Western Birds Journal

Volume 37, No. 3

Published July 1, 2006

Issue description

Volume 37, number 3 of Western Birds, published 2006

Articles

  1. Cover image V37(3)

    TAMIKO D. RUHLEN, GARY W. PAGE, LYNNE E. STENZEL (Author)

    EFFECTS OF A CHANGING ENVIRONMENT ON NESTING SNOWY PLOVERS AT OWENS LAKE, CALIFORNIA

    Fourteen lakeside surveys for breeding Snowy Plovers (Charadrius alexandrinus) have been conducted at Owens Lake over three decades. There was a steep decline from 499 adults on the first survey in 1978 to 195 on the second in 1988. Nine subsequent counts from 1990 to 2001 varied from 101 to 203 adults (mean 138, standard error 11). After the introduction in 2002 of water to large areas for dust control, numbers of adults increased annually to 658 in 2004. Shallow flooded areas now account for 85% of the adults. The distribution of nests has also changed since the addition of water. The area of most extensive shallow flooding accounted for 71% and 61% of the nests found in 2002 and 2003, respectively, compared with only 27% in the area in 2001 prior to flooding. The nesting season has also been extended by about a month since the plovers began nesting in flooded areas. At Owens Lake Snowy Plovers have benefited from the shallow flooding for dust control but are now more dependent on man-made habitat.

  2. Cover image V37(3)

    SPENCER G. SEALY (Author)

    A HISTORICAL PERSPECTIVE ON THE CITRUS-LIKE SCENT OF THE CRESTED AUKLET

    The tangerine-like odor produced by breeding Crested Auklets (Aethia cristatella) of both sexes has attracted considerable attention recently as researchers attempt to determine its function. Chicks and one-year-old immatures do not produce the odor. Even though the odor has long been known to the Yu’pik people of St. Lawrence Island, naturalists and ornithologists visiting seabird colonies on the Aleutian Islands and in the Bering Sea from the mid-1700s through first half of the 20th century did not mention the odor. I trace the steps of two early ornithologists, Charles H. Townsend and Ira N. Gabrielson, whose numerous visits to auklet colonies in the late 1800s and 1940s, respectively, provided opportunities to smell the scent. The odor was eventually described on the basis of specimens smelled during preparation and on the basis of encounters with the auklets at sea. The closely related Whiskered Auklet (A. pygmaea) also produces an odor, but its function requires study.

  3. Cover image V37(3)

    DAVID H. ELLIS (Author)

    SWIFT-HUNTING BEHAVIOR OF THE PEREGRINE FALCON IN ARIZONA

    Among the solo and cooperative attacks by Peregrine Falcons (Falco peregrinus) on White-throated Swifts (Aeronautes saxitalis), the most spectacular are long series of declining stoops (sometimes involving elevational changes of up to 1 km). These repeated stoops sometimes result in falcons attempting to strike prey while climbing as well as when diving. An unspectacular technique involves swooping up, stalling, and grasping at swifts coming and going from a cleft in a cliff wall.

  4. Cover image V37(3)

    RYAN L. MATHIS, MARK A. COLWELL, LINDA W. LEEMAN, THOMAS S. LEEMAN (Author)

    LONG-BILLED CURLEW DISTRIBUTIONS IN INTERTIDAL HABITATS: SCALE-DEPENDENT PATTERNS

    Key ecological insights come from understanding a species’ distribution, especially across several spatial scales. We studied the distribution (uniform, random, or aggregated) at low tide of nonbreeding Long-billed Curlew (Numenius americanus) at three spatial scales: within individual territories (1–8 ha), in the Elk River estuary (~50 ha), and across tidal habitats of Humboldt Bay (62 km²), California. During six baywide surveys, 200–300 Long-billed Curlews were aggregated consistently in certain areas and were absent from others, suggesting that foraging habitats varied in quality. In the Elk River estuary, distributions were often (73%) uniform as curlews foraged at low tide, although patterns tended toward random (27%) when more curlews were present during late summer and autumn. Patterns of predominantly uniform distribution across the estuary were a consequence of territoriality. Within territories, eight Long-billed Curlews most often (75%) foraged in a manner that produced a uniform distribution; patterns tended toward random (16%) and aggregated (8%) when individuals moved over larger areas. At each spatial scale, food probably had the strongest influence on distributions, whereas predation played a relatively minor role in determining patterns.

