The extinct Puerto Rican Parakeet (Psittacara maugei) has been known with certainty only from Mona Island and is usually regarded as a poorly defined subspecies of P. chloroptera of Hispaniola. Examination of skin specimens and comparison of skeletons with fossil and archeological material from Puerto Rico, show that Psitticara maugei is a fully distinct species from P. chloroptera, differing in plumage and particularly in bill morphology, such that a probable difference in diet is suggested. The main range of P. maugei was Puerto Rico, with the Mona Island population being only an isolated outlier. Extinction took place on Puerto Rico by the mid-1800s and on Mona Island shortly after 1892 possibly because of a combination of habitat destruction, persecution for crop depredations, and disease.

When two species or subspecies hybridize, the parental taxa may become more similar or follow new directions as alleles from one enter the novel genetic and ecological environment of the other. Here, we document hybridization between two Dinopium woodpeckers in Sri Lanka: two subspecies of Black-rumped Flameback woodpeckers (Dinopium benghalense jaffnense and D. b psarodes, recently considered as a full species Lesser Sri Lanka Flameback Dinopium psarodes). Hybridization has been suspected for 130 years. We describe eight different forms of hybrids, only two of which were known historically, and pairing patterns that indicate hybridization. The species and subspecies along with numerous hybrids have now become a hybrid swarm in northern Sri Lanka.

The incidence rate of hybridization appears to be much higher for parulid warblers compared to other bird taxa. Over 50% of the species in this family have been reported to hybridize. Here, we report genetic and morphometric analysis of a suspected hybrid of a previously unreported species cross in the genus Oreothlypis, captured in a montane spruce-fir forest in the Adirondack Mountains of New York. We compared sequences of the mitochondrial ND2 and the nuclear Z chromosomal aconitase intron 9 to published warbler sequences to determine parentage, and compared plumage and morphology to museum specimens. ND2 sequence closely matched Orange-crowned Warbler (O. celata), while aconitase matched Nashville Warbler (O. ruficapilla). Because our specimen was a male and was homozygous for ruficapilla alleles at the Z chromosome, we determined the hybridization event occurred at least two generations ago. This suggests hybridization between these species produces viable offspring. Plumage of the warbler was nearly indistinguishable from pure Nashville Warbler specimens. A Principle Components Analysis of morphometric data showed the hybrid to be morphologically intermediate between the two parent species. This hybridization event occurred well outside of Orange-crowned Warblers' breeding distribution, a finding consistent with Hubbs' principle which states that hybridization is more likely when conspecifics are rare or unavailable. Our finding demonstrates the importance of specimen collecting and genetic methods in documenting aspects of natural history that may be cryptic or infrequent in nature.

Genetic analyses have documented restricted gene flow between two subspecies of Orange-crowned Warbler (Oreothlypis celata), and it is thought that south-central Alaska may be a zone of secondary contact between O. c. celata and O. c. lutescens. We evaluated six morphological variables in museum specimens and netted individuals of O. c. celata from central and southwestern Alaska, of O. c. lutescens from central inner-coastal California, and of putative hybrid or introgressed Orange-crowned Warblers from the Kenai Peninsula of south-central Alaska. Additionally, we evaluated data for two variables only of netted O. c. lutescens from the panhandle of southeastern Alaska. Our analyses of wing chord length, mass, tail length, and color of backs and undersides indicated that samples obtained from the Kenai Peninsula had means that lie between, and for the most part were significantly different from, the means of samples of presumably pure O. c. celata from farther north and west in Alaska, and O. c. lutescens from farther south and east in Alaska and/or farther south in central inner-coastal California. However, we found no significant differences among the means of tarsal lengths for three taxa/localities. Additionally, we found that the back and underside colors of putative intergrades tended to be closer to O. c. lutescens than to O. c. celata. The distribution of data points around the means for Kenai Peninsula samples did not appear to be bimodal for wing chord length nor for color of backs or undersides. This suggested that Kenai Peninsula samples were mainly composed of intergrades between populations of pure O. c. celata and O. c. lutescens, and were not samples composed mainly of a mixture of the two pure subspecies. These results also suggested, for wing chords, masses, tail length, and color of backs and undersides, that a blending inheritance pertained in putative intergrades between O. c. celata and O. c. lutescens.

