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Tuesday, 6 October 2015

Wilson Journal of Ornithology September 2015 : Volume , 127 Issue 3

The Wilson Journal of Ornithology
Published by: The Wilson Ornithological Society



Table of Contents
September 2015 : Volume , 127 Issue 3

LINK


MAJOR ARTICLES

Prehistoric birds from the Lake Titicaca region, Bolivia: long-term continuity and change in an Andean bird community
David W. Steadman and Christine A. Hastorf

Abstract
From excavations at the Formative period (3,500 to 900 years old) Chiripa archaeological site on the southern shore of Lake Titicaca on the Bolivian altiplano (elev. 3,820 m), we identified 664 bones that represent 41 extant species of birds. Approximately 80% of the bones are from aquatic species such as coots, grebes, ducks, cormorants, and flamingos. Ten species from the bone sample (a grebe Podiceps occipitalis, cormorant Phalacrocorax brasilianus, goose Chloephaga melanoptera, duck Lophonetta specularoides, falcon Falco peregrinus, coots Fulica gigantea and F. leucoptera, dove Metriopelia aymara, owl Asio flammeus, and trogon Trogon personatus) were not recorded during rigorous bird surveys at Chiripa and elsewhere on the Taraco Peninsula in June-July 1996. One of these species (Trogon personatus) inhabits humid montane forest below 3,400 m elevation, and thus probably was transported by people to Chiripa from distances >80 km away. Each of the other nine species except Fulica leucoptera are known to occur regularly within the Titicaca Basin. The prehistoric data support the hypothesis that the regional composition of most continental Neotropical bird communities, in spite of many local range fluctuations, has been fairly stable over the past several millennia, a period of minor climate change compared to that of glacial-interglacial transitions. A challenge to researchers is to tease out the possible causes of local distributional changes in Neotropical birds, including an evaluation of how prehistoric people may have affected the presence and relative abundance of certain species. Received 3 September 2014. Accepted 27 February 2015.


Acoustic differences enable sex discrimination in Ma'oma'o (Gymnomyza samoensis), a species with high sexual morphological overlap
Rebecca L. Stirnemann, Murray A. Potter, David Butler and Edward O. Minot

Abstract
A field technique to identify sex is critical for facilitating conservation of species where declines are potentially unequal between the sexes. Although morphometrics are often used to sex individuals in the field, for many tropical and seabird species there is extensive morphometric overlap between the sexes. Accurate sexing of individual birds for research and conservation is thus reliant on genetic analysis, which is not instantly available. In this study we use an endangered tropical bird, the Ma’oma’o (Mao) (Gymnomyza samoensis), as a case study to investigate reliable methods for accurately determining sex in the field for a species with extensive sexual morphometric overlap. We provide the first comprehensive description of its vocalizations and morphology and examine whether individuals of this apparently sexually monomorphic species can be accurately sexed using three features: morphometrics, eye color, and vocalizations. Acoustic analysis, which measured the central frequency of Ma’oma’o alarm calls, allowed sex of all sampled individuals to be correctly identified and was the most accurate mechanism for sexing Ma’oma’o in the field. Our results also indicated that despite high morphometric overlap binomial generalised linear models enabled 54% of the Ma’oma’o to be sexed with 95% confidence in the hand. Individuals that had a high probability of being incorrectly sexed could also be identified. Eye color did not allow strict delineation of the sexes, although the only birds with blue eyes were adult males. We propose that using vocalizations to differentiate sex should be investigated further in other bird species. Not only can it provide an accurate method which does not require capture, but it may also be useful when combined with automatic sound recorders for monitoring sex ratios in bird populations where the greater decline of one sex is suspected.


