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The American Woodcock (Scolopax minor) is one of the earliest ground-nesting birds in the northeastern United States. In Maine, nesting begins in early April when temperatures can drop below freezing and significant snowfall can accumulate. Nests are usually in open woods, where eggs are laid on the ground in a shallow depression (Pettingill 1936, Mendall and Aldous 1943, Sheldon 1967). Peak hatching occurs in early May (Dwyer et al. 1982), when temperatures are cool and precipitation is common. Woodcock chicks are dependent on the female for most of their food for at least seven days after hatching (Gregg 1984). During cool, wet weather, chicks require constant brooding by females; prolonged periods of inclement...
Categories: Publication; Types: Citation; Tags: The Auk
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With a slight change in title, this is the second edition of Edwards' (1974) Coded List, from which it differs significantly. First, it covers only nonpasserines instead of all the birds of the world; presumably a list of the passerines will follow soon. The code is different, the format is expanded, and the information content is greater (3,798 species are listed as opposed to 3,656). This edition is clearly a new entry in the world-list field.
Categories: Publication; Types: Citation; Tags: The Auk
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Sperm-storage glands were found in the uterovaginal (UV) region of the oviduct in Northern Fulmars (Fulmarus glacialis), Horned Puffins (Fratercula corniculata), and Leach's Storm-Petrels (Oceanodroma leucorhoa) collected before or shortly after egg laying. Previously described only in domestic Galliformes, UV sperm-storage glands may prove to be a common feature of the avian reproductive system. There is as yet no compelling explanation of their function in the Horned Puffin. In the Northern Fulmar, and probably in other petrels, however, sperm-storage glands allow the separation of the male and female over pelagic waters for several weeks immediately before egg laying. The likelihood of prolonged viability of...
Categories: Publication; Types: Citation; Tags: The Auk
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Beak abnormalities are rare among adult birds and, typically, are not widespread in a given population, within a region, or across multiple species. A high concentration of beak deformities was recently documented in Black-capped Chickadees (Poecile atricapillus) and other resident avian species in Alaska. We describe a parallel condition in Northwestern Crows (Corvus caurinus) that signals the emergence of a multispecies epizootic. On the basis of 186 Northwestern Crows captured at six sites in Alaska during 2007 and 2008, we estimated the prevalence of beak deformities in adults to be 16.9 ± 5.3%, the highest rate of gross deformities ever recorded in a wild bird population. Prevalence varied among sites and was...
Categories: Publication; Types: Citation; Tags: The Auk
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The ability to successfully colonize and persist in diverse environments likely requires broad morphological and behavioral plasticity and adaptability, and this may partly explain why the Peregrine Falcon (Falco peregrinus) exhibits a large range of morphological characteristics across their global distribution. Regional and local differences within Peregrine Falcons were sufficiently variable that ∼75 subspecies have been described; many were subsumed, and currently 19 are generally recognized. We used sequence information from the control region of the mitochondrial genome to test for concordance between genetic structure and representatives of 12 current subspecies and from two areas where subspecies distributions...
Categories: Publication; Types: Citation; Tags: The Auk
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The Dusky Canada Goose (Branta canadensis occidentalis) population that breeds in the Copper River Delta, Alaska, has declined substantially since the late 1970s. Persistent low numbers have been attributed to low productivity in recent years. We examined patterns in survival rates of 1,852 nests to better understand ecological processes that influenced productivity during 1997-2000. We compared 10 nonparametric models of daily survival rate of nests (DSR) that included variation among years, calendar dates, nest initiation dates, and nest ages with equivalent models based on parametric functions. The unequivocal best model included patterns of DSR that varied among discrete periods of years, calendar dates, and...
Categories: Publication; Types: Citation; Tags: The Auk
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Wild hybrid birds are always of interest with regard to our understanding of the variation encountered in nature. They may also be of ore or less taxonomic significance, depending on the frequency of their occurrence and other factors. We herein report and describe an apparent hybrid Northern Waterthrush (Seiurus noveboracensis) x Blackpoll Warbler (Dendroica striata) taken by Robbins at Ocean City, Maryland, on 17 September 1965. The bird (U.S. National Museum, no. 481595), an immature male with no fat, weighed 13.7 g and had apparently normal testes, each measuring 2.0 x 0.5 mm. The hybrid was taken in a net situated close to the ground, inland from the beach north of Ocean City; both Northern Waterthrushes and...
