bluuebunny/crossref_metadata_2025_split huggingface dataset:
Territory Switching and Floating in White-Bellied Antbird (Myrmeciza Longipes), A Resident Tropical Passerine in Panama
Authors: Fedy Bradley C. , Stutchbury Bridget J. M. 
Published: September 2019

Abstract
We investigated the yearlong territorial behavior of White-bellied Antbirds (Myrmeciza longipes) in Panama by conducting 17 experimental removals during the nonbreeding season on both sexes. We also monitored the territorial behavior and occupancy of 48 males and 34 females throughout the nonbreeding and breeding seasons. We tested the importance of territory switching, mate advertisement, foray behavior, and role of floaters. In seven of the removal experiments, both members of a pair were radiotagged and tracked throughout the duration of the experiments. It was predicted that widowed birds would attempt to attract a new mate through increased song rate or unique vocalizations; however, that behavior was not observed in White-bellied Antbirds. We documented a weak response in floaters to territorial vacancies and found that territory switching occurs regularly in response to experimental removals and naturally within populations. We found density of birds in an area influences the probability of replacement and is likely a reflection of territory quality given that birds in high-density areas were in better physical condition, spent less time off-territory, and competed more for those territories. Telemetry revealed that individuals made silent extraterritorial forays during the nonbreeding season. Birds could use those forays to assess the quality and status of neighboring territories and to find food during this period when food abundance is low. Several birds were observed to temporarily abandon territorial behavior for periods from 2 to 13 months, a previously undocumented behavior in this type of territorial system.
How do Woodpeckers Extract Grubs With Their Tongues? A Study of The Guadeloupe Woodpecker (Melanerpes Herminieri) in The French West Indies
Authors: Villard Pascal , Cuisin Jacques 
Published: September 2019

Abstract
We held an adult Guadeloupe Woodpecker (Melanerpes herminieri) in captivity for two weeks and documented its tongue movements as it caught grubs placed into holes that had been excavated out of a log. We provide evidence that the Guadeloupe Woodpecker does not spear grubs with its tongue but instead grabs them with the tongue's horny tip, which is barbed and coated with saliva, and pulls them out of the holes.
Structure of an African Red-Billed Hornbill (Tockus Erythrorhynchus Rufirostris and T. E. Damarensis) Hybrid Zone as Revealed by Morphology, Behavior, and Breeding Biology
Authors: Delport Wayne , Kemp Alan C. , Ferguson J. Willem H. 
Published: September 2019

AbstractThe distributions of southern African (Tockus erythrorhynchus rufirostris) and Damaraland (T. e. damarensis) Red-billed Hornbills overlap in northern Namibia. Allopatric populations of the taxa have diagnosable differences in habitat, morphology, vocalizations, and displays. We investigated the structure of the hybrid zone using data from morphology, behavior, and breeding biology. The morphological characteristics—eye color and facial plumage color—were summarized as hybrid index scores, which showed a significant positive regression against distance from southwest to northeast across the hybrid zone. Vocalizations also showed a positive relationship between the first principal component (extracted from 12 call variables) and distance across the hybrid zone. However, there appears to be introgression of a T. e. damarensis call into T. e. rufirostris, but not vice versa. In addition, female T. e. damarensis-male T. e. rufirostris breeding pairs occur more frequently than male T. e. damarensis-female T. e. rufirostris pairs. The asymmetrical call introgression may result either from asymmetry in mating or from genetic control of call inheritance. Finally, heterospecific pairs show lower fitness, in the form of reduced hatching success, even when female fitness attributes are included as covariates. Although we are uncertain whether the Red-billed Hornbill hybrid zone is stable, the apparent biological processes operating within it conform to predictions of both the “mosaic” and the “tension zone” models, because both habitat characteristics and a balance of dispersal and selection appear to determine its structure.
Nutrient Reserves of Lesser Scaup (Aythya Affinis) During Spring Migration in the Mississippi Flyway: A Test of the Spring Condition Hypothesis
Authors: Anteau Michael J. , Afton Alan D. 
Published: September 2019