Winter composition of Nelson’s Sparrow (Ammodramus nelsoni) and Saltmarsh Sparrow (Ammodramus caudacutus) mixed flocks in coastal Virginia 
Bryan D. Watts and Fletcher M. Smith

Abstract
We captured 1,055 Nelson’s (Ammodramus nelsoni) and Saltmarsh (Ammodramus caudacutus) sparrows during the winter season (2006–2014) within the outer Coastal Plain of Virginia to determine the composition of subspecies. Birds were captured using mist nets in 24 tidal salt marshes and identified to subspecies using a plumage-based, syntopic key. Contrary to previous assessments, both species of sharp-tailed sparrows were common. All five subspecies were present and appeared to form mixed flocks within patches. The north-Atlantic Saltmarsh Sparrow (A. c. caudacutus) was the most common form, accounting for 45% of all birds identified to subspecies. The three Nelson’s Sparrow forms including the “Acadian” Nelson’s Sparrow (A. n. subvirgatus), “James Bay” Nelson’s Sparrow (A. n. alter) and the “Nelson’s” Sparrow (A. n. nelsoni) were equally common and collectively accounted for 47% of the subspecies identified. The highly restricted, mid-Atlantic Saltmarsh Sparrow (A. c. diversus) was the least common, accounting for only 8% of individuals. Subspecific composition did not vary with geography in the region. Age ratios for both Nelson’s and Saltmarsh sparrows were significantly skewed to hatching-year (HY) rather than after-hatching-year (AHY) birds. However, age ratios varied dramatically across years for both species. The annual portion of birds accounted for by the HY class ranged from 31.3 to 77.5% and 36.7 to 70.3% for Nelson’s and Saltmarsh sparrows, respectively. Information from Virginia represents a significant extension of current perceptions about the winter distribution of these forms.


Overlapping home ranges and microhabitat partitioning among Canyon Wrens (Catherpes mexicanus) and Rock Wrens (Salpinctes obsoletus) 
Nathanial Warning and Lauryn Benedict

Abstract
Patterns of animal space use may vary according to species identity, presence of conspecifics, presence of heterospecifics, and resource availability. We evaluated joint space use by Canyon Wrens (Catherpes mexicanus) and Rock Wrens (Salpinctes obsoletus) by comparing home range sizes, home range overlap, and foraging behavior. Canyon and Rock wrens are ecologically similar species which frequently co-occur along rocky cliffs where members of both species feed on terrestrial invertebrates. Interactions between Canyon and Rock wrens provide information about avian space use and foraging strategies in understudied cliff habitats. We estimated home range for each species using ArcGIS, and quantified foraging microhabitat use. Canyon Wren home ranges were widely spaced, did not overlap conspecifics, and were significantly larger than those of Rock Wrens. Rock Wrens occurred at higher densities and home ranges overlapped conspecifics in 33% of cases by an average of 19%. Canyon and Rock wren home ranges overlapped in 68% of cases by an average of 28%, but overlapping pairs rarely shared core use areas. The two species differed significantly in foraging microhabitat use. Results suggest that heterospecific territory defense between Canyon and Rock wrens is low, and that these species have adopted different methods for using shared resources in escarpment and cliff habitats.


Breeding biology of the Sooty Swift (Cypseloides fumigatus) in São Paulo, Brazil
Renata Neves Biancalana

Abstract
The Sooty Swift (Cypseloides fumigatus) is one of five species in this genus that occur in Brazil. There is little information regarding its breeding biology and in the Brazilian state of São Paulo, the species is described as data deficient. This study describes the breeding biology of the Sooty Swift at Intervales State Park in São Paulo, southern Brazil from 2012 to 2014. Nests were monitored weekly at two waterfalls during the reproductive season. Nest construction started in mid-October. Egg laying started in late October with a clutch size of one egg. The incubation period was 27–29 days, and the average nestling phase was 56 days. Fourteen active nests were found, and six nestlings were monitored from hatching to fledging for plumage development, behavior, and provisioning. Adult activity was observed during nocturnal visits. A second egg was laid on four occasions: two after the loss of the first egg and two after a successful fledgling left the nest, but the latter two were not successful. The Sooty Swift shares similar nest site characteristics, phenology, and nestling behavior with other Cypseloides spp. Nocturnal visits to breeding sites reveal a very active environment and such visits should be encouraged to better understand the behavior of the Sooty Swift.


