RODNEY B. SIEGEL, ROBERT L. WILKERSON, JAMES F. SARACCO, ZACHARY L. STEEL (Author)

ELEVATION RANGES OF BIRDS ON THE SIERRA NEVADA'S WEST SLOPE

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Published estimates of elevation ranges of Sierra Nevada birds are based primarily on anecdotal observations and professional opinion rather than systematic surveys. Continuing climate change is likely to alter the elevation ranges of Sierra bird species, and is perhaps already doing so, but published data are inadequate for describing elevation ranges rigorously. We present elevation ranges of 75 common Sierra Nevada birds based on data from Sequoia and Kings Canyon national parks in the southern Sierra Nevada and Yosemite National Park in the central Sierra Nevada. The mean elevation of a species was significantly higher at Sequoia/Kings Canyon than at Yosemite, by an average of 103 m. When we excluded species restricted to low-elevation habitats that are better represented at Sequoia/Kings Canyon than at Yosemite, and species that disperse upslope and we detected well above their likely breeding ranges, the mean difference between the two areas in the mean elevation of the remaining 59 species was even greater, 219 m. These descriptions of elevation ranges will facilitate future assessments of range shifts, and, more immediately, will provide managers of more intensively managed lands in the Sierra Nevada outside the parks with reference information from the relatively pristine parks.

KENNETH L. WEAVER (Author)

AN OUTPOST FOR DESERT BIRDS ON THE COASTAL SLOPE OF SOUTHERN CALIFORNIA

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Aguanga, California, is located on the Pacific slope of Riverside County and has no direct connection to the Colorado Desert. However, isolated populations of birds associated with the desert occur in the arid shrublands surrounding this small community. Even more unexpectedly, three of these desert species coexist with closely related counterparts on the coastal slope: Gambel’s Quail (Callipepla gambelii) occurs with the California Quail (C. californica), the Ladder-backed Woodpecker (Picoides scalaris) occurs with Nuttall’s Woodpecker (P. nuttallii), and the Black-tailed Gnatcatcher (Polioptila melanura) occurs with the California Gnatcatcher (P. californica). My observations near Aguanga document range extensions for a number of species in an area that has received little ornithological attention.

ANNIE E. SCHMIDT, PETE WARZYBOK (Author)

FIRST RECORD OF THE BRIDLED MORPH OF THE COMMON MURRE IN THE PACIFIC

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The Common Murre (Uria aalge) is one of the most numerous marine birds in the Northern Hemisphere (Ainley et al. 2002), widely distributed in both the Atlantic and Pacific oceans. In the Atlantic, breeding colonies range from eastern Canada to Iceland, the British Isles, and Norway. In the Pacific, the species breeds in the Gulf of Alaska, Bering Sea, Sea of Okhotsk, and down the west coast of North America into California (Gaston et al. 1998). Northern populations tend to move south in the winter and are generally restricted to waters of the continental shelf (Gaston et al. 1998).

SCOTT McCONNELL (Author)

MERLIN CHASES PASSERINES FLUSHED BY NORTHERN HARRIER

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On 27 October 2009, 25 km east of Chugwater, Platte County, Wyoming, I spotted a male Northern Harrier (Circus cyaneus) approximately 900 m away hunting at a height of 1–2 m over a pasture. As it flew, the harrier frequently flushed passerine birds, which it did not pursue. After approximately 30 seconds, the harrier suddenly turned 180° and flew east at a faster rate of speed. I then noticed a Merlin (Falco columbarius) that had come in from the west and was now close to the harrier. The Merlin began following approximately 5–10 m behind the harrier and using it as a beater, chasing the passerines being flushed by the larger raptor, which had resumed its slower hunting speed.

DAVID VANDER PLUYM (Author)

BOOK REVIEW: Molt in North American Birds

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A lot of birders know very little about molt, even though for a bird molt is as fundamental a part of the life cycle as breeding. Two recent publications attempt to help one better understand this tricky topic. The goal of Molt in North American Birds is to be an easy-to-read reference explaining the patterns of molt by family. Although the title says “North American,” the book covers molts of only species occurring north of Mexico, though much of the information on families also applies to many Mexican species. Feather-Watching attempts to explain feather terminology and molt in an interactive CD format.

David Vander Pluym (Author)

BOOK REVIEW: Feather-Watching: An Interactive CD Guide for Studying Birds in the Field

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A lot of birders know very little about molt, even though for a bird molt is as  fundamental a part of the life cycle as breeding. Two recent publications attempt to  help one better understand this tricky topic. The goal of Molt in North American  Birds is to be an easy-to-read reference explaining the patterns of molt by family.  Although the title says “North American,” the book covers molts of only species oc curring north of Mexico, though much of the information on families also applies to  many Mexican species. Feather-Watching attempts to explain feather terminology  and molt in an interactive CD format.

LORI HARGROVE (Author)

BOOK REVIEW: Effects of Climate Change on Birds

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The topics of global climate change and its potential effects on species and ecosystems have recently entered a major spotlight of public attention. Research in these areas has also recently surged. My search of the ISI Web of Science (available at university libraries), with the simple search criteria “birds” and “climate change,” yielded 592 journal articles relating to birds and climate change published in the last 4-year period, 2007–2010, compared to only 32 from 1997 to 2000. Because of the many variable ramifications of climate change and complex interactions, however, it’s exceedingly difficult to link climate change to measurable effects on particular species. Effects of Climate Change on Birds is an edited volume that gives an overview of our current level of knowledge and current research on the biological consequences of climate change on birds. Although the take-home message is that we have much yet to learn, the editors suggest that birds may serve as a useful model for climate-change effects because of the large amounts of historical data, continuing monitoring, and the sensitivity of birds to environmental change. The book attempts to take a synthesis approach with the aim of stimulating future research, and the target audience is the next generation of ornithologists.

ALAN CONTRERAS (Author)

FEATURED PHOTO: HYBRID TOWNSEND’S × YELLOW-RUMPED WARBLERS FROM OREGON AND ARIZONA

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On 6 June 2010 I was birding at the headquarters complex at Malheur National Wildlife Refuge in southeastern Oregon when I noticed what appeared to be a slightly odd-looking Townsend’s Warbler (Dendroica townsendi) in one of the trees. I lost track of the bird and shortly thereafter heard what sounded like a rather plain song of a Yellow-rumped Warbler (D. coronata). A moment later the Townsend’s-like bird came back into view and sang the same song. Townsend’s Warblers have a rather varied sound repertoire, and I have heard them sing shortened or partial songs, but I had never heard one sing a sweet, rich “cheedle cheedle cheedle” like a Yellow-rumped Warbler before.

THANK YOU TO OUR SUPPORTERS

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The board of Western Field Ornithologists and the editorial team of Western Birds thank the following generous contributors who gave to WFO’s publication, scholarship, and general funds in 2010. In addition, we thank and acknowledge those who have contributed in honor of WFO’s late former president Mike San Miguel since the acknowledgment in Western Birds 41(3). The generosity of our members in sustaining WFO is an inspiration to us all.