Volume 35, No. 1

LUKE W. COLE, GUY McCASKIE (Author)

REPORT OF THE CALIFORNIA BIRD RECORDS COMMITTEE: 2002 RECORDS

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The California Bird Records Committee reached decisions on 188 records involving 79 species and one species pair reported in 2002, endorsing 139 of them. New to California was the Eurasian Collared-Dove (Streptopelia decaocto). Adjusted for this addition, California’s bird list stands at 620 species, ten of which, including this addition, are non-native. Potential first state records of the Pink-backed Pelican (Pelecanus rufescens) and Demoseille Crane (Anthropoides virgo) were not accepted on grounds of questionable natural occurrence, and a potential state first Yellow-breasted Bunting (Emberiza elegans) was not accepted on grounds of identification. Other significant records reported here include the return of California’s first Common Greenshank (Tringa nebularia), the state’s second Little Bunting (Emberiza pusilla), third Arctic Warbler (Phylloscopus borealis), and fourth Glossy Ibis (Plegadis falcinellus). In addition to discussing the decisions of the Committee on 2002 records, this report discusses trends in documentation of birds submitted to the Committee.

JULIA I. SMITH, MARK D. REYNOLDS, GRETCHEN LeBUHN (Author)

WARBLING VIREO NESTING ECOLOGY IN THE NORTHERN SIERRA NEVADA

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In California, for unknown reasons, the Warbling Vireo (Vireo gilvus swainsonii) has poor reproductive success, and its numbers have declined over the past 20 years. From June through August 1998 we monitored 70 nests of the Warbling Vireo in a previously unstudied population on the eastern slope of the northern Sierra Nevada. Nests were generally placed 7 m or higher in mature trees, situated at over 50% of the nest-plant’s height, and most often in the periphery of the nest-plant’s foliage. The two most common nest-plant species were the Quaking Aspen (Populus tremuloides, n = 30) and Lodgepole Pine (Pinus contorta, n = 30). Such heavy reliance on a conifer by the Warbling Vireo has not been reported previously. Nest success was not significantly associated with habitat or nest-site characteristics; thus successful sites did not differ dramatically from unsuccessful sites. Most egg dates were concentrated within a single week (2–9 July), and most of the successful nests were in the egg-incubation phase during the first two weeks of July. Eighteen nests fledged at least one Warbling Vireo; one nest fledged a Brown-headed Cowbird (Molothrus ater). Seventy-four percent of nesting attempts failed; most failed nests showed signs of avian rather than mammalian predation. We recommend that vireo conservation efforts in the northern Sierra Nevada focus on increasing the availability of suitable nest sites by promoting mature stands of aspens and pines offering well-concealed nest sites in the periphery of the foliage, limiting forest disturbance in July during the critical nesting period, and minimizing environmental modifications that favor avian nest predators such as Steller’s Jay (Cyanocitta stelleri).

CAROL A. ERWIN, KRISTEN B. ROZELL, LUCAS H. DeCICCO (Author)

NOTES: UPDATE ON THE STATUS AND DISTRIBUTION OF WILSON’S PHALAROPE AND YELLOW-BELLIED SAPSUCKER IN ALASKA

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The Wilson’s Phalarope (Phalaropus tricolor) and the Yellow-bellied Sapsucker (Sphyrapicus varius) are relatively recent additions to Alaska’s avifauna. The first observations of the Wilson’s Phalarope in Alaska were made in 1962, at the Columbia Creek Flats on 20 May (64° 26′ N, 141° 25′ W) (Kessel and Springer 1966) and at Barrow on 9 June (Pitelka 1974). The Yellow-bellied Sapsucker was first observed in Alaska on 16 June 1976, near Northway Junction (Kessel 1986). Kessel and Gibson (1994) suggested a northwestward range expansion for the Wilson’s Phalarope into Alaska, and we support that conclusion by reporting the first documented evidence for breeding of this species in the state. Here we also report on the westernmost breeding and occurrence records for the Yellow-bellied Sapsucker and suggest a continental westward range expansion for this species.

