Western Birds Journal

Volume 53, No. 4

Published October 1, 2022

Issue description

Volume 53, number 4 of Western Birds, published 2022

Articles

  1. Cover image V53(4)

    ROBERT H. DAY, G. VERNON BYRD, EDGAR P BAILEY (Author)

    BIRDS OF THE SHUMAGIN ISLANDS, ALASKA

     We studied birds in the Shumagin Islands in 18 of the 37 years from 1970 to 2006 and synthesized all available information on birds of this area. A total of 126 forms of 125 species, including hypothetical species, has been recorded in the Shumagins, of which aquatic birds constitute 67% and terrestrial birds 33%. Overall, 52% of all forms breed, probably breed, or formerly bred; of these, aquatic birds represent 57% and terrestrial birds 43%. The avifauna is heavily weighted toward Nearctic (39% of all forms) and Beringian (32%) forms, followed by Holarctic (21%), Palearctic (6%), and Oceanian (2%) forms; breeding taxa are even more heavily weighted toward Beringian (46%) and Nearctic (40%) forms. The Shumagins have few breeding waterfowl, other freshwater birds, and shorebirds and are not on important flyways for any of these groups, despite lying near important spring and fall
    staging areas on the nearby Alaska Peninsula. The seabird and terrestrial avifaunas are diverse and similar to those in nearby areas, especially the eastern Aleutians. Populations of several seabird species in the Shumagins have declined substantially over the last 40 years. Two terrestrial species, the Pacific Wren (Troglodytes pacificus) and Pine Grosbeak (Pinicola enucleator), have expanded their breeding ranges into this area, and breeding distributions of some terrestrial birds in the outer Shumagins appear to be changing. Changes in range or breeding status have been caused, at least in part, by predation by introduced foxes, overgrazing by introduced cattle degrading already limited habitat, and the introduction of ground squirrels.

  2. Cover image V53(4)

    MARIA LEUNG, DONALD REID (Author)

    NESTING ECOLOGY OF THE BARN SWALLOW ON AGRICULTURAL LANDS IN YUKON

     Since the 1980s, the abundance of the Barn Swallow (Hirundo rustica) in north america, including the far north, has declined. To better understand the species’ biology north of 60° n, near the northern limit of its range, and in a region of expanding agriculture, we studied its nesting ecology on farms in southern Yukon Territory, Canada, in 2019 and 2020. We followed 21 attempted nests in 2019, 20 in 2020, of which 52% and 60%, respectively, were inside buildings with permanently open entrances. other nests were built on the outside of buildings. in both years we inferred successful double brooding by three pairs, which is rarely reported north of 60°n latitude. We found the swallows’ reproductive output to be similar to that at temperate latitudes: first clutches ranged from three to six eggs (mean 4.8 in 2019; 4.2 in 2020); second clutches may have averaged marginally smaller (n = 6). The
    mean number of fledglings per nest was 3.3 in 2019 and 3.0 in 2020. Twenty-one percent of nests failed, either by falling off a vertical substrate or because of predation by deer mice (Peromyscus spp.), Black-billed Magpies (Pica hudsonia), or domestic cats. We also compared the air temperatures at nests, usually near building roofs, to ambient temperatures, finding them on average 1.6°C warmer than temperatures outside buildings. We set out 33 platforms and 20 wooden cups designed for Barn Swallow nesting but over the two years of our study the birds did not use any of them.

  3. Cover image V53(4)

    BRENT CARL HETZLER (Author)

    WINTER SURVEYS FOR MEXICAN SPOTTED OWLS WITH AUDIO RECORDERS

     Monitoring Mexican Spotted Owls (Strix occidentalis lucida) in and near breeding territories during winter has practical value but has not been previously studied by passive techniques, including acoustic recorders. Such information could inform breeding survey strategies as well as identify new breeding pairs. The U.S. Fish and Wildlife Service’s standard survey protocol, entailing four nighttime visits to a site and listening for a response to broadcast calls, has limitations in winter, when nonbreeding owls are less likely to respond and multiple visits may not be possible. Instead, I tested the feasibility of using passive sound-recording equipment to detect the owl in winter, deploying audio recorders at two known nesting sites in northern Arizona over 6 months through winter 2014–2015. As a result, I recorded spontaneous calls during each month of the survey. Paired males and females called to each other in winter, and the variation in frequency of calling through the night paralleled the pattern found in previous studies. My data suggest that automated audio detection provides a reliable tool for continuous, high-resolution, long-term, and cost-effective monitoring of the Mexican Spotted Owl, in both winter and summer.

  4. Cover image V53(4)

    Audrey L. MAYER (Author)

    BOOK REVIEW: Bird Versus Bulldozer

     Under California’s Natural Communities Conservation Planning (NCCP) Act of 1991, local governments have developed and implemented ecosystem-based conservation plans (NCCPs) that build upon aspects of the federal government’s Habitat Conservation Plan (HCP) model. An HCP sets aside and manages natural lands for certain plant and/or wildlife species listed under the federal Endangered Species Act (ESA) and allows for “incidental take” of the species by the landowner. An NCCP expands upon this concept, setting aside large, well-connected tracts of land and managing them for multiple species of listed and otherwise declining species. In Bird Versus Bulldozer, Audrey Mayer evaluates the effectiveness of the NCCP approach to conserving the California Gnatcatcher and other taxa reliant on coastal sage scrub in southern California.

  5. Cover image V53(4)

    RICHARD DAWKINS (Author)

    BOOK REVIEW: Flights of Fancy: Defying Gravity by Design and Evolution

     When evolutionary biologist Richard Dawkins (The Selfish Gene, The Blind Watchmaker, The Extended Phenotype, Climbing Mount Improbable), widely regarded as one of the world’s great thinkers, writes a new book, it is probably worth reading. Flights of Fancy is a book about flight in the broadest sense, movement through the air, escaping gravity to the extent possible. It is not a technical book and lacks aerodynamic equations; all of the principles necessary to understand unpowered and powered flight are presented in an intuitive way that is easy to understand. Birds, the premier living flyers, feature prominently, but Dawkins’ treatment is eclectic, and we meet everything from dandelion seeds to Pegasus, the Roc, Icarus, Leonardo da Vinci’s “ornithopter,” and the Gossamer Albatross. The illustrations by Jana Lenzová are attractive, often whimsical (though generally accurate), and add
    much to the book.