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Friday, 6 May 2016

The Wilson Journal of Ornithology March 2016, Volume 128 Issue 1

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

Table of Contents
Mar 2016 : Volume 128, Issue 1 



The Blue-headed Quail-Dove (Starnoenas cyanocephala): an Australasian dove marooned in Cuba
Storrs L. Olson and James W. Wiley

We review the taxonomic history, external morphology, anatomy, behavior, distribution, and zoogeography of the Blue-headed Quail-Dove (Starnoenas cyanocephala), which is endemic to Cuba, and conclude that it is completely unlike any other New World member of the Columbidae. It presents a mosaic of characters shared with various genera in Australasia but is perhaps most similar to the Australian genus Geophaps and related terrestrial pigeons. The Blue-headed Quail-Dove should be placed in its own subfamily, Starnoenadinae, until its relationships with Australasian genera can be refined by additional data including molecular. We recommend that the English name be changed to Blue-headed Partridge-Dove.

Morphological and genetic variation of the Yellow-backed Oriole (Icterus chrysater) across its widely disjunct distribution in Central America 
Maria Nandadevi Cortes-Rodriguez, Rachel J. Sturge and Kevin E. Omland

Geographic barriers between populations of a species can result in divergence of genes, morphology, or behaviors that can lead to speciation. The Yellow-backed Oriole (Icterus chrysater) is distributed from southern Mexico to Colombia, but with a major range disjunction of 600 km in Costa Rica. We examined molecular and morphological data for differences between northern and southern populations. We sequenced the mitochondrial control region and six nuclear introns. Genetic data show strong north–south population structure with evidence of gene flow. The evidence of gene flow between populations is surprising because of the large geographic break between populations. We also measured six morphological characters from specimens collected along the species’ distribution and found shallow north–south divergence.

What determines the timing and duration of the nesting season for a tropical dry forest bird, the White-throated Magpie-Jay (Calocitta formosa)?
Tom A. Langen and Elena C. Berg

The factors affecting the timing of nesting in tropical birds remain poorly understood. We investigated the phenology of White-throated Magpie-Jay (Calocitta formosa) nesting in the dry forest of northwest Costa Rica, a region characterized by a severe 5-month dry season followed by a very rainy wet season. We examined whether nesting was associated with climate, diet, risk of parasite infection to nestlings, risk of nest predation, and opportunity to re-nest. Groups of White-throated Magpie-Jays nested repeatedly, initiating nests over a 7-month period that spanned the transition from the dry to early wet season. The diet of adults and the composition of food fed to broods varied seasonally in parallel with changes in vegetation condition and climate associated with the transition from dry to wet season. Fledgling transition to nutritional independence occurred exclusively in the wet season when caterpillars and other arthropods were a large component of the diet. The timing of groups’ last nests was associated with an increase in nestling infections by Philornis botflies. We argue that progress at understanding tropical birds’ nesting seasons will be made by looking beyond diet and climate at the time of nesting, to additional factors such as the conditions during the post-fledging period of offspring development, temporal patterns of risk of parasite and pathogen infection to nestlings, and temporal patterns of nest or fledgling predation risk.

Weather influences on nest success of the endangered Puaiohi (Myadestes palmeri)
Jean Fantle-Lepczyk, Andrew Taylor, David Duffy, Lisa H. Crampton and Sheila Conant

