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Animal coloration serves many biological functions and must therefore balance potentially competing selective pressures. For example, many animals have camouflage in which coloration matches the visual background that predators scan for prey. However, different colors reflect different amounts of solar radiation and may therefore have thermoregulatory implications as well. In this study, we examined geographic variation in dorsal patterning, coloration, and solar reflectance among horned larks (Eremophila alpestris) of the western United States. We found that plumage brightness was positively associated with soil granularity, aridity, and temperature. Plumage redness—both in terms of saturation (i.e., chroma) and hue—was positively associated with soil redness and temperature, while plumage patterning was positively associated with soil granularity. Together, these plumage-environment associations support both background matching and Gloger's rule, a widespread ecogeographic pattern in animal coloration. We also constructed thermoregulatory models that estimated cooling benefits provided by solar reflectance profiles of the dorsal plumage of each specimen based on the collection site. We found increased cooling benefits in hotter, more arid environments. Finally, cooling benefits were positively associated with residual brightness, such that individuals that were brighter than expected based on environmental conditions also had higher cooling benefits, suggesting a trade-off between camouflage and thermoregulation. Together, these data suggest that natural selection has balanced camouflage and thermoregulation in horned larks, and they illustrate how multiple competing evolutionary pressures may interact to shape geographic variation in adaptive phenotypes. [ABSTRACT FROM AUTHOR]

I examined images of over 6,300 individual hummingbirds from the Cornell Lab of Ornithology's Macaulay Library to clarify conflicting reports on molt and plumage strategies in 8 species that breed or have bred primarily in the southwestern United States. Fixed replacement sequences from 2 nodes among primaries and 2 nodes among secondaries were found without exception, conforming to the findings of previous studies. I concluded that the preformative molt varied from limited to partial in 3 species, partial to incomplete in 3 species, partial to complete in 1 species, and complete in 1 species. Results of this study clarify molt terminology in Trochilidae as based on evolutionary homologies, and they establish new criteria for age determinations. The Macaulay Library clearly provides an important resource for the investigation of avian molts and plumages. I present a road map for such studies and suggest many other questions on avian molt that can also be investigated. I encourage contributors to the Macaulay Library to take and upload images of birds in molt or in worn plumages. [ABSTRACT FROM AUTHOR]

This paper investigated the oil–gasoline price relationship in the UK and USA following the 2007–2008 global financial crisis. The dummy variable approach to testing for structural break and the nonlinear autoregressive distributed lag approach for modeling asymmetry cointegrating relationships were used. The findings indicate that the crisis induced significant structural break in this relationship in both countries. For the UK, we find strong evidence of rockets and feathers effect plus the possibility of firms using the tax system to hide rent-seeking behavior before and after the crisis, which means that the results of Greenwood-Nimmo and Shin (Econ Lett 121:411–416, 2013) are no longer plausible. For the USA, we find significant evidence of the rockets and feathers effect in the post-crisis period when the data are restricted to March 2013; however, this effect disappears once the data are extended to June 2017. These findings suggest that continuous monitoring and other antitrust and consumer welfare policies are required in these economies to preserve competition and the overall social welfare. [ABSTRACT FROM AUTHOR]

Youth mentoring practitioners and researchers have shown a growing interest in determining the ways in which mentor–youth matching practices might influence the duration and effectiveness of mentoring relationships. The current project tested whether mentor–youth similarities at baseline, in terms of demographic variables and interests in certain activities (e.g., sports, art), predicted a longer duration of mentoring relationships. Analyses used baseline and follow‐up data from over 9,000 youth who participated in community‐based mentoring programs in the northeastern United States, as well as their volunteer mentors. Racial and ethnic similarity between mentor and youth was predictive of longer match duration. Moreover, a shared dislike of activities was associated with longer matches than either shared interests or discordant interests in activities. Findings have important implications for determining the ways in which mentor–youth matching practices influence the length and effectiveness of mentoring relationships. [ABSTRACT FROM AUTHOR]