AbstractThe continental scaup population (Lesser [Aythya affinis] and Greater [A. marila] combined) has declined markedly since 1978. One hypothesis for the population decline states that reproductive success has decreased because female scaup are arriving on breeding areas in poorer body condition than they did historically (i.e. spring condition hypothesis). We tested one aspect of that hypothesis by comparing body mass and nutrient reserves (lipid, protein, and mineral) of Lesser Scaup at four locations (Louisiana, Illinois, Minnesota, and Manitoba) between the 1980s and 2000s. We found that mean body mass and lipid and mineral reserves of females were 80.0, 52.5, and 3.0 g higher, respectively, in the 2000s than in the 1980s in Louisiana; similarly, body mass and lipid and mineral reserves of males were 108.8, 72.5, and 2.5 g higher, respectively. In Illinois, mean body mass and lipid reserves of females were 88.6 and 56.5 g higher, respectively, in the 2000s than in the 1980s; similarly, body mass and lipid and mineral reserves of males were 80.6, 76.0, and 2.7 g higher, respectively. Mean body mass of females were 58.5 and 58.9 g lower in the 2000s than in the 1980s in Minnesota and Manitoba, respectively; mean body mass of males, similarly, were 40.7 g lower in Minnesota. Mean lipid reserves of females in the 2000s were 28.8 and 27.8 g lower than those in the 1980s in Minnesota and Manitoba, respectively. Mean mineral reserves of females in the 2000s were 3.2 g lower than those in the 1980s in Manitoba. Consequently, females arriving to breed in Manitoba in the 2000s had accumulated lipid reserves for 4.1 fewer eggs and mineral reserves for 0.8 fewer eggs than those arriving to breed there in the 1980s. Accordingly, our results are consistent with the spring condition hypothesis and suggest that female body condition has declined, as reflected by decreases in body mass, lipids, and mineral reserves that could cause reductions in reproductive success and ultimately a population decline.
The American Bird Conservancy Guide to the 500 Most Important Bird Areas in the United States
Authors: Cooper Robert J. , Warnell Daniel B. 
Published: September 2019

Abstract
The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists' Union.
Miocene Songbirds and the Composition of the European Passeriform Avifauna
Authors: Manegold Albrecht , Mayr Gerald , Mourer-Chauviré Cécile 
Published: September 2019

Abstract
Songbirds (Passeriformes) occur in the fossil record of the Northern Hemisphere around the early Oligocene. It has recently been suggested that the major passeriform lineages diverged in Gondwana in the mid- to late Cretaceous and that the oscines, which include all extant European songbirds, originated on the Australian continental plate. Suboscines are assumed to have originated in western Gondwana. Although there is an abundant fossil record of songbirds in Europe, few attempts have been made to set those remains in a phylogenetic context. Our examination of fossil songbirds from three middle Miocene localities in Germany and France shows that many lack the derived morphology of the hypotarsus that characterizes extant Eupasseres (a taxon that comprises oscines and suboscines). We assume that these fossil taxa are outside the crown-group of Eupasseres, which indicates the presence of an ancient songbird avifauna in the Miocene of Europe, in addition to the few fossil Eupasseres already described in the literature.
Individual Risk Versus Immediate Reproductive Success: A Basis for Latitudinal Differences in the Adrenocortical Response to Stress in Yellow Warblers (Dendroica Petechia)
Authors: Wilson C. Morgan , Holberton Rebecca L. 
Published: September 2019