The endangered Puaiohi (Myadestes palmeri) endemic to Kaua‘i is the island’s only remaining native thrush. Given its small population of ~500 birds, it is essential to understand conditions that affect the species’ recruitment and survival. Previous observations of Puaiohi suggested that weather may influence nest success and productivity, but no studies investigated this relationship empirically. Our goal was to investigate potential links between weather conditions (precipitation and temperature) in the Puaiohi’s range (~20 km2) and several measures of reproductive success, using published data from 1996–1998 and new data collected by the Kaua‘i Forest Bird Recovery Project from 2007–2009. Total rainfall in the previous wet season strongly and positively correlated with the majority of the nest success variables (three of four). Mean rainfall during the breeding season correlated positively with reproductive effort (attempts/season and length of breeding season) and with total reproductive output, but there was some evidence that too many rainy days during the peak breeding season associated with fewer young fledged per nesting attempt. Although there seem to be clear implications that weather affects reproductive output of Puaiohi, results from longer time series will be useful in refining this relationship. Given that prevailing weather conditions of the Puaiohi’s range may shift with anthropogenic climate change, which in turn may alter the severity and frequency of El Niño Southern Oscillation events, our findings provide insight into future trends in reproductive output, and thus, population of this endangered species.

Molt patterns, age criteria, and molt-breeding dynamics in American Samoan landbirds 
Peter Pyle, Keegan Tranquillo, Kimiko Kayano and Nicole Arcilla

We examined 135 specimens and analyzed 1,735 captures of indigenous American Samoan landbirds, of nine target species in seven families, to document molt patterns, assess the extent of molt-breeding overlap, and present criteria to determine age. Preformative molts varied from absent to complete, and there was no confirmed evidence for prealternate molts. Molt strategies, age-determination criteria, and remigial replacement sequences were largely consistent with those of other temperate and tropical bird species within the same families. Suspended and/or arrested molts were recorded in seven species and staffelmauser or stepwise molt in two species, including the first report in a passerine. Our data suggest that staffelmauser and suspension of molt in passerines may share a common underlying mechanism. Despite broad overlap of breeding and molting seasons at the population level, we observed little evidence of molt-breeding overlap at the individual level. We suggest that molt and accompanying restoration processes may take precedence over breeding, as indicated by well-defined molting seasons despite apparent year-round or bi-modal breeding in some of our species. Tropical landbird species appear to be capable of suspending molt to breed when environmental conditions shift to facilitate successful reproduction.

Preformative molt adjustment in phenologically divergent populations of the Lesser Goldfinch (Spinus psaltria) 
William L. Rockey

The extent to which birds invest in a variable molt reflects the interplay between life history phenology and environmental conditions. This study assesses geographic variation in the preformative molt of the Lesser Goldfinch (Spinus psaltria) by comparing molt patterns between the Pacific and interior populations of North America which differ in life history phenology by 2 months. Both populations exhibited a strong bimodal pattern in primary replacement where individuals either replaced none or ≥3 primaries. Among individuals that replaced >0 remiges, males molted significantly more remiges than females. The earlier breeding Pacific population contained a significantly greater proportion of individuals that replaced >0 remiges and a significantly greater proportion of individuals that replaced >0 primaries. These results provide observational evidence in support of the early breed – extensive molt hypothesis, which states that the preformative molt is adjusted in response to different photoperiod exposure because of later hatch date. Further experimental research is required to validate this hypothesis.

Song structure and cadence of the Veery (Catharus fuscescens) in the Appalachian Mountains 
Courtney L. Brennan and Andrew W. Jones

We recorded the natural song of male Veeries (Catharus fuscescens) on breeding territories to examine variation in song structure, repertoire size, and patterns of song delivery. Despite wide distribution of Veeries, many aspects of their biology are largely unknown, including a clear characterization of song and singing behavior. Recordings were made in four regions through the Appalachian Mountains in the USA. Visual analysis of song spectrogram images revealed that Veeries present their song repertoires in an oscillating frequency pattern, a previously undocumented feature of their singing behavior. Analysis showed Veeries’ repertoire ranges from 1–6 different song types, which is larger than what was previously described in the literature. Spectrogram analysis suggested that Veeries present song repertoires in predictable patterns, and patterns of song presentation can change depending on repertoire size. Songs and singing behavior did not differ between dawn and dusk singing bouts.