Copyright of Avian Diseases is the property of American Association of Avian Pathologists, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Evidence from bones, artifacts, and imagery demonstrates the importance of scarlet macaws in Southwest/Northwest sites from around A.D. 700 to today. Archaeologists interpret these birds as indicators of exchange, ritual, and social complexity. These varied interpretations are questioned based on the life cycle of the macaw and issues with aging archaeological specimens. Ethnographic and documentary data provide comparative material for archaeological macaws. Use of macaws, their skins, and feathers reflects a widespread and apparently stable set of practices with implications for interaction, beliefs, and politics. [ABSTRACT FROM AUTHOR]

Documentamos dos tipos de plumajes melánicos aberrantes, pálido y oscuro, en tres individuos de Accipiter cooperii en estado silvestre. Capturamos y fotografiamos dos individuos de A. cooperii con plumaje pálido en Dakota del Norte y un individuo de la misma especie en Virginia. Este es el primer estudio de muda de un individuo de A. cooperii de un plumaje aberrante juvenil pálido a un segundo plumaje básico pálido. Además, una de las dos crías macho presenta un plumaje pálido como su madre, lo que sugiere que la aberración es heredable. También describimos el primer plumaje melánico oscuro para A. cooperii. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Abstract: Mercury is a potent neurotoxin affecting birds and other wildlife worldwide. Bald eagles (Haliaeetus leucocephalus) are vulnerable to mercury bioaccumulation because they are high in the food web and associated with aquatic ecosystems prone to mercury methylation. Eagle populations, long endangered in the continental United States by contaminants and persecution, are recovering throughout their range. We used single adult eagle feathers collected near 83 occupied nests to show that mercury levels in the Chesapeake Bay eagle population are the lowest in North America (3.82±5.15μg/g dry weight). We then used 20 feathers from each of 20 salvaged eagles to calculate a confidence interval around the estimate based on single feathers from nesting eagles. Using an inexpensive and non-invasive method to assess mercury burdens we have demonstrated that few Chesapeake Bay bald eagles were above levels suspected of causing reproductive or survival effects in birds. [Copyright &y& Elsevier]

Investigation of the light sensitivity of feathers used in Californian material culture revealed that the cultural values held by these materials was crucial for their interpretation. It was evident that feathers are valued both for their tangible and intangible attributes and that tangible qualities, including color and shape, and modification and attachment methods, often have meaning beyond their decorative and practical functions. Several different feather-working cultures, the birds that are important to these communities, how feathers from these birds are used to make featherwork, and how objects reveal changes in tradition over time are examined. Much of this information requires reference to a combination of sources, including historical and contemporary accounts, discussions with native featherworkers, ethnologists and ornithologists, and close examination of feathered objects in museum collections. This multidisciplinary approach leads to a more thorough understanding of feathered objects and aids conservators in better interpreting whether modifications are the result of access to feathers, intentional alterations of cultural use, or museum display. [ABSTRACT FROM AUTHOR]

The article provides information on a raptor in sub-adult plumage which represents the genus Buteogallus, which is believed to be a Common Black-hawk. It provides tips for separation of the U.S. breeding Common Black-hawk from the Central American breeding Greater Black-hawk. It discusses the distribution and range expansion of the Common Black-hawk along riparian corridors of the southwestern U.S. with close attention to northeastern New Mexico.

