Birds of the Sierra Nevada. Ted Beedy
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West Side. Fairly common along most large creeks and rivers offering clear water and plentiful supplies of fish; most Sierra breeding records are from forested lakes and streams below about 8,000 feet; postbreeding birds can range to above 9,000 feet in the central Sierra in late summer and fall; flocks of 5 to 30 individuals remain on ice-free lakes and rivers at the highest elevations year-round, but most move to lower-elevation lakes, rivers, and reservoirs for winter; thousands winter on Lake Isabella.
East Side. Common at Lake Tahoe; fairly common to common in winter and during spring and fall migration at most large rivers, lakes, and reservoirs.
Red-breasted Merganser
Mergus serrator
ORIGIN OF NAMES “Red-breasted” for the coloration of breeding males; L. serrator, a sawyer, a reference to the species’ saw-toothed bill.
NATURAL HISTORY Primarily winter visitors to coastal estuaries and nearshore coastal waters, Redbreasted Mergansers rarely stray inland in winter. Like all mergansers, they are adept divers that forage for small fish; they also take mollusks, crustaceans, aquatic insects, and amphibians—captured in shallow water, but they are capable of diving up to about 30 feet. This species is often overlooked inland, especially when associating with the similar-appearing Common Mergansers. Male Redbreasted Mergansers are easily distinguished by their crested heads, grayish sides, and white neck rings set off by a reddish breast. Females, juveniles, and males in nonbreeding plumage are more difficult to identify but, compared to Common Mergansers, they are smaller, with more slender necks, thinner bills, and lack the distinct white throat patches of female Common Mergansers.
STATUS AND DISTRIBUTION Red-breasted Mergansers are winter visitors and spring and fall migrants, and there are no breeding records for the Sierra region.
West Side. Casual at Lake Almanor and Lake Isabella, mostly single birds seen far from shore.
East Side. Uncommon but regular fall, winter, and spring visitors to Lake Tahoe; rare at Boca Reservoir and Prosser Creek reservoirs, and from Crowley Lake south to Owens Valley.
Ruddy Duck
Oxyura jamaicensis
ORIGIN OF NAMES Ruddy describes the bright reddish plumage of breeding males; Gr. oxyura, sharp-tailed; L. jamaicensis, of Jamaica, where the type specimen of the species was collected.
NATURAL HISTORY Stout, chunky birds with thick heads and necks, Ruddy Ducks sit low in the water, and breeding males often cock their stiff tail feathers upward. Along with other “stiff-tailed ducks,” they differ from other waterfowl in many aspects of their biology. Males wear grayishbrown plumage for most of the year and do not molt into their bright chestnut or “ruddy” breeding plumage until March, much later than other ducks. Males display startling blue bills only when breeding, and these are used as part of elaborate and distinctive courtship displays to attract prospective females. Nest building occurs from mid- to late May, and nests are large mats of aquatic plants gathered into loose, floating platforms that rise or fall with changing water levels; most are screened from above by domes of overhanging plants. Females begin laying eggs by late May, often when nests are still under construction.
Ruddy Ducks become airborne by running across open water with their short wings beating furiously. They sink out of sight rather than flying to escape danger, much like grebes and loons. Unable to walk on land, they never stray from water, and larger lakes and ponds are preferred. They forage by skimming the water’s surface and by diving in shallow water up to about three feet; favored foods include aquatic invertebrates, zooplankton, and some aquatic plants—mostly seeds and roots.
STATUS AND DISTRIBUTION Ruddy Ducks may dot the surfaces of deep lakes, reservoirs, and sewage ponds of the Sierra in spring, fall, and winter, and nesting has been documented on both sides.
West Side. Fairly common spring and fall migrants and winter visitors, mostly in the foothills; rare individuals observed in large lakes as high as the Subalpine zone; nesting confirmed at Isabella Lake and possibly Lake Almanor; a family group was seen at 9,100 feet elevation at Upper Chain Lakes in Yosemite National Park.
East Side. Common to abundant in winter, fall, and spring, sometimes the most common ducks on large lakes and reservoirs; nesting confirmed in Sierra Valley, Tahoe Basin, Mono Basin, and Bridgeport Reservoir.
QUAIL
Family Odontophoridae
New World quail are medium-sized birds only distantly related to the quail of the Old World, but both are named “quail” for their similar appearance and habits. The Western Hemisphere species are in their own family and range from the cold, high deserts of Canada to the rainforests of southern Brazil. Members of this family generally have relatively short wings and tails, and short, powerful legs. While capable of short bursts of fast flight, especially when pursued or disturbed, they mostly travel on foot. Female quail usually lay large clutches of 10 to 20 buffy-white or brownish eggs and incubate them alone for 20 to 25 days. The precocial young can run after hatching and fly in about two weeks. This family includes 32 species but only 2, California and Mountain Quail, occur in the Sierra. The family name is derived from Gr. odontophoros, tooth bearing—a possible reference to the sharp toothlike beaks of juveniles.
Mountain Quail
Oreortyx pictus
ORIGIN OF NAMES “Mountain” for the species’ preferred habitat; quail, OF. quaille, possibly from the croaking or quacking sounds of a European species; L. ortyx, a quail; pictus from L. picta, painted, for the species’ bright colors.
NATURAL HISTORY Mountain Quail are the largest members of their family north of the tropics. Unlike other New World quail, males and females are nearly identical, with the latter having slightly shorter head plumes. These large, handsome quail are easy to miss but may be detected from April through early June by the loud, mellow wook or crow calls uttered by the males only. These ventriloquial calls are difficult to locate and at a distance might be mistaken for the single whistled notes of Northern Pygmy-Owls. These secretive birds seldom fly but instead run to dense cover when disturbed. The young are less cautious and may sometimes be seen at close range as their parents call anxiously, or even feign injury to distract human and other predators. Unlike California Quail, they rarely perch in trees, although scattered trees are usually present in their habitats.
Courting males often strut on the ground or on fallen logs to attract the attention of prospective mates. Females hide their nests in well-concealed hollows on the ground. Both parents care for the young after they hatch in late June or early July. Family groups remain together through the winter and are often joined by nonbreeding adults. Unlike California Quail, they do not typically band together with other families and winter coveys average 5 to 10 individuals.
A striking feature of the Mountain Quail’s annual cycle is the attitudinal migration in spring and fall, sometimes covering over 20 miles each way over a period of days or weeks, nearly all of it on foot. During migration, coveys may traverse atypical habitats such as dense coniferous forests and open, rocky areas. They winter below the heavy snow line down to the foothill chaparral, where some coveys live side-by-side with California Quail. When the heavy snow begins to melt in spring, Mountain Quail move upslope again.
Mountain Quail’s feeding habits are much like those of California Quail, suggesting that competition between these two species may have contributed to their altitudinal segregation while breeding. Foods of both species consist mostly of plant materials such as berries, seeds, flowers of perennial plants, along with a few insects—especially grasshoppers and ants.
STATUS AND DISTRIBUTION Mountain Quail visit foothill chaparral in fall and winter, but