Long incubation off-bouts of females paired with colorful males in Barn Swallows (Hirundo rustica) 
Masaru Hasegawa and Emi Arai

Among several types of parental care behavior, incubation behavior in passerine birds offers an ideal opportunity to study the link between female parental care and male ornamentation, because males generally lack an incubation patch, and thus rarely incubate. Although preceding studies have focused mainly on on-bout duration (or its total amount, i.e., nest attentiveness), it has recently been established that off-bout durations, independent of on-bout durations, are also important for embryo development and thus for efficient incubation. Using Barn Swallows Hirundo rustica, we found that the duration of female incubation off-bouts increased with a sexually selected trait, male throat coloration, independent of female nest attentiveness. A longer female off-bout was positively correlated with the incubation period, indicating that colorful males had reproductive disadvantage because of their mates’ inefficient incubation. Together with a previous study in which females demonstrated a higher amount of incubation when their mates had large white tail spots, another sexually selected trait, our findings indicated that the different aspects of parental care are differently related to male ornaments. Multiple aspects of parental care should be considered when examining the reproductive (dis)advantage of male ornamentation during parental care.

American Robins (Turdus migratorius) and Cedar Waxwings (Bombycilla cedrorum) vary in use of cultivated cherry orchards
Rachael A. Eaton, Catherine A. Lindell, H. Jeffrey Homan, George M. Linz and Brian A. Maurer

Some fruit-eating bird species commonly consume cultivated fruit. Species-specific variation in diet preferences could result in varying use of orchards and impacts on the fruit-producing industry. However, species-specific studies of avian orchard use are lacking, particularly throughout the fruit-growing season. Our objectives were to quantify the frequency of daily bird visits to orchards and the amount of time birds spent visiting orchards each day over the fruit-ripening season. Birds are well-documented consumers of cultivated sweet cherries (Prunus avium), which are relatively high in sugar and low in proteins and lipids. American Robins (Turdus migratorius) and Cedar Waxwings (Bombycilla cedrorum) are common fruit-consumers in sweet cherry orchards. Robins often consume larger proportions of invertebrates and prefer lipid-rich fruits, while waxwings choose sugary fruits. Given these species-specific diet differences, we hypothesized waxwings would spend a greater proportion of days and more time each day in cherry orchards, compared to robins. We used radio telemetry to track the habitat use of 25 American Robins and 17 Cedar Waxwings in sweet cherry orchards of Michigan. Over their respective radio-tracking periods, waxwings visited orchards a greater percentage of days than robins (waxwings: mean  =  21%, SD  =  22; robins: mean  =  6%, SD  =  4). In addition, waxwings visited orchards for more time each day. Differences in diet preferences and nutritional physiology may translate into species-specific patterns of habitat use for birds in fruit-rich environments.

Factors affecting nest survival of Henslow's Sparrows (Ammodramus henslowii) in southern Indiana
Shawn M. Crimmins, Patrick C. McKann, Joseph R. Robb, Jason P. Lewis, Teresa Vanosdol, Benjamin A. Walker, Perry J. Williams and Wayne E. Thogmartin

Populations of Henslow’s Sparrows have declined dramatically in recent decades, coinciding with widespread loss of native grassland habitat. Prescribed burning is a primary tool for maintaining grassland patches, but its effects on nest survival of Henslow’s Sparrows remains largely unknown, especially in conjunction with other factors. We monitored 135 nests of Henslow’s Sparrows at Big Oaks National Wildlife Refuge in southern Indiana from 1998–2001 in an effort to understand factors influencing nest survival, including prescribed burning of habitat. We used a mixed-effects implementation of the logistic exposure model to predict daily nest survival in an information theoretic framework. We found that daily survival declined near the onset of hatching and increased with the height of standing dead vegetation, although this relationship was weak. We found only nominal support to suggest that time since burn influenced nest survival. Overall, nest age was the most important factor in estimating daily nest survival rates. Our daily survival estimate from our marginal model (0.937) was similar to that derived from the Mayfield method (0.944) suggesting that our results are comparable to previous studies using the Mayfield approach. Our results indicate that frequent burning to limit woody encroachment into grassland habitats might benefit Henslow’s Sparrow, but that a variety of factors ultimately influence daily nest survival. However, we note that burning too frequently can also limit occupancy by Henslow’s Sparrows. We suggest that additional research is needed to determine the population-level consequences of habitat alteration and if other extrinsic factors influence demographics of Henslow’s Sparrows.

