Birds of the Sierra Nevada. Ted Beedy
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wintering geese, Ross’s Geese weigh only slightly more than Mallards but have much longer wingspans. They fly south from high Arctic breeding grounds in the company of Snow Geese, and the two species flock together in winter. In mixed flocks, Ross’s can be identified by their smaller size relative to the larger and more abundant Snows. Ross’s also have short, stubby bills and lack the “grin patches” of Snow Geese, and they seldom call in flight, unlike their larger cousins.
STATUS AND DISTRIBUTION Fall and spring migrants over the Sierra, Ross’s Geese might be spotted among flocks of Snow Geese on large lakes and reservoirs. “Blue-morph” Ross’s Geese can be found rarely in large flocks of “white” geese in the Central Valley but are accidental in the Sierra.
West Side. Rare spring, fall, and winter visitors at Lake Almanor and at other large reservoirs; casual south to Lake Isabella.
East Side. Uncommon in fall and winter in flocks of Snow Geese at Sierra Valley and Honey Lake; rare from Lake Tahoe south through the Owens Valley.
TRENDS AND CONSERVATION STATUS This species experienced a serious decline from the 1950s to 1970s, when its North American wintering population fell below 25,000 birds. However, full protection from hunting and the development of refuges and private wetlands have reversed this trend, and the wintering population in California now exceeds 100,000.
Cackling Goose
Branta hutchinsii
ORIGIN OF NAMES Branta, Modern English, related to “burnt” referring to the dark coloration of the head and neck; hutchinsii for Thomas Hutchins (1730–1789), an American frontiersman, surveyor, and geographer who collected the first specimen of a “small Canada goose” in northern Canada, where he was employed by the Hudson’s Bay Company.
NATURAL HISTORY Based on recent studies, the “Canada Goose complex” has been divided into two groups, including seven types of large-bodied Canada Geese (see account below) that mostly breed at lower latitudes and a group of five (one extinct) smaller forms known as Cackling Geese that breed in the high Arctic. Three forms of Cackling Geese visit California in winter, including “Aleutian” Cackling Goose (B. h. leucopareia), “Taverner’s” Cackling Goose (B. h. taverneri), and the form that once had exclusive use of the name, “Cackling” Cackling Goose (B. h. minima). The latter form is the one most likely observed with larger Canada Geese in the Sierra. Compared to Canada Geese, Cackling Geese are noticeably smaller, generally darker underneath, with shorter necks, smaller heads, and more delicate bills. The behavior and ecology of Cacklers and Canadas are similar and are covered in the following account.
STATUS AND DISTRIBUTION Cackling Geese are sometimes spotted in flocks of Canada Geese in fall, spring, and winter, but they leave for northern breeding grounds by late March.
West Side. Uncommon fall and winter visitors to the foothills below about 3,000 feet in the northern and central Sierra, and rare farther south; casual or accidental visitors to mountain lakes and meadows up to the Subalpine zone.
East Side. Rare; almost always seen in association with flocks of much more abundant Canada Geese.
TRENDS AND CONSERVATION STATUS “Aleutian” Cackling Goose populations dropped precipitously from the late 1960s to the mid-1980s, and this subspecies was listed as Endangered in 1967. The decline was due to a combination of predation from introduced Arctic foxes on their Aleutian Island breeding grounds, subsistence harvest in Alaska, and sport harvest on the wintering grounds, mainly in California. Careful management, including local control of foxes on the breeding islands and taking into account the need for fair and equitable bag limits among all hunters on the breeding and wintering grounds, promoted their rapid and encouraging recovery in recent decades. In 2001 the “Aleutian” Cackling Goose was removed from the Endangered Species list, and current populations are now well over 100,000 birds. The recent change in taxonomic status from a subspecies of Canada Goose to a full species has inspired birders to pay more attention to Cackling Geese, increasing reports and improving our knowledge of their status and distribution.
Canada Goose
Branta Canadensis
ORIGIN OF NAMES L. canadensis, of Canada, where a large portion of their population lives.
NATURAL HISTORY The loud honking of Canada Geese is often heard before their V-shaped flocks appear overhead. After forming pair bonds in their second or third winter, mated birds usually stay together for life, like other geese and swans. Extremely clannish, Canada Geese stay in family groups throughout the year. These strong social bonds led to the isolation of small breeding populations and the evolution of new subspecies across North America. Seven forms of “large-bodied” Canada Geese are currently recognized, with the most common form in the Sierra being large Great Basin “Honkers” (B. c. moffittii) that weigh up to 14 pounds. This is the only breeding subspecies in the Sierra, but other, smaller subspecies also mingle with Honkers in pastures, ponds, and golf courses in fall, winter, and spring. The smallest and darkest members of the “Canada Goose complex,” Cackling Geese (B. hutchinsii), are now recognized as a separate species (see account above).
Honkers nest commonly in the Great Basin and Sierra, and the breeding season usually extends from late February through mid-July. Monogamous pairs select nesting sites in a variety of natural and artificial sites, usually near water. Nesting pairs aggressively defend their territories, hissing menacingly if perceived predators (including humans) or neighboring geese venture too close to the nests. Artificial nesting structures are readily used, especially when located in farm ponds with irrigated pastures or golf courses nearby. They construct nests from local plant materials, usually cattails, tules, or small twigs. Nests are large, with outside diameters two feet or more, but the inner cup is only about nine inches and lined with soft down and plant fibers. Both parents care for the goslings and establish strong family ties that hold them together during migration and on the wintering grounds.
Primarily vegetarians, Canada Geese forage for grasses, clovers, and cultivated grains in pastures, wet meadows, and grain fields. More than most waterfowl, they have adapted their foraging behavior and migrations (or lack thereof) to exploit agricultural crops and other human-created food sources and habitats. Since Canada Geese are quick to use human-made habitats, they often multiply and become a nuisance in such settings because of their abundant droppings and aggressive behavior.
STATUS AND DISTRIBUTION Historically, most of California’s Canada Goose population nested farther north in the Cascades and the Great Basin and visited the Sierra in transit between their breeding and wintering grounds. In recent decades, however, creation of reservoirs, artificial ponds, golf courses, and irrigated pastures has expanded the habitat available for these adaptable geese, and they are now year-round residents in many areas.
West Side. Common or locally abundant residents throughout the western foothills north of the Yosemite region; uncommon or rare farther south; at higher elevations nesting occurs at Lake Almanor, Lake Van Norden (in Placer and Nevada Counties), and other large reservoirs.
East Side. Common to locally abundant residents in suitable habitats; representative nesting areas include Sierra Valley, Honey Lake, Lake Tahoe, Bridgeport Reservoir, Mono Lake, and Owens Valley.
TRENDS AND CONSERVATION STATUS Prior to the early 1970s, resident Canada Goose populations outside of northeastern California were small and localized to a few areas in California, including Butte County (the Oroville area) and some breeding birds in the Bay Area. Some of these may have been the progeny of birds released by the California Department of Fish and Game decades ago or from private breeders or hunting clubs. Once a few pairs become established in urban or suburban settings, where they cannot be hunted, they reproduce at remarkable rates and have done so all across the state and country. Sierra populations reflect this overall trend. Before the mid-1980s, Canada Geese were very rarely recorded on any Sierra Breeding Bird Survey routes. They are now routinely found on nearly a third of those routes, and they are now common breeders in suitable habitats on both sides