Birds of the Sierra Nevada. Ted Beedy

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Birds of the Sierra Nevada - Ted Beedy

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perch high overhead in the foliage of a dense conifer. Visitors to higher forests may hear, and feel, these haunting calls echoing through the woods for hours at a time.

      Most Sooty Grouse in the Sierra breed in the Upper Conifer zone, where they can be found in open or partly brushy slopes with nearby stands of densely foliaged conifers for roosting and hooting. Large trees are preferred—especially Douglas-firs, white firs, red firs, and Jeffrey pines. Adult males arrive on breeding territories by early March, followed shortly thereafter by females and yearling males. Throughout the nesting season, the promiscuous males remain on their territories and attempt to court and mate with receptive females attracted by their calls. Once mated, a female prepares a nest by lining a shallow depression on the ground under a shrub, tree, or log with leaves and grasses.

      The young eat mostly insects, a source of protein, for at least ten days after hatching then switch to conifer needles and seeds. By late summer, mothers with young disperse both upslope and downslope from their nesting grounds, feeding in meadows and brushy hillsides, where they are often surprisingly tame. An encounter with a family group inspired John Muir (1901) to write: “One touch of nature makes the whole world kin; and it is truly wonderful how love-telling the small voices of these birds are, and how far they reach through the woods into one another’s hearts and into ours.” During spring, summer, and fall, Sooty Grouse forage mostly on the ground, eating seeds, berries, green shoots, and insects. Adults also fly up into conifers to browse on needles and buds. These hardy birds survive high-elevation winters by taking shelter in dense firs, pines, and hemlocks and eating needles, buds, and pollen cones.

      STATUS AND DISTRIBUTION In 2006 the American Ornithologists’ Union split Blue Grouse into Sooty Grouse occurring in the Sierra, Cascades, and coastal ranges of California, Oregon, and Washington, and Dusky Grouse that live in the Rocky Mountains and Great Basin. Sooty Grouse undertake both upslope and downslope movements in spring and fall. In the Pacific Northwest they are known to migrate upslope for the winter, and birds at Sequoia National Park have also been observed to undertake such “backward” migrations.

      West Side. Uncommon residents of the Upper Conifer zone, males and some females wander up to tree line after breeding where they remain until late fall; rare in Lower Conifer zone in fall and winter.

      

      East Side. Uncommon residents of ponderosa and Jeffrey pine forests up to the Subalpine zone; populations at Sagehen Creek (Nevada County) remained at their breeding elevations through the winter but similar studies are lacking from other areas.

      TRENDS AND CONSERVATION STATUS The “Mount Pinos” Sooty Grouse (D. f. howardi) is a distinct subspecies restricted to the southern Sierra, south of Kings Canyon National Park, including the Piute Mountains, as well as ranges to the south of the Sierra including the Tehachapi Mountains and Mount Pinos. Recent surveys suggest that they may be extirpated from most of the southern portion of their historical range. Extensive surveys in 2002 in the Greenhorn Mountains (northernmost Kern County) found only eight birds in what is likely now the southern edge of their range. Continuing threats include habitat degradation due to harvest of large trees, fire suppression and uncontrolled wildfires, and livestock grazing. This subspecies was added to the list of California Bird Species of Special Concern in 2008.

      Wild Turkey

      Meleagris gallopavo

      ORIGIN OF NAMES Turkey, considered foreign and exotic when the species was first introduced to Europe in the 16th century; a possible reference to Asia Minor, a source of exotic goods at that time; Gr. melagris, spotted, for the species’ patterned plumage; L. gallopavo, from gallo, a cock, and Sp. pavo, a turkey.

      NATURAL HISTORY With their dazzling, iridescent bronze plumage, Wild Turkeys are elegant versions of common barnyard turkeys, a breed domesticated during pre-Columbian times in Mexico. Wild Turkeys are not native to California, but birds captured in Mexico were first introduced to mainland California for hunting in 1908. While most early introductions failed, subsequent releases over many decades were more successful and the species is now widespread in suitable habitats throughout the state. Most of the successful introductions to California were from wild populations in Mexico, Virginia, and Texas. Attempted introductions by the California Department of Fish and Game, U.S. Forest Service, and the National Wild Turkey Federation at high elevations of Sierra, Nevada, and Placer Counties as recently as 1997 should be discouraged because this species may compete with native species of quail and grouse with unknown consequences. They have also been observed to scour entire hillsides for snakes, lizards, and invertebrates having obvious but unmeasured impacts on those species.

      Turkeys roost in trees but forage on the ground in forest openings, eating insects, green plants, seeds, acorns, and fruit. Throughout the year Wild Turkeys associate in groups, which consist during the breeding season of a “gobbler” male and his harem of four to six hens. In the Sierra the breeding season extends from late March until August, with a peak in May and June. Prior to pair formation, three to six males may strut together to attract a large group of females. The polygynous males perform courtship, a series of gobbling and strutting displays to attract females to be added to their harems. Conspicuous during courtship, fertilized hens sneak away from the immediate breeding area and are secretive when preparing to nest. They create shallow scrapes for nests and line them with leaves and grasses. Young are tended by hens alone through the winter until the following breeding season—female poults tend to remain with their mothers longer than males. With the inclusion of juveniles, winter flocks are larger than breeding flocks, and up to 100 birds might be seen foraging together on an oak-studded hillside.

      STATUS AND DISTRIBUTION In the Sierra, Wild Turkeys spend most of the year in the Foothill zone, but they can be fairly common in the Lower Conifer zone in summer; postbreeding birds have been seen up to 10,000 feet on the Kern Plateau of the southern Sierra. In winter, they move as much as 50 miles downslope in search of areas with plentiful food and little snow, especially in foothill oak woodlands and chaparral.

      West Side. Common to abundant in most areas of the foothills.

      East Side. Uncommon; established populations near Honey Lake, in Alpine County, and near Topaz Lake.

      TRENDS AND CONSERVATION STATUS Data from Breeding Bird Surveys and Sierra Christmas Bird Counts confirm the stunning increase in numbers and expansion of range for this species. In less than 30 years, Wild Turkeys have gone from unrecorded to abundant throughout the western foothills. Noted on only a couple of Sierra Breeding Bird Survey routes prior to the late 1980s, Wild Turkeys are now found consistently on more than 40 percent of the routes. Impacts to other species from this invasion are not yet evident.

       LOONS

      Family Gaviidae

      Called “divers” in Europe, loons are sleek-bodied and superbly adapted to aquatic habitats but are almost helpless on land. Laterally flattened legs, set far back on their bodies, do not enable them to walk or stand, so loons can only move on land by sliding on their bellies. Unlike grebes, which have lobed toes, loons have webbed feet. They are also strong fliers but cannot take off from land; instead, they take flight after a long running start over open water, often into a stiff wind. Once aloft, they fly with quick, shallow strokes on slender, pointed wings. On a dive, their large, paddle-like feet propel them to great depths. Genetic studies indicate that loons are unlike any other living order of birds, not related (as once thought) to grebes. Fossil evidence shows that they have an ancient lineage dating back more than 65 million years. Males and females share identical breeding and winter plumages, but males are usually larger. There are only five species of loons worldwide, and all of them breed in North America. Two species, the Pacific and Common Loons, regularly occur in the

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