AbstractIn many bird species, Arctic-breeding and temperate-zone-breeding populations may have different behavioral and physiological adaptations that reflect trade-offs between immediate survival and reproductive success. Compared with their temperate-zonebreeding counterparts, Arctic breeders face shorter breeding seasons and less predictable environments. As a result, it may be necessary for Arctic breeders to employ immediate life-saving responses (facilitated through an acute adrenocortical response) that might come at the expense of immediate reproductive success. Regardless of latitude, the sexes may also face differences in the trade-off between immediate survivorship and reproductive effort. To investigate those hypotheses, we (1) measured the adrenocortical response of male and female Yellow Warblers (Dendroica petechia) at both ends of a north-south breeding distribution and (2) examined within- and between-sex variation in corticosterone secretion during distinct stages of the breeding season that represent significant differences in parental investment (e.g. incubation and nestling provisioning). As predicted, Arctic-breeding males showed a significantly reduced adrenocortical response during the nestling period (when their parental contribution was highest; mean reduction = 39%), whereas temperate-zone-breeding males showed no significant reduction (mean reduction = 12%). Arctic-breeding and temperate-zone-breeding females did not differ in their adrenocortical responses during incubation and provisioning stages, showed reduced responses when compared with temperate-zone-breeding males, and showed responses similar to those of Arctic-breeding males during the provisioning stage. These data support the hypothesis that, during the breeding season, a reduced adrenocortical response (1) is more likely to occur when the potential for brood loss is greatest and (2) is associated with the degree of parental investment by the sexes. The balance between cost(s) and benefit(s) of the adrenocortical response may vary with the relative risks to survivorship and breeding success, and may vary between populations facing different time and energy constraints.
Bactericidal and Fungicidal Activity of Ant Chemicals on Feather Parasites: An Evaluation of Anting Behavior as a Method of Self-Medication in Songbirds
Authors: Revis Hannah C. , Waller Deborah A. 
Published: September 2019

AbstractSongbirds apply ants to their feathers during anting behavior, possibly as a method of reducing feather parasites. We tested polar and nonpolar ant secretions and pure formic acid for bactericidal and fungicidal effects on microbial ectoparasites of feathers. Microbial inhibition trials were run with the bacteria Bacillus licheniformis (strains OWU 138B and OWU 1432B) and B. subtilis; and with the fungi Chaetomium globosum, Penicillium chrysogenum, and Trichoderma viride. Ant chemicals were derived from Camponotus pennsylvanicus, Pheidole dentata, Aphaenogaster rudis, Crematogaster lineolata, and Lasius flavus worker-caste ants. Although pure formic acid strongly inhibited all bacteria and fungal hyphae tested, concentrations of formic acid found in the bodies of formicine ants did not. Neither hexane ant-chemical extracts nor ant suspensions in deionized water inhibited the microbial species. Consequently, the hypothesis that birds apply ants to control feather parasites was not supported.
The Speciation and Biogeography of Birds
Authors: Zink Robert M. , Jones Andrew W. 
Published: September 2019

Abstract
The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists' Union.
Feeding Ecology of Canada Geese (Branta Canadensis Interior) in Sub-Arctic Inland Tundra During Brood-Rearing
Authors: Cadieux Marie-Christine , Gauthier Gilles , Hughes R. John 
Published: September 2019

AbstractThe diet of adult Canada Geese (Branta canadensis interior) and their goslings was determined during the brood-rearing season in a freshwater tundra habitat using esophageal contents from 25 adult females, 27 adult males, and 59 goslings. Habitat use by geese and the availability and quality of aboveground biomass in wet sedge meadows and around ponds in lichen-heath tundra were also evaluated throughout the summer. During the first four weeks of brood-rearing, adult Canada Geese ate primarily graminoids (>65%), especially leaves of the short form of Carex aquatilis and Eriophorum spp., which had the highest nitrogen concentration (2.5–3.5%). Although graminoids were also important for goslings, they consumed a greater variety of other plant species (68%) than adults, especially in the first two weeks, possibly because of their inexperience. Late in the brood-rearing period, as the nitrogen concentration of graminoid plants declined, adults shifted to a diet composed mainly of berries (>40%, mostly Empetrum nigrum). At that time, goslings consumed fewer berries (24%) and maintained a higher proportion of nitrogen-rich plants in their diet (53% leaves, mostly graminoids) than adults, presumably to complete their growth. Plant species consumed by geese over the summer indicated a preference for high-quality plants (i.e. those with a high nitrogen concentration). Consequently, wet sedge meadow, the habitat that offered plant species of highest quality, was the habitat most heavily used throughout the summer, particularly around peak hatch. Goose grazing had no effect on seasonal production of aboveground biomass of graminoids, probably because of the relatively low density of the goose population.Écologie alimentaire de Branta canadensis interior pendant la période d’élevage des jeunes dans un milieu d’eau douce sub-arctique
Acoustic Properties of Two Urban Song Dialects in the Orange-Tufted Sunbird (Nectarinia Osea)
Authors: Leader Noam , Wright Jonathan , Yom-Yov Yoram 
Published: September 2019