Studies of the effects of climate change on migratory bird behavior have established that many species are shifting the average day of year of their arrival at nesting sites earlier. If migrating birds are adapted to arrive at the optimum stage in the growth season to maximize the availability of resources, then migration phenology shifts may result in arrival at nesting sites at selectively disadvantageous points in seasonal development of the nesting ecosystem. First arrival dates (FAD) are changing for many species, but we know little about shifts in the corresponding accumulated growing degree units (AGDU) of arrival date in association with increasing global temperatures. By transcribing field notes for migrant arrival times during the years of 1910–1950 in the region around Fargo, ND, we obtained a detailed and robust description of historical phenological patterns. Comparison of the arrival times of 83 of the same species in the same location over the past 10 years indicate that the majority of bird species studied are arriving earlier than they did historically. The accumulated growing degree units at the time of arrival deviated from past values by as much as 4–5% higher or lower depending on the species. In general, short-distance migrants have advanced their arrival times and reduced the AGDU at the time of arrival relative to long-distance migrants. These results indicate that changing climate is influencing bird migration patterns and leading to arrival of migrants at different points in the progress of the growing season relative to the past. The impacts of this divergence on fitness and selection are expected to influence the nature of future bird communities.

In the last 20 years, a westward expansion of the White-winged Tern (Chlidonias leucopterus) has been reported in Europe. Even though this species has become a regular breeder in some places, we lack basic information on the choice of breeding sites. The aim of the present work is to compare the habitat preferences of two closely-related species: the expansive White-winged Tern and the Black Tern (Chlidonias niger), which has been breeding in this part of Poland for a long time. The data were gathered in east-central Poland from late May to early July 2013. All potential tern nesting areas were searched over 40,000 km², river valleys in particular. There were 41 colonies of White-winged Terns with a total number of 1,348 pairs and 55 colonies of Black Terns with 666 pairs. A Generalized Linear Model (GLZ) showed differences between both tern species in habitat parameters. However, only two predictors—area of open habitat (meadows, arable fields) and habitat type (ox-bow lakes vs. waterlogged sedge fields)—were significant. White-winged Terns located their colonies in waterlogged sedge fields three times more often than Black Terns did, while the latter nested three times more frequently on ox-bow lakes. There was also a statistically significant greater proportion of open habitats around the colonies of White-winged Terns than around those of Black Terns. The colonies of the two species were roughly the same size in all habitats. This study showed that habitat type was the basic factor governing the choice of nesting site by these two closely-related tern species.

The Gunnison Sage-Grouse (Centrocercus minimus) is a species of conservation concern and is a candidate for listing under the U.S. Endangered Species Act because of substantial declines in populations from historic levels. It is thought that loss, fragmentation, and deterioration of sagebrush (Artemisia spp.) habitat have contributed to the decline and isolation of this species into seven geographically distinct subpopulations. Nest survival is known to be a primary driver of demography of Greater Sage-Grouse (C. urophasianus), but no unbiased estimates of daily nest survival rates (hereafter nest survival) exist for Gunnison Sage-Grouse or published studies identifying factors that influence nest survival. We estimated nest survival of Gunnison Sage-Grouse for the western portion of Colorado's Gunnison Basin subpopulation, and assessed the effects and relative importance of local- and landscape-scale habitat characteristics on nest survival. Our top performing model was one that allowed variation in nest survival among areas, suggesting a larger landscape-area effect. Overall nest success during a 38-day nesting period (egg-laying plus incubation) was 50% (daily survival rate; SE  =  0.982 [0.003]), which is higher than previous estimates for Gunnison Sage-Grouse and generally higher than published for the closely related Greater Sage-Grouse. We did not find strong evidence that local-scale habitat variables were better predictors of nest survival than landscape-scale predictors, nor did we find strong evidence that any of the habitat variables we measured were good predictors of nest survival. Nest success of Gunnison Sage-Grouse in the western portion of the Gunnison Basin was higher than previously believed.