Predators of bird nests in the Atlantic forest of Argentina and Paraguay 
Kristina L. Cockle, Alejandro Bodrati, Martjan Lammertink, Eugenia Bianca Bonaparte, Carlos Ferreyra and Facundo G. Di Sallo

Predation is the major cause of avian nest failure, and an important source of natural selection on life history traits and reproductive behavior. However, little is known about the identity of nest predators in much of the world, including the Neotropics. To identify some of the nest predators exerting selection pressure on birds of the subtropical Atlantic forest, we present observations of animals depredating bird nests in Argentina and Paraguay. We recorded depredations (destruction or removal of eggs or nestlings) at 33 nests of 25 species of birds, confirming as predators ten species of birds (Squirrel Cuckoo Piaya cayana, White-eared Puffbird Nystalus chacuru, Toco Toucan Ramphastos toco, Red-breasted Toucan Ramphastos dicolorus, Saffron Toucanet Pteroglossus baillonii, Chestnut-eared Aracari Pteroglossus castanotis, Planalto Woodcreeper Dendrocolaptes platyrostris, White-throated Woodcreeper Xiphocolaptes albicollis, Buff-browed Foliage-gleaner Syndactyla rufosuperciliata, and Plush-crested Jay Cyanocorax chrysops) and two species of medium-sized mammals (White-eared Opossum Didelphis albiventris and Crab-eating Fox Cerdocyon thous), and inferring two additional mammal species (Black Capuchin Monkey Sapajus nigritus and Southern Tigrina Leopardus guttulus). Fifty-five percent of these nests were depredated by toucans or aracaris (Ramphastidae), which destroyed eggs and nestlings at cup-, closed- and cavity-nests. Red-breasted Toucans destroyed nests 1.6–22 m high, in habitats ranging from primary forest to a backyard. Mammals and jays depredated nests from ground-level to midstory, whereas woodcreepers and aracaris depredated nests from the midstory to canopy. We did not record snakes at any bird nests, in strong contrast to studies from other Neotropical forests. Further studies should examine trade-offs among nest concealment, physical protection, and parental defense behavior as means of reducing nest predation, and use camera traps to quantify nest predation rates by predator species.

Effects of variation in nestling hunger levels and begging on the provisioning behavior of male and female Eastern Phoebes (Sayornis phoebe)
C. Adam Heist and Gary Ritchison

Nestling birds solicit food from their parents using conspicuous vocalizations and visual begging displays, and evidence suggests begging represents an honest signal of need that adults use to determine provisioning rates. Less is known about how adult males and females may differ in response to changes in nestling begging behavior as a result of variation in hunger levels or how nestling begging and adult provisioning may vary seasonally in multi-brooded species. To examine these parent-offspring interactions, we manipulated hunger levels of nestling Eastern Phoebes (Sayornis phoebe) during the 2011 breeding season in central Kentucky. Both first and second broods were divided into three treatments: whole brood fed (n  =  12), whole brood deprived (n  =  16), and some fed/some deprived (split; n  =  14). Food-deprived nestlings begged with increased intensity, and fed broods begged with less intensity. Adult Eastern Phoebes adjusted their provisioning rates accordingly, provisioning food-deprived nestlings at higher rates than fed and split broods. These results suggest that nestling begging is an honest signal of hunger and parents respond to variation in nestling begging by adjusting their provisioning behavior. Provisioning rates of male and female phoebes did not differ, but post-treatment responses of adults differed for first and second broods. For both first and second broods, adults reduced provisioning rates to nestlings in fed and split broods. However, food-deprived nestlings in first broods were fed at similar rates before and after treatment, whereas food-deprived nestlings in second broods were provisioned at much higher rates after treatment. Differences in the provisioning of first and second broods may represent a trade-off between investment in current and future reproduction.