Prey items of the Black Swift (Cypseloides niger) in Colorado and a review of historical data
Kim M. Potter, Carolyn Gunn and Jason P. Beason

Abstract
The Black Swift (Cypseloides niger) was first discovered in Colorado in 1880, yet information on prey items taken by this species in Colorado is very rare. We collected and identified prey items of Black Swifts from three breeding locations in Colorado during August over a seven-year period (2006–2012) and identified 5,371 insects representing 10 orders and 54 families. We compare our data with historical Black Swift prey item information from other locations in North America. These data indicate that Black Swifts forage on a wider array of insect taxa and sizes than previously reported in other parts of its range.


Aggressive behavior by Western Bluebirds (Sialia mexicana) varies with anthropogenic disturbance to breeding habitat
Manisha Bhardwaj, Catherine A. Dale and Laurene M. Ratcliffe

Abstract
Human population growth has resulted in more frequent interactions between humans and wildlife, making it increasingly important to understand how anthropogenic disturbance affects animal populations. A number of recent studies on birds have shown that individuals experiencing high levels of disturbance are frequently more aggressive than conspecifics living in less disturbed areas. Our study asked whether heterospecific aggression varied in Western Bluebirds (Sialia mexicana) breeding in artificial nest boxes over a gradient of human disturbance in the Okanagan Valley of British Columbia, Canada. Unlike most previous studies, which have investigated effects of high disturbance (urbanization), our study focused on sites with lower rates of human disturbance, including ranch lands, vineyards, and recreational trails. Using decoys and playback, we measured the response of bluebird pairs to a simulated territory intrusion by one of two heterospecifics: a competing cavity nester, the House Wren (Troglodytes aedon), and a non-competing species, the American Goldfinch (Spinus tristus). We asked whether this response varied with the level of human disturbance experienced by the pair, and also whether aggression was correlated with female flight initiation distance (FID; a measure of boldness), local density of boxes in a territory, and presence of neighboring cavity-nesters. Overall, aggression was significantly higher towards the competitor stimulus (wren) than the non-competitor (goldfinch). Aggression towards the wren model did not change with disturbance level; however, aggression towards the goldfinch model increased significantly in more disturbed areas. Female FID did not vary across disturbance categories, but was correlated with aggression towards the wren, where individuals that responded more aggressively had marginally larger FIDs (i.e., behaved less boldly). Female FID was not correlated with aggression towards the goldfinch. Birds nesting in territories with more boxes tended to be more aggressive towards the wren, and birds nesting in territories with one or more box-nesting neighbors were significantly more aggressive towards the wren than birds without neighbors. Neither of these factors was correlated with aggression towards the goldfinch. Thus, the predicted association between disturbance and aggression was detected only in response to the non-competitor species (goldfinch), whereas aggression towards the competitor species (wren) varied with territory quality and number of competitors. Our study shows that variation in low levels of anthropogenic disturbance may be associated with behavioral effects in bird populations, and serves as a reminder that different factors may influence the expression of aggression in different contexts.


Breeding biology and nest survival in Tropical Screech-Owls (Megascops choliba) in the Brazilian Cerrado
Raphael Igor Dias and Marcos Lima Robalinho

Abstract
Different ecological parameters are associated with the selection of nests and breeding sites in birds. Understanding nest-site selection and the subsequent consequences for reproductive success are critical to a full understanding of how natural selection shapes birds’ nesting behavior. Between 2007 and 2008, we evaluated nest-site characteristics and nesting success of Tropical Screech-Owls (Megascops choliba) in an area of Cerrado interspersed with cultivated areas in central Brazil. We compared the characteristics of cavities used for nesting by owls and unused nesting cavities and modeled nest survival in MARK. Models were assessed using Akaike’s Information Criterion for small sample sizes (AICc) and model averaging was used to infer model parameters. Tropical Screech-Owls nested in tree and termite-mound cavities. Nest success was 44.4%, with predation being the main cause of nest failure. We found that Tropical Screech-Owls nested in cavities with different orientations, and closer to the ground than unused cavities. Although the top-ranked models included nest height and nest concealment, multimodel inference showed that these variables had no clear effect on nest survival. Despite the lack of effect of these variables on nest survival, nest-site characteristics commonly associated with a cavity’s microclimate (i.e., orientation of cavity entrance) may still have a stronger influence on nest-site selection.