Categories: Publication; Types: Citation; Tags: The Auk
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WHILE working on habitat studies of the Ruffed Grouse (Bonasa umbellus) in the George Washington National Forest during the late spring and early summer of 1941, the author found it possible to carry out a supplemental study on the relative abundance of the breeding birds of the area. Since considerable time was spent in traversing certain sections of the forest in search of Ruffed Grouse broods, an unusual opportunity was afforded to make a general comparative census of the species of birds found therein.
Categories: Publication; Types: Citation; Tags: The Auk
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he 1942 warbler migration at Kenmare, Ward County, North Dakota, was rich in species (seventeen) for a locality so far west on the Great Plains. On June 1, near the end of the northward flight, I found a male Hooded Warbler singing in shrubby undergrowth on a wooded coulee slope on the Des Lacs National Wildlife Refuge, about two miles south of Kenmare. The bird was observed at close range for several minutes, both without and with 7-power binoculars. It behaved as in the vicinity of Washington, D. C., where I have been familiar with the species for several years, the song being vigorous and loud and the movements leisurely.
Categories: Publication; Types: Citation; Tags: The Auk
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Over the past decade, bird conservation activities have become the preeminent natural resource conservation effort in North America. Maturation of the North American Waterfowl Management Plan (NAWMP), establishment of Partners in Flight (PIF), and creation of comprehensive colonial waterbird and shorebird conservation plans have stimulated unprecedented interest in, and funding for, bird conservation in the United States, Canada, Mexico, and other countries in the western hemisphere. Key to that success in the United States has been active collaboration among federal, state and local governments, conservation organizations, academia, and industry. The U.S. Department of the Interior (DOI), which has primary statutory...
Categories: Publication; Types: Citation; Tags: The Auk
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Breeding-season productivity (the per capita number of offspring surviving to the end of the breeding season) is seldom estimated for multibrooded songbirds because of cost and logistical constraints. However, this parameter is critical for predictions of population growth rates and comparisons of seasonal productivity across geographic or temporal scales. We constructed a dynamic, stochastic, individual-based model of breeding-season productivity using demographic data from Wood Thrushes (Hylocichla mustelina) in central Georgia from 1993 to 1996. The model predicts breeding-season productivity as a function of adult survival, juvenile survival, nesting success, season length, renesting interval, and juvenile-care...
Categories: Publication; Types: Citation; Tags: The Auk
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We studied assemblages of feeding shorebirds in three intertidal habitats on the coast of New Jersey during August to document how species segregate spatially both among and within habitats and to determine the effects of tidal cycles on these patterns. The habitats were a sandy beach facing the ocean proper (outer beach), a sandy beach on the mainland side of a barrier island (inner beach), and a small mudflat adjacent to a Spartina alterniflora salt marsh. We were able to identify several microhabitats on the outer beach and mudflat. Most species fed in more than one habitat, but only two, Charadrius semipalmatus and Calidris canutus, used all three habitats regularly. Within habitats, most species exhibited strong...
Categories: Publication; Types: Citation; Tags: The Auk
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This is the 11th supplement since publication of the seventh edition of the Check-list of North American Birds (American Ornithologists' Union AOU 1998). It summarizes decisions made between 1 April 2010 and 15 April 2011 by the AOU's Committee on Classification and Nomenclature-North and Middle America. The Committee has continued to operate in the manner outlined in the 42nd Supplement (AOU 2000). There were no changes to committee membership in 2010.
Categories: Publication; Types: Citation; Tags: The Auk
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We documented patterns of nectar availability and nectarivorous bird abundance over ~3 years at nine study sites across an 1,800-m elevational gradient on Hawaii Island to investigate the relationship between resource variation and bird abundance. Flower density (flowers ha-1) and nectar energy content were measured across the gradient for the monodominant 'Ōhi'a (Metrosideros polymorpha). Four nectarivorous bird species were captured monthly in mist nets and surveyed quarterly with point-transect distance sampling at each site to examine patterns of density and relative abundance. Flowering peaks were associated with season but not rainfall or elevation. Bird densities peaked in the winter and spring of each year...