Flight of Black-Necked Cranes (Grus nigricollis) with legs drawn up: behavioral responses to low temperature and duration of exposure 
Dejun Kong, Fengshan Li, Qiang Liu, Xingyao Zhong and Xiaojun Yang

Weather conditions considerably influence the behavior of wildlife, particularly those living in harsh habitats such as the plateau. In this study, we reported unusual flight behavior of Black-necked Cranes (Grus nigricollis) where legs are drawn up. Among 15 crane species, it is the only species that spends its entire life in alpine areas. Field observations were conducted during the three winters of 2006/07, 2009/10, and 2012/13 at Dashanbao National Nature Reserve (DNNR), northeastern Yunnan, China. At the population level, ~4% of Black-necked Cranes displayed this behavior, whereas a total of 156 individuals from 49 flocks displayed this behavior among the clearly observed 4,007 individuals of 751 crane flocks. Our results showed a strong negative correlation between prevalence of this behavior and departure temperature (r  =  −0.832, P  =  0.005, n  =  9). Moreover, the average temperature of the preceding 12 hrs and duration of exposure to subzero temperature had a significant effect on the occurrence of leg-drawn-up flight behavior (P < 0.05), whereas the extreme low temperature of the preceding 12 hrs did not significantly affect the prevalence of this behavior (F1,3  =  1.974, P  =  0.26). We inferred that this infrequent flight posture developed as a behavioral response to the low air temperature and duration of exposure.

Migration of Red-tailed Hawks (Buteo jamaicensis) from northwest Wyoming
Derek Craighead, Ross H. Crandall, Roger N. Smith and Steven L. Cain

While a common species throughout most of the United States, little is known on the migration habits of Red-tailed Hawks (Buteo jamaicensis). From 1999–2002, we tracked 16 adult Red-tailed Hawks from their breeding grounds in northwest Wyoming using Argos PTT transmitters. Our objectives were to identify dates and duration of migratory movements, stopover sites, and identify migration routes and wintering areas. We found the mean migration initiation date from the breeding area was 13 October, mean fall migration duration including stopovers was 23.3 days, mean distance of fall migration was 2489.6 km, and mean end date of fall migration was 5 November. Wintering locations were in Mexico and ranged from the southern Mexican state of Chiapas north to Sonora and Chihuahua. The mean number of days spent on the wintering grounds by tracked hawks was 133.1. The mean departure date from wintering grounds to breeding areas was 17 March, mean spring migration duration including stopovers was 22.1 days, mean end date of spring migration was 8 April, and mean distance of spring migration was 2 490.3 km. Most birds made stopovers during both fall and spring migration which varied in location and duration. Using satellite telemetry, we identified wintering locations of Red-tailed Hawks breeding in northwest Wyoming and confirmed a leapfrog migration pattern with no concentrated migration routes from the breeding area to non-breeding areas.


Pseudogenisation of the Short-wavelength Sensitive 1 (SWS1) Opsin Gene in Two New Zealand Endemic Passerine Species: the Yellowhead (Mohoua ochrocephala) and Brown Creeper (M. novaeseelandiae)
Andrew E. Fidler, Zachary Aidala, Michael G. Anderson, Luis Ortiz-Catedral and Mark E. Hauber