Breeding biology of the Lesser Grass-Finch (Emberizoides ypiranganus) in southern Brazilian upland grasslands
Eduardo Chiarani and Carla S. Fontana

Abstract
We studied the breeding biology of the Lesser Grass-Finch (Emberizoides ypiranganus), a bird with a little-known life history, in upland grassland of the Atlantic Forest (Mata Atlântica) Biome in southern Brazil. We collected data for 93 nests over two breeding seasons (2012–2014). We assessed how some covariates influence the daily survival rates and affect nest survival, building models in Program MARK. Breeding begins in early October, peaks in late November, and continues until early March, lasting approximately 150 days. The mean size of breeding territories was 1.1 ha, and territories located in burned areas were smaller than those in unburned areas. Only the females build the small open-cup nests, in clumps of grass (mainly composed of Andropogon lateralis, Schizachyrium tenerum and Sorghastrum setosum) at 36.2 cm above the ground. The clutch size is three (67%) or two eggs (n  =  52), and laying occurs on consecutive days. Incubation is performed by the female and lasts 13.7 days. The mean period of on-bouts was 73.5 min and the mean period of off-bouts was 39 mins. The hatching is synchronized and the hatching rate was 94%. In most nests, both the female and male fed the nestlings (biparental care). The frequency of visits/hr to feed the young did not differ with nestling age, but the length of visits was longer when the nestlings were younger. Nestlings fledged after 9–12 days. The apparent success was 42%, with 39% and 35% breeding success when calculated with the Mayfield estimate and the MARK software program, respectively. Predation was the main cause of failure, affecting 76% of the unsuccessful nests. The best models included time-specific factors (nest age and year) and nest-site features (nest height and habitat) influencing nest survival. Daily survival rates decreased through the nest cycle, and were much lower in the nestling stage. The re-nesting interval after nest failure was 2.7 days, and the mean distance between consecutive nesting attempts was 104.2 m. Up to four attempts (n  =  5) by the same female were observed in the same breeding season. Although little published information is available for this species, the basic reproductive features are very similar to those found in a population in Argentina. In Brazil, the breeding season is slightly shorter, and clutches of two eggs are more common.


Overwintering Sandhill Cranes (Grus canadensis) in Nebraska, USA
Mary J. Harner, Greg D. Wright and Keith Geluso

Abstract
Over half a million Sandhill Cranes (Grus canadensis) migrate through Nebraska, USA, each autumn and spring, but only a few cranes have been reported in Nebraska during winter. In early winter of 2011, however, an estimated 4,000–5,000 Sandhill Cranes were observed in south-central Nebraska along the Platte River. At that time, we initiated a study to search for and document Sandhill Cranes within the Platte River Valley across three winters and relate winter crane observations for the recent period to historical late autumn, winter, and early spring sightings in Nebraska documented by citizen observers for a century. We observed thousands of Sandhill Cranes along the Platte River in winters 2011–2012 and 2012–2013, but none in 2013–2014. Winters 2011–2012 and 2012–2013 were notable for a combination of mild conditions in Nebraska coupled with severe to exceptional drought in the southern United States and northern Mexico at traditional wintering areas for cranes. Analysis of historical observations indicates such large numbers of Sandhill Cranes have not been documented previously during winter in Nebraska, with the exception of 5,000 cranes near Grand Island, Nebraska, on 15 December 1990 that were not reported again following an arctic blast 2–3 days after the sighting. Reported dates of first spring arrivals have shifted over time, with Sandhill Cranes returning progressively earlier in spring in more recent years. If Sandhill Cranes continue to overwinter and/or arrive earlier in spring, there may be consequences for inter-species interactions with migratory waterfowl, such as competition for waste grains or transmission of disease, within the Platte River Valley, as well as for the timing of habitat-management activities. Ongoing monitoring of cranes during winter and early spring will track these patterns to better inform managers of habitat and food resources to help meet the species’ needs.


