailed hares breed from February to July. An average of 4 to 5 young are born in a litter. In other parts of its range, 3 to 4 litters may be produced in a year, but, in California, no more than one litter may be produced. Young are born in a shallow nest on the ground, usually concealed under a bush.

Diet and Foraging Habitat. In spring through early fall, grasses and forbs form the bulk of the white-tailed hare's diet. Important habitats at this time of year are open alpine and mountain meadows, and open stands of trees with some brush and an herbaceous understory. In winter, the bark, buds, and twigs of shrubs such as sagebrush, creambush, and small trees are consumed.

Habitat Status in Project Area. Tioga Pass is the only project site that is likely to have white-tailed hares. The meadows, willow thickets, shrubby ridgetops, and open stands of lodgepole pine in this location are likely habitats.

Sierra Nevada mountain beaver (see Federal Species of Concern section)

Pacific fisher (see Federal Species of Concern section)

Park Rare Species

Sugar stick (Allotropa virgata)

General Ecology and Distribution. Sugar stick is found on dry, well-drained soils with abundant coarse woody debris and deep humus. It is found at lower elevations in closed-canopy forest stands with trees as young as 60 years, and in mature and old growth forests of Douglas-fir, white fir, and other vegetation types. It is widespread but rare throughout its range. It is a perennial saprophytic plant that requires an association with a fungus and vascular plants for establishment. During the growing season, the plant is unmistakable and conspicuous, with pink and white striped stems up to over 3 feet in height.

Habitat and Status in the Project Area. This species occurs at scattered locations throughout Yosemite Valley. Fire is thought to play an important role in its life cycle, and this species may be at risk because of many decades of successful fire suppression, as well as destruction and fragmentation of its habitat. Low-intensity underburns might be essential for its survival.

Snapdragon (Antirrhinum leptaleum)

General Ecology and Distribution. Spurred snapdragon, an annual herb, is endemic to California and limited to the seasonally moist areas in the foothill and Sierra Nevada counties.

Habitat and Status in the Project Area. The snapdragon is restricted to small washes and shallow ditches in disturbed areas in Foresta and Wawona.

Sweetwater mountains milkvetch (Astragalus kentrophyta var. danaus)

General Ecology and Distribution. This perennial herb in the pea family is endemic to California and is restricted to the subalpine and alpine areas of the park, in rocky soils and fell-fields.

Habitat and Status in the Project Area. The milkvetch occurs on alpine summits above Tioga Pass on metamorphic bedrock substrates.

Black and white sedge (Carex albonigra)

General Ecology and Distribution. This perennial herb in the sedge family occurs in meadow, marsh, and seep spring areas and slopes in rocky soils within alpine fell-fields. It is a strictly an alpine species and is restricted to the southern Sierra Nevada in California, although it occurs in other mountainous areas of North America.

Habitat and Status in the Project Area. It is locally rare and occurs in the vicinity of Tioga Pass in perennially moist sites.

Capitate sedge (Carex capitata)

General Ecology and Distribution. This perennial herb is in the sedge family and is found throughout the Sierra Nevada as well as other high-elevation sites in North America. It occurs in meadow and perennially moist areas in subalpine and alpine forests and fell-fields, in rocky to loamy soils.

Habitat and Status in the Project Area. This herb is restricted to the Sierra Nevada and is strictly an alpine species in Yosemite.

Congdon's sedge (Carex congdonii)

General Ecology and Distribution. This perennial herb in the sedge family is restricted to subalpine and alpine talus slopes and fell-fields and is endemic to California.

Habitat and Status in the Project Area. It is found at high elevations in metamorphic and granitic talus slopes.

Indian paintbrush (Castilleja foliolosa)

General Ecology and Distribution. This perennial herb is found primarily in California in low-elevation foothill woodlands, grasslands, and chaparral regions. The species has reddish bracts covered with a dense mat of fine hairs.

Habitat and Status in the Project Area. It is found on dry, rocky, open slopes on the edge of chaparral areas in the El Portal area, and habitat exists throughout the Merced River gorge and El Portal area.

Alpine cerastium (Cerastium beeringianum)

General Ecology and Distribution. This perennial herb in the pink family is native to California and isolated to subalpine and alpine areas. It commonly occurs adjacent to perennial or nearly perennial snow banks where moisture is consistently available.

Habitat and Status in the Project Area. This herb is found near snow banks on granitic and metamorphic slopes above Tioga Pass.

Small's southern clarkia (Clarkia australis)

General Ecology and Distribution. This annual herb is endemic to California and restricted to Madera, Mariposa, and Tuolumne Counties. It is found in foothill woodlands and lower montane forests.