LAINE MacTAGUE (Author)

NOTES: BAT PREDATION BY THE ACORN WOODPECKER

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In July 2001 I observed predation on a bat (species unidentified) by an Acorn Woodpecker (Melanerpes formicivorus) at the Hopland Research and Extension Center in Mendocino County, California.

A population of Acorn Woodpeckers inhabits the small developed portion of the station along Parson’s Creek, nesting in the large oaks. On 15 July 2001, Zebulon Young directed my attention to a hole in the door of a barn. The hole was approximately 5 cm in diameter and 2.5 m from the ground, in an area shaded by oaks most of the day. The door is made of two-by-four framework covered on both sides with plywood; the hole went through only the exterior layer of plywood, providing access to an otherwise sealed area of about 9 cm in width, 40 cm in breadth, and >2 m in depth. Young related that he had seen the woodpecker fly to this hole, reach in, pull out a bat with its beak, and fly with it into an overhanging oak tree. He pointed out the bird, high atop a thick horizontal oak branch. I could just see the head of the woodpecker rapidly appearing and disappearing from sight. The woodpecker appeared to be striking the branch on which it stood with its beak. The tap-tapping sound that usually accompanies this behavior was absent; instead, I heard a repeated call coming from the area of the woodpecker that sounded much like the high-pitched, relatively weak call of a bat. As I watched, several other woodpeckers flew to the immediate area, landing from 4 meters to less than 1 meter away, appearing to watch the activity with great interest. The closest of these engaged in repeated bobbing. Some or all of the woodpeckers were calling. As the struggle continued I eventually saw the flapping wing and a portion of the body of the woodpecker’s prey, a small, dark, struggling bat.

KIMBERLY J. UYEHARA (Author)

NOTES: FIRST RECORD OF THE SORA IN THE STATE OF HAWAII

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The Sora (Porzana carolina) is the most common and widely distributed member of the rail family in North America. It breeds as far north as Alaska and Canada’s Northwest Territories and winters as far south as Guyana and central Peru (AOU 1998, Melvin and Gibbs 1996). Long-distance vagrancy and dispersal to remote lands is widespread in rails (Taylor 1998). This paper reports the first Sora confirmed in the Hawaiian Islands and briefly reviews other records of rails in the islands. While the occurrence of Porzana rails in Hawaii could be expected, on the basis of the fossil record, surprisingly, this report is the first documentation of a vagrant of this genus in the Hawaiian chain.

JAMES A. JOHNSON, STEVEN M. MATSUOKA, DANIEL R. RUTHRAUFF, MICHAEL A. LITZOW, MAKSIM N. DEMENTYEV (Author)

NOTES: ADDITIONS TO THE AVIFAUNA OF ST. MATTHEW ISLAND, BERING SEA

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St. Matthew Island (60° 24′ N, 172° 42′ W) is located in the north-central Bering Sea and is renowned for its distinctive Beringian flora and fauna. Because of its central position between the coasts of Russia and Alaska, St. Matthew Island and its nearby satellites, Hall and Pinnacle islands, support a mixture of Palearctic and Nearctic avifaunas. Of special interest to North American ornithologists are the numerous Eurasian bird species that visit the islands each spring and fall. Winker et al. (2002) published the first comprehensive summary of bird records for the 125 species detected on St. Matthew Island from 1899 to 1997. Because of its remote location, however, St. Matthew Island is seldom visited, and the island’s avifauna remains poorly described.