Moderate livestock grazing of salt, and brackish marshes benefits breeding birds along the mainland coast of the Wadden Sea
Freek S. Mandema, Joost Tinbergen M., Bruno J. Ens, Kees Koffijberg, Kees S. Dijkema and Jan P. Bakker

Abstract
Our study investigated how bird species richness and abundance was related to livestock grazing on salt, and brackish marshes, with an emphasis on songbirds, and shorebirds. Survey areas with a high percentage cover of tall vegetation were assumed to have experienced lower livestock grazing intensities than survey areas with a low percentage cover of tall vegetation. This relationship was verified for the tall grass Elytrigia atherica. The species richness, and abundance of birds was related to the percentage cover of tall vegetation on the survey areas. We found that total bird species richness was positively related to the percentage cover of tall vegetation. We also found that all of the investigated species, except Pied Avocet (Recurvirostra avosetta), showed a positive relation to the percentage cover of tall vegetation up to a specific percentage of cover. The abundance of investigated songbird species increased up to an intermediate percentage cover of tall vegetation, and decreased at higher percentage cover of tall vegetation, suggesting that moderate grazing of marshes may maximize the abundance of the investigated songbirds. Abundances of Common Redshank (Tringa totanus) and Eurasian Oystercatcher (Haematopus ostralegus) were positively related to the percentage cover of tall vegetation on salt marshes, but negatively related to the percentage cover of tall vegetation on brackish marshes. With intermediate livestock grazing species number, and abundance of most breeding birds can be maintained in coastal marshes. However, specific goals for management should be set before applying a grazing regime to a marsh.


Habitat use and nesting success of the Great Reed Warbler (Acrocephalus arundinaceus) in different reed habitats in Serbia
Measuring Thomas Oliver, Antun Žuljević, Katalin Varga and Szabolcs Lengyel

Abstract
We surveyed five reed habitats (mining pond, sand pit, large canal, small canal, and lowland river) in north-western Vojvodina (Serbia) between 2009–2011 to study habitat use and to estimate nesting success in an understudied region of the breeding range of the Great Reed Warbler (Acrocephalus arundinaceus). Data from 174 nests showed that habitat use differed considerably between habitat types but was not related to the area of the study site or the reed bed. Higher than expected numbers of nests along the small canal and the river suggested that Great Reed Warblers preferred these to other habitats for nesting. Habitat use was closely linked to the availability of reed edges and the quality of the reed stand. Overall Mayfield nesting success was 43%, slightly lower than in northern and western Europe. Nesting success was low along the small and large canal, where brood parasitism by Common Cuckoos (Cuculus canorus) and nest predation were high because of the nearby presence of tree lines that provided perching sites for cuckoos and predators. Nesting success was intermediate at the mining pond because of high predation pressure and adverse weather, and nesting success was highest in the sand pit (despite high cuckoo parasitism) and the river (despite relatively high predation). Our results suggest that canals can function as ecological traps, which attract edge-preferring Great Reed Warblers but are highly accessible to predators and brood parasites. In contrast, sand pits can be perceptual traps because they provide good resources for nesting but were less attractive to Great Reed Warblers than other habitats. Habitat use in relation to habitat availability thus depends primarily on the availability of reed edges and the quality of the reed stand, whereas nesting success also depends on the characteristics of the surroundings and weather conditions.


Oviposition behavior in Glaucous-winged Gulls (Larus glaucescens) 
Gordon J. Atkins, Amanda G. Sandler, Mindy McLarty, Shandelle M. Henson and James L. Hayward

Abstract
Little is known about oviposition in colonial seabirds. Egg-laying behaviors of Glaucous-winged Gulls (Larus glaucescens) were recorded using custom-modified digital pocket spy cameras. Oviposition involved standing or crouching over the nest, a series of contractions while assuming a characteristic posture, a short labor vocalization at the peak of contraction by some gulls, and a drying time while standing over the nest after oviposition. Active camouflage by some females was noted while sitting on the nest prior to and after oviposition and after an egg robbery occured. Eggs were laid throughout the day and night. Not surprisingly, given that our study occurred during the first part of the egg-laying season, Poisson regression analysis showed that egg laying increased with the day of the year. It decreased with solar elevation. Egg losses by cannibalism and predation increased with rising tides and with the day of year when more eggs were present. The implications for egg censuses are discussed.