Habitat and Status in the Project Area. This herb is found in Foresta in open areas.

Sierra claytonia (Claytonia nevadensis)

General Ecology and Distribution. This perennial herb is endemic to California and limited to alpine fell-fields in perennially moist areas in granitic and metamorphic substrates. In Yosemite, it remains from pre-glacial periods in small, isolated populations.

Habitat and Status in the Project Area. This herb is found along small streams flowing from higher peaks above Tioga Pass.

Child's blue-eyed Mary (Collinsia childii)

General Ecology and Distribution. This annual herb is endemic to California and limited to the central and southern Sierra Nevada, reaching the northern extent of its range in southern Mariposa County. It occurs on shaded slopes and in open California black oak and mixed coniferous woodlands.

Habitat and Status in the Project Area.This species occurs in Wawona; habitat exists throughout the basin on shaded slopes.

Collinsia (Collinsia linearis)

General Ecology and Distribution. This annual herb in the snapdragon family is primarily limited to California, with some extensions into adjacent states. It is found in lower- to mid-elevation coniferous forests on rock outcrops and dry slopes. It reaches the southern extent of its range in Mariposa County.

Habitat and Status in the Project Area.Habitat for this species occurs throughout the Merced River gorge and in the El Portal area, where it is restricted to dry, metamorphic rock outcrops along the metamorphic-granitic contact zone.

Draba (Draba praealta)

General Ecology and Distribution. Draba is a perennial herb in the mustard family and is confined to western North America in alpine wetland environments. Its westernmost populations are found along the crest of the Sierra Nevada in Inyo and Mono Counties, residing in localized perennially wet seeps.

Habitat and Status in the Project Area. This herb occurs on the slopes of Mt. Dana above Tioga Pass in small, isolated populations.

Round-leafed sundew (Drosera rotundifolia)

General Ecology and Distribution.This species, an insectivorous perennial herb, is found throughout North America, but it is limited to sphagnum bogs and acidic wetlands, which is an unusual habitat in the Sierra Nevada in the lower to upper montane coniferous forests.

Habitat and Status in the Project Area.Habitat for this species exists in isolated areas in Wawona and Yosemite Valley.

Stream orchid (Epipactis gigantea)

General Ecology and Distribution.This species, a perennial herb in the orchid family, is widely distributed throughout California and North America. In Yosemite, it is restricted to moist granitic ledges and planted in landscaped areas.

Habitat and Status in the Project Area.This species occurs in Yosemite Valley within a number of landscaped areas. Former populations above Happy Isles were obliterated by the rockfall in 1996. Natural habitat for this species exists throughout the Valley in perennially moist, shaded areas.

Desert fleabane (Erigeron linearis)

General Ecology and Distribution.This is a perennial herb in the aster family, native to California and confined to western North America. It reaches the southwestern extent of its range on the Sierra Nevada crest in the vicinity of Mt. Dana in rocky soils on slopes.

Habitat and Status in the Project Area.This species occurs at the granitic-metamorphic contact zone on the slopes of Mt. Dana.

Rambling fleabane (Erigeron vagus)

General Ecology and Distribution.This perennial herb in the aster family is confined to western North America. It reaches the northern extent of its range on the Sierra Nevada crest in Tuolumne County. It occurs exclusively in rocky soils throughout alpine fell-fields.

Habitat and Status in the Project Area.Occurs in isolated populations on the slopes of Mt. Dana and on adjacent alpine peaks surrounding Tioga Pass.

Fawn-lily (Erythronium purpurascens)

General Ecology and Distribution.This perennial herb is endemic to California and the Sierra Nevada. It grows along shaded streams and river corridors in montane coniferous forests.

Habitat and Status in the Project Area. This species is known from riparian corridors in the eastern end of Yosemite Valley. It was collected in the past for its showy flowers.

Northern bedstraw (Galium boreale ssp. septentrionale)

General Ecology and Distribution.This species, a perennial herb in the bedstraw family, is found in moist areas within montane coniferous forests. It has a disjunct population in Mariposa County, within Yosemite Valley meadows. The remainder of its range is in northern California and the Pacific Northwest.

Habitat and Status in the Project Area.In Yosemite, this species is known from a number of wet meadows in Yosemite Valley, and wet portions of drier meadows and oxbows.

Dane's dwarf gentian (Gentianella tenella ssp. tenella)

General Ecology and Distribution.This annual herb in the gentian family is found in subalpine forests and alpine fell-fields, meadows, and seeps throughout North America. In Yosemite, relict populations left intact from Pleistocene glaciation are found on the slopes of the Sierra Nevada crest.

Habitat and Status in the Project Area. It is found in alpine fell-fields at high elevations on the slopes of Mt. Dana and other peaks surrounding Tioga Pass.