Diana L. Humple (Author)

BOOK REVIEWS: Ageing North American Landbirds by Molt Limits and Plumage Criteria: A Photographic Companion to the Identification Guide to North American Birds, Part I: by Dan Froehlich. 2003. Slate Creek Press. 51 pages, with 32 color photographs and 2 line drawings. Paperback, $18.50. Available from Institute for Bird Populations (www.birdpop.org/danflyer.htm

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As much as banders were thrilled to discover the wealth of new information published in 1997 by Peter Pyle in the Identification Guide to North American Birds, Part I (hereafter IDG1), many found themselves limited in their ability to use that book to its full capacity. In particular, the use of molt limits (basically, the points of contrast between old and new feathers) was a relatively new concept to most North American banders, among whom there was a general unfamiliarity with how to recognize all but the most obvious molt limits (e.g., on Black-headed Grosbeaks or on Spotted and Eastern towhees). In this photographic companion (hereafter Photographic Companion), Froehlich seeks to provide the visual aids needed to connect what banders see in the hand with what they read in Pyle’s book. He also provides detailed background information on molt patterns as they relate to age-specific plumages, which should increase the readers’ understanding of what she or he sees, both in the photos and in the hand. The Photographic Companion does not provide photographs for every species included in the IDG1, but instead provides photographs of molt-limit patterns using 24 species from throughout North America as examples. As with the IDG1, this is primarily a book for banders, although increasing numbers of field ornithologists are starting to apply “in-hand” age criteria as well.

Steve N. G. Howell (Author)

BOOK REVIEWS: Breeding Birds of Napa County, California, an Illustrated Atlas of Nesting Birds: by Murray Berner, Bill Grummer, Robin Leong, and Mike Rippey. 2003. Napa–Solano Audubon Society, Vallejo, CA. 200 pages, with 2 color endpaper maps, numerous black-and-white maps and drawings. Paperback, $25. Available from Napa–Solano Audubon Society, P. O. Box 5027, Vallejo, CA 94591. ISBN 0-615-12290-6.

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Napa County, a small and largely rural county not far north of San Francisco, is perhaps most famous among the general public for its vineyards. But it is also home to a diverse breeding avifauna, ranging from the Greater Roadrunner and Northern Spotted Owl to the Yellow-billed Magpie and Snowy Plover. With the publication of this important work, we are brought one county closer to having breeding bird atlases available for all nine central California counties that border the San Francisco Bay estuary. Atlases have been published for Marin, Sonoma, and San Mateo counties, and field work has been completed for Alameda, Santa Clara, and San Francisco counties (W. D. Shuford pers. comm.); maps for this last county, and for the work-in-progress Contra Costa county atlas, are available over the World Wide Web. A pilot year of atlasing was conducted in Solano County in 1988, but that county since seems to have slipped through the cracks.

JOSEPH MORLAN, ROBIN E. DAKIN, JIM ROSSO (Author)

FEATURED PHOTO: APPARENT HYBRIDS BETWEEN THE AMERICAN AVOCET AND BLACK-NECKED STILT IN CALIFORNIA

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Birds may hybridize more frequently in captivity than in the wild because natural isolating mechanisms can fail under captive conditions (Sibley 1994). Until recently the only documented hybrid between the American Avocet (Recurvirostra americana) and the Black-necked Stilt (Himantopus mexicanus) was a bird hatched in May 1971 from a known mixed pair held in captivity at the San Francisco Zoo (Principe 1977). We report here three similar apparent hybrids in the wild.

In all cases, the presumed hybrid resembled an American Avocet but showed a dark stripe up the back of the neck, a straighter bill, a dark smudge on the face, and intermediate leg coloration. Also the white patch normally visible on the folded wing of an American Avocet was reduced so that only a narrow strip of white feathers was visible. All three wild hybrids had a fairly straight bill, slightly shorter than that of an American Avocet, with a slight upturn at the tip. In addition, all three birds appeared to have tibias longer than those of a typical American Avocet. This combination of intermediate characters and the similarity of all three wild birds to the known captive hybrid support the hypothesis of hybrid origin rather than coincidental odd mutations. The shorter bill of the captive bird may have been a sex difference. The captive bird was thought to be a male, and males of these species have shorter, straighter bills than do females.