SHORT COMMUNICATIONS

Intra-Summer Movement and Probable Dual Breeding of the Eastern Marsh Wren (Cistothorus p. palustris); a Cistothorus Ancestral Trait?
Mark B. Robbins

Abstract
Midwest breeding populations of the eastern North American Marsh Wren (Cistothorus p. palustris) perform intra-summer movements presumably to breed at two different locations during the same summer. It appears that birds that initially breed during May-June move south to breed again during mid-July through August. Because this unique behavior is shared with its closest living relative, the North American Sedge Wren (C. platensis stellaris), it may be an ancestral trait of Cistothorus.


Genetic Verification of Dizygotic Twin Embryos in the White-throated Sparrow (Zonotrichia albicollis)
Adam M. Betuel, Elaina M. Tuttle and Rusty A. Gonser

Abstract
The incidence of twinning in avian species is a phenomenon that has been rarely encountered. A number of domestic species have been shown to produce twins but in very low numbers. In wild populations, only 14 species have been documented producing twin embryos or nestlings. Despite this, it has been postulated that birds are just as likely as any other vertebrate to produce twin offspring. Here we describe the discovery of dizygotic twins in a long-term study of breeding ecology in the White-throated Sparrow (Zonotrichia albicollis). The twin containing egg was 12% heavier than the mean and had a mass greater than 94% of eggs collected. The twin containing egg was wider and longer than the majority of other eggs collected during 2010 but still within the expected range for White-throated Sparrows. Genetic analysis demonstrated that the twin embryos were full siblings but of different morph and sex. This is the first documented case of twinning in our study site out of over 2000 samples over 25 years of study, and likely the first confirmed case of twinning in this species.


Forensic Techniques Identify the First Record of Snowy Owl (Bubo scandiacus) Feeding on a Razorbill (Alca torda)
Carla J. Dove and Charles P. J. Coddington

Abstract
Stomach contents were analyzed using microscopic feather characters and osteological comparisons to document the first record of a Razorbill (Alca torda) being eaten by a Snowy Owl (Bubo scandiacus). Careful comparisons of fragmented morphological evidence in combination with geographic location and other circumstantial data can enhance dietary analyses, especially when it is difficult to obtain DNA sequences from the degraded and digested stomach contents.


Nutrients Drive Termite Nest Geophagy in Yellow-chevroned Parakeets (Brotogeris chiriri)
Raul Costa Pereira, Francisco Severo-Neto, Igor Inforzato, Rudi Ricardo Laps and Marcus Aurelius Pizo

Abstract
We observed Yellow-chevroned Parakeets (Brotogeris chiriri) consuming soil from arboreal termite nests while excavating a nest cavity. As most observations of parrot geophagy come from clay licks, this observation prompted questions about the benefits of consuming termite nest soil rather than ground soil. We compared nutrient contents and chemical properties (organic matter, pH, cation exchange capacity, macro and micronutrients) from these two types of soil. Termite nest soil had higher concentrations of macronutrients and cation exchange capacity than ground soil, which may be related to mineral supplementation and binding of toxins present in fruits consumed by the Yellow-chevroned Parakeet.


Resting Metabolic Rates of Adult Northern Shrikes (Lanius excubitor) Wintering in Northern Wisconsin
James D. Paruk, Sheldon J. Cooper, Anna O. Mangan, Ryan S. Brady and Logan Tucker

Abstract
Resting metabolic rate (RMR) represents a significant component of an animal’s energy budget and is correlated with ecological, physiological, and life-history parameters. We measured resting metabolic rates of 14 adult Northern Shrikes (Lanius excubitor) wintering in northern Wisconsin (Ashland and Bayfield Counties) over a 2-year period (Jan–Apr 2008 and 2009). The average (±SE) RMR was 3.09 ± 0.45 ml O2/g/hr (range 2.46–3.83) from the first reported RMR values for adults of this species from the Neartic. Our RMR values were 50% higher than RMRs gathered from summer adult Northern Shrikes in the Paleartic. These data suggest Northern Shrikes exhibit seasonal variation in their RMR as a potential means of winter acclimatization.