The Sierra Nevada de Santa Marta in northern Colombia has been identified as a critical spring stopover site for at least one Neotropical migratory bird species prior to crossing the Caribbean sea on migration. The strategic location of the Sierra suggests that other South American wintering migrants may stopover there, but no information is available on the migrant community during spring or how they distribute themselves between habitats and across the broad elevational gradient. Here, we present species richness and densities of migratory landbirds obtained through standardized census and captures along an elevation gradient (100–2,100 m) covering two habitats, forest and shade coffee, during two consecutive spring migrations. The migrant community (~39 species) showed a peak in species richness and abundance at mid elevations (700–1,700 m), mirroring the pattern often observed in communities of resident Neotropical birds. However, individually the abundance of the commonest species peaked at different elevations and showed high annual variability. We also found within-species differences in density between shade-coffee and forest at the same elevation, possibly reflecting differences in habitat quality for some species. Factors such as food availability and predation risk are expected to be critical in shaping the distribution of migrants during stopover, and further research is required to identify the drivers of the observed elevational patterns. This study contributes to our knowledge of the life histories of migrants during stopover and highlights the habitats and elevations where conservation measures would protect the highest number of species and individuals at a South American stopover site.

We document male and female roles in nestling care of Spotted Barbtails (Premnoplex brunnescens) including feeding rates and temporal patterns of provisioning by each sex. Using 128.5 hrs of video from color marked and molecularly sexed individuals at two nests, we confirm that both sexes of Spotted Barbtail provision nestlings. Spotted Barbtail females in our study invested more heavily in nestling care than males, making 73% of feeding visits. Females also visited the nests nearly twice as often as males, averaging 1.24 visits/nestling/hr compared to 0.69 visits/nestling/hr for males. While Spotted Barbtails exhibit many of the features assumed to favor social and genetic monogamy, intriguing aspects of nest building and incubation leave open the possibility that this species is unusual among the Furnariidae and utilizes extra-pair matings as a part of the reproductive strategy.

The Myiotheretes bush-tyrants are a small clade of Neotropical flycatchers (family: Tyrannidae) localized to narrow elevational strips in the Andes Mountains. Here, we describe the first reported nest of Rufous-bellied Bush-Tyrants (Myiotheretes fuscorufus). It was a large cup nest lined with Usnea lichen and elevated on a sheltered rock ledge behind a flowering Puya bromeliad at 2,985 m asl in the buffer zone of Manu National Park, Peru. We provide a near-complete history of the nest from eggs through fledging, and compare data with previous nesting reports for other Myiotheretes species.

Longevity records inform demographic studies and our understanding of avian senescence evolution, yet studies on free-ranging species are rare, especially in the tropics. Here we provide minimum longevity records for the Marsh Antwren Formicivora acutirostris (Thamnophilidae), a small (9.8 g) territorial bird inhabiting tidal marshes in southern Brazil. We recorded a 16.2-year-old male and a 14.2-year-old female, both breeding before they were last seen, as well as 31 individuals between 6–10.2 years of age. There was no difference in the sex-ratio between these individuals. The oldest male was nearly 2 years older than the oldest thamnophilid recorded to date, and twice as old as the oldest recorded breeding individual. We also observed behaviors which we interpret as signs of aging, such as the isolation of the old female and her apparent indifference to her mate, and frequent territory disputes involving the old male and floater males.

Predation is dangerous, not only for the prey but sometimes also for the predator. Because these dangers to predators are not well understood, we document evidence of predation or scavenging by a Golden Eagle (Aquila chrysaetos) on a North American porcupine (Erethizon dorsatum) in Pennsylvania, USA, with potentially lethal consequences to the eagle. We also review published literature on incidence of porcupine quills causing injury or death to birds. At least nine species have been documented as having contact with porcupine quills. A minimum of 39% of these interactions resulted in death to the bird, demonstrating the risk birds face when interacting with porcupines. Predation of porcupines should be selected against and irregular, yet it apparently persists and is likely more common than currently recognized.

