Volume 33, number 2 of Western Birds, published 2002
On 13 comprehensive censuses of the San Francisco–San Pablo Bay estuary and associated wetlands, we counted 325,000–396,000 shorebirds (Charadrii) from mid-August to mid-September (fall) and in November (early winter); 225,000 from late January to February (late winter); and 589,000–932,000 in late April (spring). Twenty-three of the 38 species occurred on all fall, early-winter, and spring counts.
The Alaska breeding population of the Steller's Eider (Polysticta stelleri) occurs as two subpopulations, one on the Arctic coastal plain of northern Alaska, primarily near Barrow, and the other on the Yukon–Kuskokwim Delta of western Alaska. In 1997, the Alaska breeding population was listed under the Endangered Species Act as threatened because the nesting range and population were thought to have decreased substantially. The historical (pre-1970) and recent (1970–present) breeding distribution and abundance of Steller's Eiders, however, are not well known.
The Greater Shearwater (Puffinus gravis) breeds in the southern Atlantic Ocean and disperses after breeding to the North Atlantic. On 3 August 2001, I observed and photographed an unidentified shearwater (Figure 1) in the Gulf of Alaska, about 30 km off the southern coast of Montague Island (59°50'N, 148°00'W). The bird was subsequently identified as a Greater Shearwater. This observation and photographic documentation provide the first Alaska state record (D. Gibson in litt.) and one of very few records for the North Pacific (see Table 1). This is the 464th bird species to be recorded in the state of Alaska.
In a monograph concerning speciation and geographic variation in black-tailed gnatcatchers, Atwood (1988) identified three principal areas of sympatry between the California Gnatcatcher (Polioptila californica) and the Black-tailed Gnatcatcher (P. melanura). The largest of these lies in northeastern Baja California, extending north along the coast of the Gulf of California from approximately 29°N (near Bahía de los Ángeles) to 30°N (near Bahía San Luis Gonzaga) and 30 km inland along the eastern base of the Sierra San Pedro Mártir to approximately 30°50'N, 115°15'W (Arroyo El Cajón). To the northeast, along the gulf coast, only P. melanura is known (Grinnell 1928, Wilbur 1987, Atwood 1988, Howell and Webb 1995).
These days, most birders and ornithologists probably have a pretty good feel for what published breeding bird atlases should look like. After all, the first North American atlas projects were conducted more than a quarter-century ago, with most states and provinces having initiated or completed one or more atlases during the past decade or so. The protocol for North American breeding bird atlases is well established and widely agreed upon, and there are fairly uniform (although not formally codified) standards for publishing any atlas.
The classification of the Yellow-bellied (Sphyrapicus varius), Red-naped (S. nuchalis), and Red-breasted (S. ruber) sapsuckers has confounded ornithologists since the late 1800s, a situation that spurred prodigious field and laboratory research during the past half-century aimed at elucidating relationships between these closely related taxa.