We used principal coordinates analysis to analyze variation in 11 plumage characteristics of 1,722 Savannah Sparrows (Passerculus sandwichensis) breeding at 55 different sites from throughout the species range in Canada, Mexico, and the United States. There is clinal interpopulational variation in size with considerable overlap among localities. Savannah Sparrows resident along the Pacific coast of southern California and Baja California, and those from along the coast of Sinaloa and Sonora (i.e., saltmarsh Savannah Sparrows) differ from those throughout the rest of their range (i.e., non-saltmarsh). Variation among populations of non-saltmarsh Savannah Sparrows was clinal with the exception of those from Sable Island, Nova Scotia, which are consistently more pallid than birds from the adjacent mainland. Western Savannah Sparrows are more pallid than those in the east. The median crown stripe of eastern Savannah Sparrows is distinct, whereas the median crown stripe of western Savannah Sparrows generally is indistinct or narrow. Savannah Sparrows, with the exception of those on Sable Island, are also more pallid in relatively hot and dry areas than in cool mesic sites, following the general prediction of Gloger's Rule. There is clinal variation of saltmarsh populations along the Pacific coast with those in the north being relatively dark in coloration, and with more yellow in the supercilium than those farther south. There is also clinal variation among the populations from the east coast of the Gulf of California with pallid birds in the north, where vegetation is sparse, and darker birds to the south: these coastal birds have indistinct median crown stripes and little yellow in the supercilium. [ABSTRACT FROM AUTHOR]

Three to four billion pounds of chicken feathers are wasted in the United States annually. These feathers pose an environmental challenge. In order to find a commercial application of these otherwise wasted feathers, composites have been prepared from feathers. Flexural, impact resistance, and sound dampening properties of composites from chicken feather fiber (FF) and High Density Polyethylene/Polypropylene (HDPE/PP) fiber have been investigated and compared with pulverized chicken quill-HDPE/PP, and jute-HDPE/PP composites. Sound dampening by FF composites was 125% higher than jute and similar to quill although mechanical properties were inferior to the latter two. In ground form, FF and jute composite properties were similar except for 34% higher modulus of jute; under the same formulation and processing conditions, ground FF composites had nearly 50% lower mechanical properties compared with ground quill composites. It was found that voids and density of composites have effect on mechanical and sound dampening properties; however, no direct relationship was found between mechanical properties and sound dampening. [ABSTRACT FROM AUTHOR]

Despite a large body of research concerning mercury (Hg) in birds, no single tissue has been used consistently to assess Hg exposure, and this has hampered comparisons across studies. We evaluated the relationships of Hg concentrations among tissues in four species of waterbirds (American avocets [Recurvirostra americana], black-necked stilts [Himantopus mexicanus], Caspian terns [Hydroprogne caspia; formerly Sterna caspia], and Forster's terns [Sterna forsteri]) and across three life stages (prebreeding adults, breeding adults, and chicks) in San Francisco Bay, California, USA. Across species and life stages, Hg concentrations (least square mean ± standard error) were highest in head feathers (6.45 ± 0.31 µg/g dry wt) and breast feathers (5.76 ± 0.28 µg/g dry wt), followed by kidney (4.54 ± 0.22 µg/g dry wt), liver (4.43 ± 0.21 µg/g dry wt), blood (3.10 ± 0.15 µg/g dry wt), and muscle (1.67 ± 0.08 µg/g dry wt). Relative Hg distribution among tissues, however, differed by species and life stage. Mercury concentrations were highly correlated among internal tissues (r² ≥ 0.89). Conversely, the relationships between Hg in feathers and internal tissues were substantially weaker (r² ± 0.42). Regression slopes sometimes differed among species and life stages, indicating that care must be used when predicting Hg concentrations in one tissue based on those in another. However, we found good agreement between predictions made using a general tissue-prediction equation and more specific equations developed for each species and life stage. Finally, our results suggest that blood is an excellent, nonlethal predictor of Hg concentrations in internal tissues but that feathers are relatively poor indicators of Hg concentrations in internal tissues. [ABSTRACT FROM AUTHOR]