Perception of ultraviolet (UV) light, mediated by the avian short-wavelength sensitive-1 (SWS1) opsin, is important for birds in a range of functional contexts, including foraging, mate choice, and offspring recognition. The maximum absorption wavelength of avian SWS1 opsins can shift in and out of UV wavelengths because of residue changes at functionally critical positions in the SWS1 second transmembrane domain. Indeed sequencing of a short SWS1 gene ‘spectral tuning’ coding region allows assignment of avian vision as either ultraviolet sensitive (UVS) or violet sensitive (VS). Here, we report frameshift mutations in the SWS1 ‘spectral tuning’ regions of two endemic New Zealand passerine species: the Yellowhead or Mohua (Mohoua ochrocephala) and the Brown Creeper or Pipipi (M. novaeseelandiae). The findings indicate a total absence of functional SWS1 opsins in these two species in contrast to their congeneric, the Whitehead or Popokotea (M. albicilla) which is predicted to have UVS vision. Associated alternations in light perception might have critical implications for color-associated behaviors in these two Mohoua species, including discrimination of their own eggs from those of the genus’ specialist brood parasite, the Pacific Long-tailed Cuckoo or Koekoea (Urodynamis taitensis). In combination with recent evidence for frameshift based loss of opsin functioning in penguins, we suggest that loss of opsin function in avian lineages may be more widespread than previously assumed and may be of adaptive significance.

Assessment of the Birds of Swains Island, American Samoa
Andrew J. Titmus, Nicole Arcilla and Christopher A. Lepczyk

Swains Island is an uninhabited 210 ha former copra plantation 360 km North of American Samoa. The island, dominated with coconut palm (Cocos nucifera), was last surveyed in 1976. The goal of this 17–26 September 2012 survey was to identify the bird species present, and document relative abundance, distribution, and breeding activity across the island. Two shoreline surveys recorded a seabird community dominated by Black Noddy (Anous minutus), White Tern (Gygis alba), and Brown Noddy (Anous stolidus), while the reef flat community was dominated by Pacific Golden Plover (Pluvialis fulva) and Wandering Tattler (Tringa incana). Inland surveys revealed four roosting or breeding species, including Black Noddy, White Tern, Brown Noddy, and Red-footed Booby (Sula sula). Seabird densities were highest in the northwest section of the island, furthest from former settlements. Although feral pigs (Sus scrofa) were recently eradicated, feral cats (Felis cattus) remain present, and Pacific rats (Rattus exulans) were observed over all island sections, likely posing threats to seabird populations. Predator control and restoration of preferred nesting tree species would likely increase seabird populations.

Social and Spatial Reintegration Success of New Caledonian Crows (Corvus moneduloides) Released after Aviary Confinement
Gavin R. Hunt

Wild birds are sometimes brought into captivity in order to conduct more controlled experiments, then released. Follow up work investigating how successful these birds are at reintegrating into their original habitats are rare. Here, I investigate the reintegration success of 13 New Caledonian Crows (Corvus moneduloides) who spent from 4–210 days in a large outdoor aviary in 2012 and 2014, then were released at their capture site. Five of the crows were monitored by telemetry for 2 weeks after their release in November 2014. In March and April 2015, 12 of the 13 crows were recorded at feeding sites where they were captured. The released crows showed a high degree of site fidelity and appeared to rapidly reintegrate with resident crows in the area. There were two cases of released crows successfully breeding. Long-term stay in captivity appears to have minimal impact on the ability of sub-adult and adult crows to re-establish their wild lifestyles, but juvenile crows <1 year old may find it more difficult to reintegrate after extended periods in captivity.

Breeding Patterns of Asian Horned Larks (Eremophila alpestris nigrifrons) on the Tibet Plateau
Shaobin Li, Cheng Guo and Weijun Peng