Breeding Biology of the Rufous-backed Robin (Turdus rufopalliatus) in an Urban Area Outside its Original Distribution Range
Carbo-Pilar Ramirez , Rodrigo A. Gonzalez Arrieta and Iriana Zuria

Abstract
The Rufous-backed Robin (Turdus rufopalliatus) is a bird endemic to the Pacific slope of Mexico and the Balsas Basin, and is currently expanding its distribution range to the Mexican Central Highlands, occupying urban areas. Its breeding biology is poorly known in its original distribution range and unknown in the newly colonized areas. We present a description of its breeding biology in one of the newly colonized areas, including nest site selection, nest composition, clutch size, eggs and incubation period, hatching and nestling success, and observations on behavior of adults and nestlings. The study was conducted in 2013 in an urban area of central Mexico, specifically at the main campus of Universidad Autónoma del Estado de Hidalgo, in Pachuca, Hidalgo. Nests were built on trees at a mean height of 5.66 ± 0.51 m. The nest was generally a shallow cup made of vegetable material reinforced with mud. Mean clutch size was 2.75 ± 0.16. Eggs were light to medium blue with reddish-brown markings. Incubation period lasted around 13 days. Hatching success was on average 1.88 ± 0.35. Nestlings remained 14 days in the nest before they fledged. The nests, eggs, and behavior have some characteristics similar to those of other thrushes, including individuals of the same species in their original distribution range. We discuss the implications of including anthropogenic materials in nest construction and present the first case of fledgling entanglement with synthetic materials at the nest for T. rufopalliatus.


Notes on Nest and Chicks of the Guianan Red Cotinga (Phoenicircus carnifex) in Amazonas, Brazil
Felipe Bittioli R. Gomes, Gabriel Augusto Leite and Christian Borges Andretti

Abstract
The Guianan Red Cotinga (Phoenicircus carnifex) is a poorly known member of the family Cotingidae, and information concerning its biology, ecology, and natural history are scarce. We provide the first description of the nest and young of the Guianan Red Cotinga and provide additional natural history data on its diet and habitat preferences.


Infanticide on a Grown Nestling in a Sparse Population of Japanese Barn Swallows (Hirundo rustica gutturalis)
Masaru Hasegawa and Emi Arai

Abstract
Direct evidence of infanticide is still scarce, which prevents understanding the evolutionary and ecological importance of infanticide. In Barn Swallows (Hirundo rustica) all direct evidence of infanticide has been gained from nestlings a few (≤4) days after hatching and mostly from colonial breeders. Here, we report the infanticide of a 17-day-old nestling by a mated male Barn Swallow in a sparse Japanese population, demonstrating that infanticide is not confined only to small nestlings. In sparse populations where preferable nest sites are limited, selection may favor infanticide to occupy good nest sites even if it entails substantial handling costs.


Do Urban American Crows (Corvus brachyrhynchos) Contribute to Population Declines of the Common Nighthawk (Chordeiles minor)? 
Steven C. Latta and Krista N. Latta

Abstract
Ground-nesting Common Nighthawks (Chordeiles minor), adapted to living and reproducing in North American cities, nest on flat-topped gravel roofs. But populations of Common Nighthawks have declined in recent years throughout their range. One hypothesis to explain these declines is that American Crows (Corvus brachyrhynchos), which have increased dramatically in numbers in urban areas in recent years, may be depredating nighthawk nests. If urban crows are a factor in nighthawk declines, we predicted there would be higher rates of predation on nests in urban areas than in rural areas. We tested this hypothesis by placing and monitoring artificial nests containing Coturnix quail eggs in both urban and rural settings. Depredation of experimental clutches was significantly lower in rural, natural habitats than in the urban environment. The type of substrate on urban roofs may also be important in influencing rates of depredation, as egg-loss was more common at experimental nests on roofs with a small pea gravel substrate than on roofs covered in larger river stone. In all cases, identified predators were American Crows. While experimental predation rates may not represent actual levels of predation on natural nests, these relative differences in rates of predation suggest that urban crows may be an important contributor to declining populations of Common Nighthawks.