In 2000, 2001, and 2002, blood and feather samples were collected from 40–45-day-old nestling ospreys ( Pandion haliaetus) from Chesapeake Bay and Delaware Bay and River. Concentrations of 18 metals, metalloids, and other elements were determined in these samples by inductively coupled plasma-mass spectroscopy, and Hg concentrations were measured by cold vapor atomic absorption spectroscopy. When compared to concurrent reference areas (South, West, and Rhode Rivers), mean As and Hg concentrations in blood were greater ( p < 0.05) in two of three Chesapeake Bay regions of concern (Baltimore Harbor [As: 1.18 vs. 0.548 μg/g dw], Anacostia River [Hg: 0.305 vs. 0.178 μg/g dw], and Elizabeth River [As: 0.876 vs. 0.663 μg/g dw; Hg: 0.260 vs. 0.180 μg/g dw]). Lead was detected more frequently in blood of nestlings from the highly industrialized Elizabeth River compared to the rural reference area. When compared to the concurrent reference area, mean Al, Ba, Hg, Mn, and Pb concentrations in feathers were substantially greater ( p < 0.05) in one or more Chesapeake regions of concern (Anacostia River [Al: 206 vs. 62.1 μg/g dw; Ba: 3.31 vs. 0.823 μg/g dw; Mn: 65.4 vs. 22.9 μg/g dw] and Elizabeth River [Al: 165 vs. 63.5 μg/g dw; Hg: 1.24 vs. 0.599 μg/g dw; Pb 1.47 vs. 0.543 μg/g dw]). When compared to the coastal Inland Bays reference area, feathers of nestlings from northern Delaware Bay and River had greater concentrations ( p < 0.05) of Ba (1.90 vs. 0.660 μg/g dw), Fe (258 vs. 109 μg/g dw), Mn (18.5 vs. 4.66 μg/g dw), Mo (0.130 vs. 0.040 μg/g dw), Pb (1.96 vs. 0.624 μg/g dw), and V (0.671 vs. 0.325 μg/g dw), presumably due to extensive metal-working and petroleum refinery activities. Concentrations of Hg in nestling feathers from Delaware were frequently greater than in the Chesapeake. The present findings and those of related reproductive studies suggest that concentrations of several heavy metals (e.g., Cd, Hg, Pb) in nestling blood and feathers from Chesapeake and Delaware Bays were below toxicity thresholds and do not seem to be affecting chick survival during the nestling period. [ABSTRACT FROM AUTHOR]

The US Environmental Protection Agency conducts risk assessments of insecticide applications to wild birds using a model that is limited to the dietary route of exposure. However, free-flying birds are also exposed to insecticides via the inhalation and dermal routes. We measured azinphos-methyl residues on the skin plus feathers and the feet of brown-headed cowbirds ( Molothrus ater) in order to quantify dermal exposure to songbirds that entered and inhabited an apple ( Malus x domestica) orchard following an insecticide application. Exposure to azinphos-methyl was measured by sampling birds from an aviary that was built around an apple tree. Birds sampled at 36 h and 7-day post-application were placed in the aviary within 1 h after the application whereas birds exposed for 3 days were released into the aviary 4-day post-application. Residues on vegetation and soil were also measured. Azinphos-methyl residues were detected from the skin plus feathers and the feet from all exposure periods. Our results underscore the importance of incorporating dermal exposure into avian pesticide risk assessments. [ABSTRACT FROM AUTHOR]