Nocturnal roosting at locations disjunct from daytime foraging areas (hereafter disjunct nocturnal roosting) is a common avian behavior on both the breeding and wintering grounds but to our knowledge has not been documented in arboreal passerines during migratory stopover. We report observations of a spring migrant Yellow-rumped Warbler (Setophaga coronata) commuting to a nocturnal roost site 2.6–3.2 km north from its 5.1–9.0 ha daytime home ranges on two consecutive stopover days. We discuss the potential significance of this behavior in terms of roost habitat type, predator avoidance, and thermoregulation. We encourage those conducting telemetry studies on stopover migrants to examine existing data and, when possible, to use tracking methods that advance understanding of the behavioral ecology of nocturnal roosting and the prevalence of and causes for disjunct roosting.

We report a unique case of two female Barn Owls laying eggs and incubating together in a single nest cup in a communal nest. A trio of two females and one male bred in an abandoned water tower in 2013 in Israel. Both females incubated/brooded together in the communal nest, and all three individuals brought food to the communal family. The two females laid 20 eggs, of which 19 hatched and 16 fledged.

Because of recent increases in populations of Black Vultures (Coragyps atratus) and Turkey Vultures (Cathartes aura), vulture-human conflicts have become more common. We can begin to mitigate these conflicts by first identifying what attracts these birds. We investigated the use of thermal power plants (TPPs) by vultures in Manaus, Central Amazon, Brazil, from February–September 2012, and monitored six TPPs throughout urban areas. We visited each TPP six times at three intervals. At all TPPs, we observed vultures use artificial thermals as a way to gain elevation during flight. The largest number of vultures was observed in TPPs near feeding sites and roosting areas. We recorded the largest concentration of vultures in the late afternoon. We observed an interaction effect between site and time, where TTPs near roost sites had more vultures early morning and late afternoon, while TPPs near feeding sites had more vultures at mid-day. Our results show that vultures intensively use TPPs to aid their flight, and this behavior is used mainly at those times under the lowest natural thermals and when the vultures are moving from feeding sites to roosts in the late afternoon.

As far as we know, becards are socially monogamous. This group includes the five members of the monophyletic Platypsaris clade, nested within Pachyramphus. These five species have white scapular feathers which are usually hidden and whose function has been largely ignored by ornithologists. Because of becards' conspicuous, bulky nests, comparatively more is known about their breeding biology than about that of many other Neotropical groups, though much remains to be learned on this subject even in becards. Breeding behavior of becards has been considered relatively ordinary, but the displays we report reflect more complexity than previously supposed. We provide evidence that at least four of the five members of the Platypsaris clade (Rose-throated, Pink-throated, One-colored, and Crested becards) engage in courtship displays, some of which are dramatic. The normally hidden white scapulars are employed as erectile “badges” in these displays.

Social interaction between juvenile and adult brood parasitic cuckoos is rarely documented, but may influence social development, sexual preferences, or song learning. The Striped Cuckoo (Tapera naevia) is a New World brood-parasitic cuckoo that uses counter-singing and duets in reproduction and territory defense. Here, we report the first observations of adult-juvenile social interactions in the Striped Cuckoo. In contrast to their normally solitary lives, juveniles and adults moved and foraged together and engaged in counter-singing and duets. Striped Cuckoo adults often initiated the social interactions and engaged in vigilance behaviors when with the juveniles. We suggest further study to determine if adults are interacting with related juveniles.

Interspecific competition among secondary cavity nesters can involve physical conflicts between individuals, which may lead to serious injuries or death. Here we report a case of aggression by a pair of Chilean Swallows (Tachycineta meyeni) towards a nestling of the Thorn-tailed Rayadito (Aphrastura spinicauda) in the sub-Antarctic forests of Chile. This aggression caused the displacement of the breeding rayaditos from an occupied nest box and it appears, nestling mortality. Since levels of aggression among cavity nesters depend on the synchrony of their breeding phenologies, further research is needed to study the prevalence of nest usurpation by Chilean Swallows and its relation to the degree of breeding synchrony with other cavity nesters inhabiting the sub-Antarctic forests.