Horned Larks (Eremophila alpestris) occur widely across North America, Europe, and central Asia. Knowledge of the breeding biology of Asian Horned Larks is minimal, especially for those populations found at high altitudes. Here, we report breeding patterns of this species at 3,400 m in alpine grasslands of the northeastern Tibetan plateau. Horned Larks are resident throughout the year at our study site. The mating system is social monogamy; nests are built on the ground by the female alone and territories are intensely defended during the breeding season. Clutches are initiated from late April to mid-July, during which a pair may make two nesting attempts. Clutch size averaged 2.52 eggs, and brood parasitism was never observed. Incubation was undertaken by females and lasted 12.4 days; young in the nest were fed by both parents for 9.9 days. Nest success calculated by the Mayfield method was 13.7%. Seasonal variation existed for vegetation height, egg and clutch size, and nest success. Taller vegetation was often associated with more food availability and better nest concealment later in the season, and consequently led to larger clutch size and greater nest success as the season progressed. Compared with low-altitude populations in North America, high-altitude Horned Larks started breeding later, produced fewer but larger eggs, and had a longer nestling period, which suggests that they allocate more energy per offspring as a way to compensate for the harsh conditions and to enhance nest success in high elevation ecosystems.

Lethal Agonistic Behavior between Two Male Magellanic Woodpeckers Campephilus magellanicus Observed in the Cape Horn Area
Gerardo E. Soto, Pablo M. Vergara, Ashley Smiley, Marlene E. Lizama, Darío Moreira-Arce and Rodrigo A. Vásquez

Agonistic behavior in woodpeckers has been described for a wide range of species, although previous studies have not reported aggressive encounters resulting in the death of adults. In this study, we provide the first evidence of lethal agonistic behavior between two male Magellanic Woodpeckers (Campephilus magellanicus) inhabiting Patagonia. This species is commonly regarded as the largest extant Campephilus woodpecker. The agonistic encounter was video recorded within the core territory of the dead individual and his mate, a previously banded and monitored pair, as part of a monitoring research on this species carried out during the last 2 years. A week after the fight, we recorded a non-banded young male Magellanic Woodpecker accompanying the dead individual’s mate. This young male Magellanic Woodpecker is potentially the offspring of the former pair or perhaps a new mate replacing the dead individual. From this observation, we deduced that the previously occupied territory of the dead individual, as well as its breeding role, was subjected to reallocation by competing adjacent woodpecker families. This mortality event offers novel insight into the behavior of Magellanic Woodpeckers and suggests that lethal agonistic behavior likely could contribute to territory plasticity and family structure in this species.

Nest Architecture, Clutch Size, Nestling Growth Patterns and Nestling Attendance of the Fire-eyed Diucon (Xolmis pyrope) in North-Central Chile
Esteban Botero-Delgadillo and Rodrigo A. Vásquez

We present descriptions of nest architecture, clutch size, nestling growth and nestling attendance for the Fire-eyed Diucon (Xolmis pyrope), based on nests found at the Fray Jorge National Park, Chile, at the northernmost part of its distribution. Nests were cup-shaped structures averaging 283.5 ± 26.6 mm in width and 123.1 ± 6.8 mm in height (n = 5), found in matorral steppe habitat and Olivillo humid forest relicts. Nests contained 2–3 eggs. Nestling growth in Fray Jorge’s nests was nearly two times slower than in populations from central Chile, as suggested by our calculations of the constant rate (K = 0.277) and the T10-90 period (12.9). During 20 hrs of video recording, the breeding adults spent a total of 3.4 hrs at the nest. Both parents attended the nest, and the rates of visits, nestling provisioning and fecal sac removal increased with nestling development. We observed that adults can still care for the young at least 2 weeks after fledging, covering an area of 2.3 ha while searching for food. This information could be valuable for further studies on geographic variation in the species’ behavioral ecology.

Consumption of Müllerian Bodies by Golden-olive Woodpecker (Colaptes rubiginosus) in Nicaragua’s Highlands
Marvin A. Tórrez, Wayne J. Arendt and Luis Díaz

The Golden-olive Woodpecker is a generalist species found in a wide range of habitats, being particularly common in coffee plantations within Nicaraguan cloud forests. Observations of an individual feeding at the base of Cecropia leaves revealed it was consuming Müllerian bodies that the Cecropia produces to feed Azteca ants as part of a host-inhabitant mutualistic symbiosis. This record further documents the plasticity of some species as they search for alternative sources of energy.