First Documentation of a “Double-Decker” Cerulean Warbler (Setophaga cerulea) Nest
Claire E. Nemes, Kamal Islam and Daniel M. Pirtle

Abstract
Construction of nests containing multiple layers or “stories” has been observed in a number of passerine species. These atypical nest structures are frequently a response to brood parasitism, wherein the host female will bury the parasite’s egg under a new layer of nesting material. They may also occur as a result of either intra- or interspecific competition for limited nest sites, with one individual usurping another’s nest and adding new material on top. However, such structures have not previously been documented in the Cerulean Warbler (Setophaga cerulea), a Neotropical migrant species that breeds in the eastern U.S. and Canada. Here, we report our observations of an unusual “double-decker” nest that was constructed in 2014 in Brown County, southern Indiana. A female Cerulean Warbler first built a typical nest, and several days later we discovered a second visibly distinct nest superimposed on top of the original one. Subsequent retrieval and inspection of the two-story nest revealed no buried egg or other definitive evidence of Brown-headed Cowbird (Molothrus ater) parasitism, which is known to occur in this species. The second story may have been built by a second female who usurped the original nest, but too few birds in our study population were banded for us to distinguish between females. Consequently, the reason for the second story remains unclear because of the unique breeding biology of this canopy-dwelling species, which makes observing nesting activity a challenge.


Nest Defense by a White-rumped Shama (Copsychus malabaricus) Against Snakes
Rui-Chang Quan and Huan Li

Abstract
Snakes represent a serious nest predator to birds. We describe detailed information about interactions between the White-rumped Shama (Copsychus malabaricus) and a nest predator, the Cantor’s Kukri Snake (Oligodon cyclurus) using video recordings. We observed a female White-rumped Shama defending its nest from a Cantor’s Kukri snake by pecking at it when it came within 1 m of the nest. One snake was driven away without consuming a nestling. Two subsequent visits by a larger snake also ended with the snake leaving, but in each attack the snake successfully consumed one nestling. In comparison to findings of an immediate response of other passerines fleeing nests upon snake incursion and subsequent anti-predator attacks, the female shama in this observation attacked the snake predator immediately at its first appearance at the nest.


Sugar Packet Opening by Noisy Miners (Manorina melanocephala): A Novel Foraging Behavior
Carlos A. Delgado-V and Juana C. Correa-H

Abstract
In 2013 and 2014, Noisy Miners (Manorina melanocephala) were observed consuming a human-provided food source. We describe here how individual Noisy Miners manipulated, opened, and fed from sugar packets found at an outdoor cafe. This is the first published observation of this behavior in this species. Further systematic observations of this feeding behavior are necessary to ascertain how frequent and localized this event is in this species of honeyeater.


Unusual Behavior in Parental Care by a House Wren (Troglodytes aedon): Post Fledging Use of an Old Nest During Cold Nights
Micah N. Scholer

Abstract
I report on the unusual behavior of an adult House Wren (Troglodytes aedon) leading recently fledged young back to the nest for two consecutive nights. The ambient temperature reached below 0°C during both nights. Despite disadvantages associated with remaining in the nest, this observation suggests that adult birds may assess trade-offs between perceived risks versus the benefits of engaging in other activities, in this case roosting communally for thermoregulation.


The Correct Name of the Curl-crested Aracari (Pteroglossus beauharnaisii) and the Date of Its Publication
Rick Wright

Abstract
The original description and name of the aracari currently known as Pteroglossus beauharnaesii Wagler 1832 have been inexplicably overlooked. By priority, the correct name and author citation is in fact Pteroglossus beauharnaisii Wagler 1831.


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