Categories: Publication; Types: Citation; Tags: The Auk
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On 20 May 1961 an immature female tiger shark (Galeocerdo cuvier), 2.3 meters in length and weighing 52 kg, was caught in the Gulf of Mexico several miles offshore from Sarasota, Florida, by personnel of the Cape Haze Marine Laboratory. The contents of its stomach included a leg and some feathers of a land bird. The leg was sent to the Bird and Mammal Laboratories, Bureau of Sport Fisheries and Wildlife, Washington, D.C., where it was identified by Mrs. R. C. Laybourne as that of a Yellow-billed Cuckoo (Coccyzus americanus). In addition to this bird, the stomach contained a blue crab, several sea catfishes (Galeichthys felis), and part of a black nose shark (Carcharhinus acronatus).
Categories: Publication; Types: Citation; Tags: The Auk
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This is the seventh Supplement since the publication of the 7th edition of the Check-list of North American Birds (American Ornithologists’ Union [AOU] 1998). It summarizes decisions made by the AOU’s Committee on Classification and Nomenclature-North America between 1 January and 31 December 2006.
Categories: Publication; Types: Citation; Tags: The Auk
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Lek-mating Long-tailed Manakins (Chiroxiphia linearis) exhibit an unusual pattern of delayed plumage maturation. Each year, males progress through a series of predefinitive plumages before attaining definitive plumage in their fifth calendar year. Females also exhibit variation in plumage coloration, with some females displaying male-like plumage characteristics. Using data from mist-net captures in northwest Costa Rica (n = 1,315) and museum specimens from throughout the range of Long-tailed Manakins (n = 585), we documented the plumage sequence progression of males, explored variation in female plumage, and described the timing of molt in this species. Males progressed through a series of age-specific predefinitive...
Categories: Publication; Types: Citation; Tags: The Auk
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Since publication of our report on the avian collections in the United States and Canada (Banks, Clench, and Barlow 1973, Auk 90: 136- 170) several changes and additions have come to our attention. In some cases, recent curatorial work has resulted in more accurate counts to replace previous estimates. Other collections have grown markedly in the last few years. Some important private or institutional collections have been transferred to other jurisdictions. Finally, we have received a few completely new reports from collections that were unknown to us or that were unresponsive to our original requests for information.
Categories: Publication; Types: Citation; Tags: The Auk
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In a recent paper published in The Auk, Smith et al. (2009) raised serious concerns over an apparent lack of reproducibility in their study of stable hydrogen isotope values (δDf ) in raptor feathers. The authors based their concerns on results obtained from different laboratories to which they submitted original and blind “repeats” over a multiyear period. A regression of the original sample δD versus “repeat” measurements showed an increase in the magnitude of residuals with increasing δDf , especially for values greater than about −80‰ (Smith et al. 2009: fig. 2). Because of this, the authors “caution against the continued use of δDf for predicting geographic origin, and for addressing important conservation...
Categories: Publication; Types: Citation; Tags: The Auk
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In geese, growth regulates survival in the first year. We examined whether early growth, which is primarily governed by environmental conditions, also affects the probability that individuals that survive their first year enter the breeding population. We used logistic regression on a sample of Black Brant (Branta bernicla nigricans) that were weighed at a known age in their first summer and observed during winter (indicating that they had survived the principal mortality period in their first year) to study whether early growth influenced the probability that those individuals would be recruited into the breeding population. We also examined the effects of cohort (1986-1996), sex, age when measured, and area where...
Categories: Publication; Types: Citation; Tags: The Auk


map background search result map search result map Beak deformities in Northwestern Crows: Evidence of a multispecies epizootic Genetic relationships among some subspecies of the Peregrine Falcon (<i>Falco peregrinus</i> L.), inferred from mitochondrial DNA control-region sequences Beak deformities in Northwestern Crows: Evidence of a multispecies epizootic Genetic relationships among some subspecies of the Peregrine Falcon (<i>Falco peregrinus</i> L.), inferred from mitochondrial DNA control-region sequences