Prothonotary Warblers (Protonotaria citrea) Break Their Beaks During Attacks on Wooden Conspecific Decoys
Morgan C. Slevin, Douglas W. Raybuck and Than J. Boves

Researchers often use wooden conspecific decoys paired with playback of audio recordings to capture individuals of territorial avian species. Agonistic responses elicited by these decoys can be violent at times; however to our knowledge, there have been no previously recorded instances of physical attacks on a decoy causing injury. In April 2014, we witnessed two cases of male Prothonotary Warblers (Protonotaria citrea) breaking their beaks while attacking a conspecific wooden decoy used during target-netting. Upon recapture 6–8 weeks after initial breakage, beak damage had healed and both males’ mass was virtually unchanged (<1% change from their mass at initial capture). We also observed no detrimental effects of the broken beaks on within-season survival, mate attraction, or territory maintenance. Despite the lack of effect of the breakage on the birds, we suggest the use of softer materials in decoys. In addition to the development of safer practices when target-netting, our observations draw attention to the potential dangers of territorial disputes in passerines as well as the importance of territorial signaling to avoid serious injury.

Eurasian Collared-Dove (Streptopelia decaocto) Usurps Nest of American Robins (Turdus migratorius)
Andrew C. Kasner and D. Niler Pyeatt

Interspecific nest usurpation was observed when a Eurasian Collared-Dove (Streptopelia decaocto) took over the nest of an American Robin (Turdus migratorius) in Plainview, Hale County, Texas in April 2014. The nest was constructed and occupied by an American Robin, briefly shared by a Eurasian Collared-Dove over a period of 3 days, and then aggressively taken over by the collared-dove. The collared-dove pair fledged two young in May 2014. This represents a first record of interspecific nest usurpation by Eurasian Collared-Dove. Interspecific nest piracy by this invasive species has implications for songbird conservation if the behavior proves to be frequent.

Timing of Songbird Nest Predation as Revealed by Video Surveillance 
Ryan A. Gill, W. Andrew Cox and Frank R. Thompson III

The use of video to monitor nests has increased in frequency over the past 25 years and new research using this technology has shed light on many aspects of the interactions between predators and nesting birds. We used video cameras to describe the timing of nest predation events for Acadian Flycatchers (Empidonax virescens), Indigo Buntings (Passerina cyanea), and other forest-dwelling songbird species. Seventy-four percent (111 of 151) of nest predation events occurred during diurnal hours for both focal species. Although some of our observations were unexpected (e.g., Barred Owls [Strix varia] were primarily diurnal nest predators), many of the predator-specific temporal patterns we observed were consistent with prior knowledge. Understanding diel patterns of nest predation in conjunction with identification of the suite of predators that contribute to overall predation rates will improve our understanding of how birds recognize and respond to the risk of nest predation across ecological and evolutionary time scales.

Photographic Evidence and Chronology of Nest Parasitism by a Wild Turkey (Meleagris gallopavo)
Kathryn J. Brautigam, Douglas C. Osborne and Don White Jr.

Accounts of obligate nest parasitism (e.g., Brown-headed Cowbird, Molothrus ater) are common in the literature; however, reports of facultative nest parasitism are less frequent. Nest parasitism has been documented only rarely in Wild Turkeys (Meleagris gallopavo). We obtained photographic evidence of a female Wild Turkey parasitizing an artificial ground nest in Lincoln County, Arkansas, in June 2013. A series of photographs show the turkey finding the nest, moving the eggs 0.3 m from the original nest location, returning twice the following day, and parasitizing the nest by laying a single egg. The actual parasitism event occurred 33–55 hrs after the turkey discovered the nest. We are unaware of other published photographs documenting nest parasitism by Wild Turkeys and this series of photographs provides information on the chronology of nest parasitism by Wild Turkeys.

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