Waterfowl managers often attempt to protect local breeding stocks of mallards (Anas platyrhynchos) from hunting pressure, but presently they cannot identify natal origins of birds shot during fall hunting seasons with certainty, unless recovered birds are banded before fledging. Accordingly, we examined whether stable isotope methodology could accurately delineate natal origins of mallards at a fine scale within the upper Midwest (USA).We determined δ13C, δD, and δ15N values from feather samples of 102 flightless mallard ducklings collected in Minnesota, North Dakota, South Dakota, and Wisconsin, USA, from 7 July to 9 September 2002. We detected inverse relationships between latitude and δ13C (R²= 0.223) and δD (R2=0.210). We also detected a weak positive relationship between easterly shifts in longitude and δ13C (R² = 0.067) and a weak negative relationship between easterly shifts in longitude and δ15N (R² = 0.076). The 13C and deuterium values differed (P < 0.02) among states: North Dakota was most depleted in 13C, and South Dakota was least depleted in deuterium. Discriminant function analysis delineated natal origins of mallard ducklings in Minnesota, North Dakota, South Dakota, and Wisconsin with low-to-moderate accuracy (47%), whereas we predicted natal origins of ducklings among subregions (Prairie [ND, SD] vs. Great Lakes [MN, WI] states) with moderate accuracy (72%). We conclude that stable isotope methodology has a limited ability to determine natal origins of migratory birds along a longitudinal corridor at fine scales but that it improves across ecoregions. However, the ability of deuterium to determine natal origins of migratory birds may vary as hydrological conditions, within and among areas, change throughout time. Researchers should account for annual variation in deuterium found in surface waters when investigating natal origins of migratory birds that use food derived primarily from these waters. [ABSTRACT FROM AUTHOR]

Understanding the ecology and evolution of migratory animals requires information on how populations are geographically linked between periods of the annual cycle. To examine whether trace elements could be used to track migratory birds, we analyzed concentrations of 42 trace elements in feathers of western sandpipers (Calidris mauri (Cabanis, 1857)) that were grown at five different wintering sites ranging from San Francisco Bay (USA) to the Bay of Panama. Linear discriminant analysis of 15 elements correctly classified all 26 individuals to their wintering sites, including two sites that were separated by less than 3 km. A randomization procedure confirmed the robustness of these findings. Our analysis suggests that trace elements can be used to assign individuals to specific sites of origin. Although we did not sample feathers from all wintering areas, the regions our sites represented comprised a significant percentage of the global population. However, since trace element profiles appear to be highly specific to geographic sites, we suggest that this technique is best suited for cases where samples can be obtained from the majority of populations throughout a species range. Thus, under certain circumstances, trace element profiles may provide the potential to identify populations with a high degree of spatial accuracy. [ABSTRACT FROM AUTHOR]

Feathers tend to be darkly colored in habitats where relative humidity is high and pale where it is low. We suggest that this correlation, known as Gloger's rule, results, in part, from selection for dark feathers that are more resistant than light feathers to bacterial degradation, which is a severe problem in humid habitats where bacteria thrive and a lesser problem in arid habitats. In May and June 2000-2002 we sampled feather-degrading bacteria (Bacillus licheniformis) from the plumage of Song Sparrows (Melospiza melodia) in southeastern Arizona and northwestern Washington. Under standardized laboratory conditions, feather-degrading bacteria from the plumage of sparrows in the humid Northwest degraded feathers more rapidly and more completely than feather-degrading bacteria from sparrows of the arid Southwest. The differences in feather-degrading bacteria and in relative humidity produce a difference in the intensity of selection, which in turn produces the difference in color described in Gloger's rule. [ABSTRACT FROM AUTHOR]

We examined the timing and intensity of body molt in relation to stage of remige growth for postbreeding adult male Long-tailed Ducks (Clangula hyemalis) oft the coast of northern Alaska. During this period, remige and rectrix feathers are molted simultaneously with body feathers during the prebasic molt, which results in a period of increased energetic and nutritional demands. We collected birds from late July through mid-August and recorded intensity of molt in eight regions: head and neck, back and rump, greater coverts, lesser coverts, flank and sides, breast, belly, and tail. Using nonlinear regression, we estimated the peak intensity and variation for each region in relation to ninth primary length. We found little evidence of molt in the head and neck region. The greater and lesser coverts, and back and rump reached peak molt intensities earliest and were followed by tail, breast, and belly. Molt intensity in the flank and side region was highly variable and indicated a more prolonged molting pattern in relation to other regions. While body molt occurs simultaneously with wing molt, we found that molt among regions occurred in a staggered pattern. Long-tailed Ducks may employ this staggered molting pattern to minimize the energetic and nutritional requirements of molt. [ABSTRACT FROM AUTHOR]