AbstractBiologically important acoustic signals must be transmitted from a signaler to a receiver. Over distance, however, sounds may undergo modification through attenuation, degradation, and masking. Recent anthropogenic habitat modification occurring in many places—in urban habitats, in particular—has rapidly changed local topography and atmospheric conditions and generated new patterns of noise that are likely to interfere with communicative signals. As part of a study of microgeographic song dialects in an urban population of Orange-tufted Sunbirds (Nectarinia osea) in Israel, we examined the environmental influences on song transmission and reception in a rapidly developing human-altered environment. We examined the physical properties of the two dialect song types, which exhibit a large difference of 2–3 kHz in the maximum frequency of the trill, using sound transmission measurements to test how both song types propagate through a highly obstructed habitat of buildings and vegetation. Additionally, we examined how ambient noise—in particular, low-frequency noise arising mainly from automobile traffic—affects the transmission of both dialect songs. Finally, using song playback, we investigated the consequences of sound degradation on dialect recognition and discrimination by sunbirds. The dialect containing higher frequencies in the trill was found to undergo severe frequency-dependent attenuation, in which the maximum frequency of the trill notes drops by >2 kHz over a distance of 70–100 m (less than two territories away). Also, the possibility that the use of higher frequencies in that dialect group's song is intended to overcome masking by urban ambient noise, which is concentrated mainly in lower frequencies, was not supported by our findings. Males singing the high dialect responded differently to playbacks of an intact and an attenuated form of their dialect song. Taken together, our results suggest that the dialect containing higher frequencies in the trill may be unsuitable for effective long-range transmission through this particular sunbird habitat.Propiedades Acústicas de Dos Dialectos del Canto Urbano de Nectarinia osea
Calcium Availability Limits Reproductive Output of Tree Swallows (Tachycineta Bicolor) in a Nonacidified Landscape
Authors: Bidwell Mark T. , Dawson Russell D. 
Published: September 2019

AbstractBreeding birds require high levels of energy and certain nutrients, such as calcium. The extent to which calcium limits reproduction in wild birds is unclear. We performed a supplementation experiment to determine whether calcium limits the reproductive output of free-ranging insectivorous Tree Swallows (Tachycineta bicolor), a species whose usual diet contains little calcium. Providing supplemental calcium in the form of crushed oyster shell did not affect clutch initiation date, but it caused birds that had not started constructing a nest when we first detected them on the study area to begin laying sooner, which suggests that calcium reduced the length of the prelaying period. Supplemented females produced larger eggs, and that effect was most pronounced among females in good body condition. There was a trend for supplemented birds to produce larger clutches, and their clutches had significantly greater total mass than those of control birds. Supplemented birds, in particular those breeding late in the season, also hatched significantly more eggs. Our results suggest that calcium availability may limit some aspects of avian reproduction, even in nonacidified landscapes like our study area, where levels of calcium in the soil are high.La Disponibilidad de Calcio Limita el Rendimiento Reproductivo de Tachycineta bicolor en un Paisaje no Acidificado
A New Species of Aratinga Parakeet (Psittaciformes: Psittacidae) from Brazil, With Taxonomic Remarks on the Aratinga Solstitialis Complex
Authors: Silveira Luís Fábio , Thadeo de Lima Flávio César , Höfling Elizabeth 
Published: September 2019

Abstract
We describe a new species of Aratinga—A. pintoi (Sulfur-breasted Parakeet)—from open areas on the northern bank of the lower Amazon River in the state of Pará, Brazil. It was for a long time misidentified as a juvenile of A. solstitialis or a hybrid between that species and A. jandaya. It can be distinguished from other Aratinga species by the combination of the following characters: mantle and wing coverts green, suffused with pale yellow; underparts pale yellow, with pale orange restricted to belly and flanks; and feathers on the underparts with a dark rachis. On the basis of color characters and general morphology, we suggest that this new species should be a member of a group composed of A. solstitialis, A. jandaya, A. auricapillus, and, possibly, Nandayus nenday. A review of taxonomy and distribution of the group is also presented.
Uma nova espécie de Aratinga (Psittaciformes: Psittacidae) do Brasil, com comentários sobre a taxonomia do complexo de espécies Aratinga solstitialis
Body Mass of Long-Tailed Ducks (Clangula Hyemalis) During Incubation
Authors: Kellett Dana K. , Alisauskas Ray T. , Mehl Katherine R. , Drake Kiel L. , Traylor Joshua J. , Lawson Shona L. 
Published: September 2019