  5. Cover image V37(3)

    MARK J. RAUZON (Author)

    OCCURRENCE OF BRIDLED AND GRAY-BACKED TERNS IN AMERICAN SAMOA

    In the central Pacific, the Bridled Tern (Sterna anaethetus) and the Gray-backed Tern (S. lunata) are best distinguished by the pattern of the undersides of their primaries, largely white in the Gray-backed, contrastingly dark in the Bridled. In American Samoa, where the species’ ranges overlap, their similarity in plumage may have led to confusion in early records of both species. During seabird surveys around Tutuila, American Samoa, in December 2003, I confirmed the presence of the Bridled Tern. I also review past sightings of the Gray-backed Tern in American Samoa.

  6. Cover image V37(3)

    Steve N. G. Howell (Author)

    BOOK REVIEWS: The Shorebird Guide: by Michael O’Brien, Richard Crossley, and Kevin Karlson. 2006. Houghton Mifflin Company. 490 pages, 870 color photos. Paperback $24.95 (ISBN 0-618-43294-9).

    Shorebirds are popular, and three new shorebird identification guides have appeared in the last year or so: this work, Message and Taylor’s Shorebirds of North America, Europe, and Asia (reviewed below), and Paulson’s Shorebirds of North America (reviewed in Western Birds 36:275–276, 2005). You may well ask, “Do we need all of these guides? Which one(s) should I buy?” The answer depends on what you want. Let’s take a look at The Shorebird Guide.

  7. Cover image V37(3)

    Steve N. G. Howell (Author)

    BOOK REVIEWS: Shorebirds of North America, Europe, and Asia: by Stephen Message and Don Taylor. 2005. Princeton University Press. 224 pages, 77 color plates. Paperback $35 (ISBN 0-691-12672-0).

    This work (hereafter Shorebirds) was first published in the U.K. by Helm with the more honest title Waders of Europe, Asia, and North America. At the risk of sounding like a broken record, repeating complaints from some of my past reviews, I must say that the author and artist are not overly familiar with North American species or literature. Yet this has not prevented a commercially oriented make-over of the cover and title. Shorebirds is built around a large number of color plates attractively painted by Message and is intended to aid with field identification. 

  8. Cover image V37(3)

    PETER PYLE (Author)

    FEATURED PHOTO: STAFFELMAUSER AND OTHER ADAPTIVE STRATEGIES FOR WING MOLT IN LARGER BIRDS

    The remiges (primaries and secondaries) of birds take a relatively long time to develop. Growth rates of primaries, for example, can vary from 3.2 mm per day in smaller birds to 6.3 mm per day in larger birds, but the summed lengths of all primaries can be as much as ten times greater in larger birds than in smaller birds (Rohwer 1999). Most passerines and other smaller birds replace all primaries sequentially from the innermost (p1) to the outermost (p9 or p10) and maintain the ability to fly, but most larger birds lack the time (between periods of breeding and migration) to follow this sequence within a single molt and have evolved alternative strategies.

  9. Cover image V37(3)

    Ted Floyd, Catherine Waters, Jay Withgott (Author)

    31ST ANNUAL WFO CONFERENCE, BOULDER, COLORADO: RETROSPECTIVE

    The 31st annual conference of Western Field Ornithologists met with tremendous success. In Boulder, Colorado, 21–24 September 2006, the 114 attendees enjoyed four stimulating days of scientific paper sessions, workshops, panels, field trips, and camaraderie.