We microscopically analyzed 101 textile samples representing 89 cataloged artifacts from the Craig Mound, Spiro, Oklahoma, in order to identify feathers used in their manufacture. Downy feather barbs from three species of birds were identified in textile samples: wild turkey (Meleagris gallopavo; n = 66 samples), Canada goose (Branta canadensis, n = 15), and swan (Cygnus, cf. buccinator; n = 4). These are the first swan remains reported from the Spiro site. Feathers from 84 samples were dyed red or black. Although Spiro iconography depicts falcons, eagles, and woodpeckers, none of the textiles examined in this study contain feathers belonging to species from the avian orders Falconiformes and Piciformes. [ABSTRACT FROM AUTHOR]

Discusses the challenges of finding the evolutionary origin of feathers which was the focus of the Society for Integrative and Comparative Biology symposium in Denver, Colorado from January 6 to 10, 1999. Origins of the symposium; Overview of the issues regarding the evolutionary origins of feathers and avian flight; Importance of the symposium in improving the database; Discussion on the possible directions of research.

Presents information on a study which described chick growth and plumage patterns in Hawaiian Stilt, a precocial bird. Comparison between Hawaiian stilt chick and other shorebirds; Estimating age; Comparison of captive and wild chick growth.

Reports on the biomass-based industrial products developed by U.S. Agricultural Research Service scientists. Details of an absorbent product; Information on a material from starch that could be used to make biodegradable packing peanuts; Development of high-value fibers from chicken feathers.

Spotted owls (SOs, Strix occidentalis) are a flagship species inhabiting old-growth forests in western North America. In recent decades, their populations have declined due to ongoing reductions in suitable habitat caused by logging, wildfires, and competition with the congeneric barred owl (BO, Strix varia). The northern spotted owl (S. o. caurina) has been listed as "threatened" under the Endangered Species Act since 1990. Here, we use an updated SO genome assembly along with 51 high-coverage whole-genome sequences to examine population structure, hybridization, and recent changes in population size in SO and BO. We found that potential hybrids identified from intermediate plumage morphology were a mixture of pure BO, F1 hybrids, and F1 × BO backcrosses. Also, although SO underwent a population bottleneck around the time of the Pleistocene-Holocene transition, their population sizes rebounded and show no evidence of any historical (i.e., 100-10,000 years ago) population decline. This suggests that the current decrease in SO abundance is due to events in the past century. Finally, we estimate that western and eastern BOs have been genetically separated for thousands of years, instead of the previously assumed recent (i.e., <150 years) divergence. Although this result is surprising, it is unclear where the ancestors of western BO lived after the separation. In particular, although BO may have colonized western North America much earlier than the first recorded observations, it is also possible that the estimated divergence time reflects unsampled BO population structure within central or eastern North America., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)

Focuses on the creation of bird preservers as part of the administration policy for conservation of the natural resources by proclamation of the President of the U.S. Creation of the preservers to prevent all shooting of song and plumage birds and to regulate the shooting of game birds for the market; Impact of demands of fashion for plumage on birds; Cost incurred by farmers from the slaughter of wild geese and other fowls which live upon worms and insects.

The article reports on the study regarding the usefulness of chicken feathers as a way of dress accessories for ethical fashionistas in the U.S. According to Australian scientists, clothes and other products of regenerated textiles based on proteins from agricultural waste or byproducts would look and feel like traditional fibers such as wool and silk. However, unlike fibres from petrochemicals such as polyester and nylon, these products would be renewable and biodegradable when composted.

Presents an update on several issues concerning agricultural research in the U.S. as of January 2005. Information on fiber filters made from chicken feathers; Details of the discovery of a genus of gram-positive bacteria from pig manure; Results of a study on the amount of calories and fats consumed by people who frequently eat in fast-food chains.