Abstract
We investigated body-mass dynamics during incubation of Long-tailed Ducks (Clangula hyemalis) nesting in Canada’s central Arctic, 1998–2003. Long-tailed Duck females (n = 37) lost 7% of pre-incubation body mass during incubation; on average, females weighed 618 ± 15 g (mean ± SE) at clutch completion and 575 ± 11 g at hatch. Given the differences in body size, Long-tailed Ducks relied less on endogenous reserves than sympatric King Eiders (Somateria spectabilis), but lost less mass than similar-sized waterfowl species nesting in temperate climates. Preliminary data suggest that Long-tailed Ducks maintain similar or higher nest-attendance rates than temperate-nesting waterfowl of similar size, and we suggest that access to locally abundant, high-quality foods enable Long-tailed Duck females to maintain high incubation constancy without sacrificing female body condition. Nevertheless, Long-tailed Ducks appear to differ widely from most Arctic-nesting waterfowl in nutritional strategy for nesting.
Masse corporelle chez l’Harelde kakawi (Clangula hyemalis) au cours de l’incubation
Multiple-Day Constancy as an Alternative to Pooling for Estimating Mark-Recapture Stopover Length in Nearctic-Neotropical Migrant Landbirds
Authors: Morris Sara R. , Liebner David A. , Larracuente Amanda M. , Escamilla Erica M. , Sheets H. David 
Published: September 2019

Abstract
Capture-mark-recapture models require estimation of parameters that may be either constant or time-dependent. Open-population models have been adapted for use in estimating stopover duration of migratory songbirds. However, with data collected over an extended period or with relatively few recaptures, small sample sizes may preclude use of fully time-dependent models. Pooling is commonly used to reduce the number of parameters estimated in time-dependent models. In pooling, all captures and recaptures during a specified interval are treated as a single capture event, which results in a loss of information about recaptures within the interval. Additionally, pooling of banding data of migratory songbirds appears to bias stopover-length estimates upwards. An alternative to pooling is use of multiple-day-constancy models. Advantages of this approach include maintenance of all recapture data, simultaneous Akaike’s Information Criterion-based comparison of models using different constancy intervals, and unbiased stopover estimates.
Constancia de Múltiples Días como una Alternativa a la Combinación de Datos de Captura-Recaptura para Estimar la Duración de las Paradas de Aves Migrantes Neárticas-Neotropicales Terrestres
Mark–Recapture and DNA Fingerprinting Data Reveal High Breeding-Site Fidelity, Low Natal Philopatry, and Low Levels of Genetic Population Differentiation in Flammulated Owls (Otus Flammeolus)
Authors: Arsenault David P. , Stacey Peter B. , Hoelzer Guy A. 
Published: September 2019

AbstractOver a seven-year period, we used mark-recapture in a population of Flammulated Owls (Otus flammeolus) in the Zuni Mountains, New Mexico, to estimate adult breeding-site fidelity, mate fidelity, natal philopatry, and dispersal distances. We also used DNA fingerprinting to examine the genetic population structure of Flammulated Owls among four mountain ranges in New Mexico and one range in Utah. Mark-recapture revealed that adults are site-faithful and tend to maintain pair bonds between years, whereas juveniles show little natal philopatry. DNA fingerprinting revealed very low differentiation among populations, even between the New Mexico and Utah ranges, with population subdivision (FST) estimates ranging from 0.00 to 0.04. Heterozygosity values were high within each mountain range and, together with the low FST values, suggest that this Neotropical migrant may have long-distance natal dispersal and frequent intermountain dispersal.Datos de Marcado-Recaptura y Huellas Dactilares de ADN Revelan Alta Fidelidad a los Sitios de Cría, Baja Filopatría Natal y Bajos Niveles de Diferenciación Genética Poblacional en Otus flammeolus
More Than Kin and Less Than Kind: The Evolution of Family Conflict
Authors: Mumme Ronald L. 
Published: September 2019

Abstract
The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists' Union.