Turkey Vultures are one of the most widely distributed carrion feeders throughout the Americas. We analyzed their regurgitated pellets from two localities in the Atacama Desert of Chile. Natural foods included dogs, sea lions, and feathers present in 17% of the pellets. We also found that 78% of pellets from coastal sites and 83% of pellets from inland sites contained plastic material. Plastic was likely ingested because vultures scavenge in plastic bags disposed as garbage along roads and beaches. Plastic ingestion has been documented in marine birds but only occasionally in raptors. Seabirds are vulnerable to the effects of ingested plastics because of their inability to regurgitate this material. Although vultures can regurgitate plastic, we do not know the physiological effects related to ingestion of the material. The availability of food from garbage bags could partly explain the widespread distribution of these vultures in the desert, but the inclusion of these items in their diet likely provides little to no energy. Turkey Vultures patrol roads in search of animals hit by vehicles, which facilitates finding carrion and garbage. Garbage in plastic bags has increased as more roads have been built in these areas; in the future, it will be important to study the effects of ingested plastics on these birds.

Galapagos Mockingbirds (Mimus parvulus) are opportunistic feeders that have been observed engaging in a variety of unusual predatory behaviors. Here, we report on a specific behavior that we observed: a Galapagos Mockingbird preying on an invasive mammal by repeatedly hitting it on the ground. We discuss the reasons that the mockingbird might have engaged in this behavior and the potential implications this could have for native biodiversity and conservation on the Galapagos Islands.

We sequenced a diagnostic fragment of the mitochondrial Cytochrome b (Cyt b) gene in 144 flycatchers, identified only as “Traill's flycatchers,” which were collected during spring and fall migration of 1973 and 1974 in the Tuxtla Mountains, Veracruz, Mexico. We found 135 E. alnorum, 3 E. traillii, 3 E. virescens, and 3 that did not match any known Empidonax sequence. Thus, E. traillii is an infrequent migrant in spring and fall in northern Veracruz, and instead likely passes along the southern part of the Isthmus of Tehuantepec as other studies have found. We also sequenced Cyt b mitochondrial DNA from toe pads of study skins of these species. Of 11 identified on the label as E. alnorum, one was E. traillii whereas the rest were E. alnorum. Of 16 specimens identified on the label as E. traillii, only one was actually this species; fourteen were E. alnorum and one was an E. virescens. Thus, we suggest that the species identification of specimens labeled as E. alnorum and E. traillii taken during migration should be considered speculative.

We provide the first detailed descriptions of the nest cavity and eggs of the White-tailed Quetzal (Pharomachrus fulgidus) from the montane forest of the SW slope of the Sierra Nevada de Santa Marta, northern Colombia. We found two active cavities (both >2.5 m high) in isolated tree snags of non-native Mexican weeping pine (Pinus patula). One cavity contained two unmarked, pale turquoise eggs at the bare base. The nest cavity and eggs of the P. fulgidus resemble those of other high elevation species of quetzals. Breeding occurs in the first half of the Julian calendar during the end of the dry season. Additional information about the breeding biology of this group of birds is warranted.

Long-tailed Jaegers (Stercorarius longicaudus) normally lay one or two eggs (rarely three), with a maximum of two eggs set by the existence of only two brood patches. Here, however, we present the first documentation of a clutch of four eggs in a Long-tailed Jaeger nest found at Zackenberg in northeastern Greenland.

We present the first documented record of the Ornate Hawk-Eagle (Spizaetus ornatus) in the Caatinga Biome. We tape-recorded a single individual from the Serra das Confusões National Park in southern Piauí in March 2013. This record represents a range-extension of ~390 km from the nearest site in western Bahia, and highlights the likelihood of further major ornithological discoveries from this region that still remains poorly inventoried.