Goldenaster (Heterotheca sessiliflora ssp. echioides)

General Ecology and Distribution.This perennial herb in the aster family is limited to grasslands and open California black oak woodlands throughout the southern portions of California. It reaches the northernmost extent of its range in Tuolumne County.

Habitat and Status in the Project Area.Small, isolated populations of this species occur in the Foresta area. New populations have recently been discovered that are likely a result of the 1990 A-Rock Fire, which opened the forest canopy and removed unnaturally deep layers of litter and duff in the basin.

Yosemite ivesia (Ivesia unguiculata)

General Ecology and Distribution.This perennial herb in the rose family is endemic to California and limited to the southern Sierra Nevada. It occurs in meadow habitats within upper montane forests and reaches the northern extent of its limited range in Mariposa County.

Habitat and Status in the Project Area.This herb occurs in meadow and wet areas east of Badger Pass.

Common juniper (Juniperus communis)

General Ecology and Distribution.This coniferous shrub in the cypress family is found throughout North America. In Yosemite, it is limited in distribution to montane and subalpine sites, where it grows on open, rocky, dry slopes.

Habitat and Status in the Project Area.This shrub grows in isolated patches at Tioga Pass and lodgepole pine forest to the west of the Tioga Road.

Pitcher sage (Lepechinia calycina)

General Ecology and Distribution.Pitcher sage, a shrub in the mint family, is endemic to California and is found on rocky slopes within foothill and lowland chaparral and canyon live oak woodlands.

Habitat and Status in the Project Area.Habitat for this species occurs throughout the Merced River gorge and El Portal.

Sierra laurel (Leucothoe davisiae)

General Ecology and Distribution.This shrub, a perennial in the heath family, is found slightly beyond California's boundaries and is restricted to wetland, bog, and moist habitats.

Habitat and Status in the Project Area.In Yosemite, sierra laurel grows adjacent to iron-rich springs and seeps in isolated locations along the Merced River and Tenaya Creek in Yosemite Valley.

False pimpernel (Lindernia dubia var. anagallidea)

General Ecology and Distribution.This annual herb in the snapdragon family is found in freshwater wetlands and meadows at low to mid elevations in California and North America.

Habitat and Status in the Project Area.False pimpernel is found in meadow soils throughout Yosemite Valley that remain moist for the duration of the plant's seasonal life span.

Congdon's monkeyflower (Mimulus congdonii)

General Ecology and Distribution.This annual herb in the snapdragon family is endemic to California. It reaches the northern extent of its range in the Sierra Nevada in Yosemite and is found in granitic soils in disturbed areas, seeps, and runoff areas on slopes.

Habitat and Status in the Project Area.Habitat for this species occurs in portions of the Merced River gorge and at El Portal.

Inconspicuous monkeyflower (Mimulus inconspicuus)

General Ecology and Distribution.This annual herb in the snapdragon family is endemic to California. It is restricted to wetlands and seasonally moist sites in lower montane forests and foothill woodlands in partial shade.

Habitat and Status in the Project Area.Isolated populations of this species occur throughout Foresta where small hillside streams and seeps provide suitable habitat.

Palmer's monkeyflower (Mimulus palmeri)

General Ecology and Distribution.This monkeyflower, an annual herb in the snapdragon family, is endemic to California and Baja California. It reaches the northern extent of its range in Yosemite. It is restricted to damp, shaded slopes under canyon live oaks in foothill, chaparral, and lower montane forests.

Habitat and Status in the Project Area.Habitat for this species occurs in portions of the Merced River gorge and at El Portal.

Pansy monkeyflower (Mimulus pulchellus)

General Ecology and Distribution.This annual herb in the snapdragon family is endemic to California and limited to Mariposa, Tuolumne, and Calaveras Counties. It is restricted to wetlands and seasonally moist sites and reaches the southern extent of its range in Foresta.

Habitat and Status in the Project Area.It is found in small, isolated, vernally moist, open, gravelly places throughout the Foresta basin.

Dwarf sandwort (Minuartia pulchellus)

General Ecology and Distribution.This annual herb is confined to western North America. It reaches the southern extent of its range in the Sierra Nevada in Mariposa County and occurs in open montane coniferous forests.

Habitat and Status in the Project Area.This herb is found on dry slopes and forest openings east of Badger Pass.

Sierra sweet-bay (Myrica hartwegii)

General Ecology and Distribution.This perennial shrub in the wax-myrtle family is endemic to California. It is limited in occurrence to streambanks and riparian communities at low to moderate elevations in the Sierra Nevada, where it forms small thickets along the river.

Habitat and Status in the Project Area.It has a patchy distribution along the South Fork of the Merced River through Wawona as well as along tributaries to the South Fork and Big Creek near the South Entrance Station.

Azure penstemon (Penstemon azureus ssp. angustissimus)

General Ecology and Distribution.This perennial herb in the snapdragon family is endemic to California and is near its southern extent in Yosemite. It is generally found in moist woodlands and open forests at lower to moderate elevations in the Sierra Nevada.

Habitat and Status in the Project Area.This herb is found in scattered locations in Yosemite Valley. It was first described from collections taken in Yosemite Valley, although that original population appears to have disappeared.

Phacelia (Phacelia platyloba)

General Ecology and Distribution.Broad-leaved phacelia is an annual herb endemic to California. It is restricted to Mariposa, Madera, and eastern Fresno Counties and is found in gravelly or rocky soils in chaparral and canyon live oak woodlands.

Habitat and Status in the Project Area.Habitat for this species occurs throughout the Merced River gorge and at El Portal.

Phacelia (Phacelia tanacetifolia)

General Ecology and Distribution.This annual herb in the waterleaf family is found throughout California and is confined to western North America. It grows in seasonally moist, sandy and gravelly open areas.

Habitat and Status in the Project Area.This species occurs at scattered locations throughout Yosemite Valley, where it blooms and sets seed early each spring.

Snow willow (Salix reticulata)

General Ecology and Distribution.This low-growing willow shrub is confined to western North America in subalpine and alpine habitats. It reaches the westernmost extent of its range in relict populations along the crest of the Sierra Nevada in Yosemite.

Habitat and Status in the Project Area.This scrub is found in wet areas and seeps within alpine fell-fields on the slopes of Mt. Dana and adjacent peaks surrounding Tioga Pass.

Wood saxifrage (Saxifraga mertensiana)

General Ecology and Distribution.This perennial herb in the saxifrage family is endemic to California and limited to the northern and central Sierra Nevada. It reaches its southern extent in Mariposa County, where it grows on mossy rocks and moist cliffs in lower to montane coniferous forests.

Habitat and Status in the Project Area.This species occurs at scattered locations in moist, shaded sites throughout Yosemite Valley.

Bolander's skullcap (Scutellaria bolanderi)

General Ecology and Distribution.This perennial herb in the mint family is endemic to California. It is primarily found in lower montane forests in the Sierra Nevada, where it occurs in gravelly soils along streambanks and in California black oak woodlands and ponderosa pine forests.

Habitat and Status in the Project Area.This species is known from isolated populations scattered throughout the Wawona basin.

Groundsel (Senecio serra var. serra)

General Ecology and Distribution.This perennial herb in the aster family is confined to western North America in montane to subalpine coniferous forests.

Habitat and Status in the Project Area.It is restricted to open coniferous forests or sagebrush scrub on the lower slopes of Mt. Dana and the slopes west of Tioga Pass.

Giant sequoia (Sequoiadendron giganteum)

General Ecology and Distribution.Giant sequoias are endemic to California and grow in 70 discrete groves in the central and southern Sierra Nevada within the montane forest belt. In Yosemite National Park, sequoias grow naturally in the Merced, Tuolumne, and Mariposa Groves.

Habitat and Status in the Project Area.Individual sequoia trees have been planted in Yosemite Valley and Wawona in landscaped and natural areas, both historically and in recent times.

Ladies' tresses (Spiranthes porrifolia)

General Ecology and Distribution.This perennial herb in the orchid family is found throughout western North America. It grows in wet meadows and bogs at low to mid elevations.

Habitat and Status in the Project Area.This species occurs at scattered locations throughout Yosemite Valley where deep, loamy soils and moist conditions prevail.

Trillium (Trillium angustipetalum)

General Ecology and Distribution.This perennial herb in the lily family is almost entirely restricted to California. It is most common in the coastal ranges of the state, but occurs in limited, small populations in the Sierra Nevada where it is found in shady areas within mature montane coniferous forests with well-developed duff and litter layers. This species may be at risk due to the lack of natural fire patterns, which allows an unnatural buildup of duff and litter to the exclusion of the plant, as well as overly intense fire behavior resulting in loss of root and plant materials through overheating.

Habitat and Status in the Project Area.This species is scattered over a 10-acre area along the south side of the South Fork of the Merced River in Wawona, near the eastern end of River Road.

Hall's wyethia (Wyethia elata)

General Ecology and Distribution.This species, a perennial herb in the aster family, is endemic to California. It is restricted to the southern Sierra Nevada foothills and lower montane forests and reaches the northern extent of its range in Yosemite.

Habitat and Status in the Project Area.It is found in open woodlands and forests in the Wawona basin.

| 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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