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Thursday, 9 July 2015

The Wilson Journal of Ornithology June 2015 Volume 127 Issue 2: Abstracts

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

June 2015 : Volume 127 Issue 2 



From passion to science 
Edward H. Burtt, Jr.

We began our ornithological careers out of passion, for watching birds, for identifying them, for sharing our excitement and knowledge with our friends. At some point our desire to know and understand birds led us into science. We joined Christmas Bird Counts and wondered why the species and numbers varied annually. We wondered what characterized good sparrow habitat. We found that special patch and saw more sparrows than any other participant. Then, we discovered that people wrote about and published their observations of birds. We read some of those papers, at first the short ones, those that focused on natural history, on what we could observe. Then we tried to imitate the authors, by watching birds, asking questions and collecting data. We were unaware that the child hobbyist had become the adolescent scientist. I joined the Wilson Ornithological Society and began to prepare my observations for publication. One day I screwed up my courage and submitted a short paper on Tree Swallows (Tachycineta bicolor). It was rejected. But by then I was an undergraduate. I had just received a small research grant. The die was cast. Graduate school followed. I wrote more short papers. Some were published. I synthesized some of these into longer papers with substantive conclusions that were cited by real ornithologists. Imperceptibly, I became a scientist. I began to formulate hypotheses, deduce predictions, collect data, and create new explanations about the evolution of avian color, an aspect of birds that had fascinated me almost since I became aware of birds and painted a papier-mâché duck brilliant white with scarlet feet and bill, and large, blue eyes.
This observation-based entry into a scientific career is very different from a course-based entry in which the future scientist learns a paradigm, is excited and decides to devote her or his career to that scientific discipline. The importance of one’s introduction to science is explored with respect to different disciplines and the way different scientists think about science. Finally, the importance of the observation-based entry into science is explored with respect to the Wilson Ornithological Society, The Wilson Journal of Ornithology, ornithology, and the field sciences generally.


Social behavior and organization of a native chukar (Alectoris Chukar Cypriotes) population
Philip U. Alkon

A 2-year field study of a free-ranging population of Chukar (Alectoris chukar cypriotes), occupying Mediterranean habitat in Israel’s Lower Galilee, yielded unique insights on (1) the array and context of specific behaviors of wild birds, (2) the complex dynamics of their social processes, and (3) the interaction of behavioral and population dynamics. Systematic observations of individually marked wild birds clarified the function of several prominent displays (e.g., waltzing as a male courtship display) and vocalizations (e.g., the chuk-ar call as an individual announcement that varied widely in form and function). Behavioral relationships among birds were complex, and Chukars demonstrated individual differences in demeanor and status. Strong social bonds among adult males and brood mates were significant cohesive forces, and adult males exhibited strong site affinities from year to year. Chukars spent autumn and winter in coveys of 10–20 birds having heterogeneous gender and age compositions, and occupied separate but overlapping ranges of 4–8 ha. Adult males displayed and threatened conspecifics more than did females during most seasons, but broody hens were aggressive towards other birds. Overt social interactions were most intense while coveys disbanded in early spring, during breeding, and in post-breeding covey formation. Paired males closely accompanied females within restricted nesting territories, but most left their mates during incubation. Large late-summer aggregations of Chukars occurred at open water and in fallow fields where intense social interactions preceded the establishment of permanent covey ranges. The study population underwent an inverse, density-dependent fluctuation that was mediated by behavioral processes. A low overwintering population in Year 1 exhibited little social strife and no population change preceded an orderly and productive breeding season. The subsequent dense population in Year 2 exhibited heightened social strife in winter, a large decline in numbers with the onset of pairing, considerable disturbance of nesting pairs, and lowered reproductive success.

Habitat preference and survival for western meadowlark (Sturnella Neglecta) fledglings in a contiguous prairie system
Matthew D. Giovanni, Larkin A. Powell, and Walter H. Schacht

Grassland bird populations in North America continue to decline according to count and vital-rate data, highlighting the importance of remaining grasslands. Conservation efforts may be enhanced by understanding fledgling habitat preference and survival in relation to age and ambient temperature. We radio-tracked 46 Western Meadowlark (Sturnella neglecta) fledglings in 2006 and 2007 to evaluate variation in habitat preference and survival in subirrigated meadows of the Nebraska Sandhills, one of North America’s largest contiguous grassland systems. Our research indicates that habitat preference varied with fledgling age and ambient temperature: at higher ambient temperatures, fledglings tended to select sites with deeper litter and shorter vegetation, while younger, mostly flightless fledglings tended to select sites with shallower litter and taller vegetation. We confirmed 23 fatalities, including 8 (35%) from predators, 2 (9%) from haying operations, and 13 (56%) from unknown causes. Seven of the eight (88%) depredated fledglings were tracked to live snakes, including six bullsnakes (Pituophis catenifer sayi). The probability of daily survival (0.981) was high compared to estimates for passerine fledglings in other grassland systems. Survival increased with age and ambient temperature but decreased with litter depth. Prior research indicates prescribed burning can decrease litter depth and associated abundance of snakes in grasslands, but neither are likely conservation strategies in subirrigated meadows of the Nebraska Sandhills, because hay production provides winter feed for cattle. We recommend maintaining mid to late summer hay harvest so first cohorts of nestlings can fledge, attain flight, and evade machinery.

Habitat use by grassland birds in natural areas and soybean fields in southern Brazil and Uruguay
Thaiane Weinert Da Silva, Graziela Dotta, Daniel Tourem Gressler, and Carla Suertegaray Fontana

Livestock production and the replacement of semi-natural grasslands by crops result in land use changes and as consequence some habitat is no longer suitable for all species of grassland birds. Although some generalist species could benefit from such changes, habitat alteration is detrimental to the populations of most sensitive species. In this study, we investigated the patterns of habitat use by breeding grassland birds through the assessment of their presence/absence and abundance in a landscape composed of semi-natural grasslands and croplands in southern Brazil and Uruguay. We sampled grassland birds in 160 100-m radius point counts: 80 in a semi-natural grassland dominated landscape and 80 in soybean fields with grassland patches. We classified vegetation cover on a 100-m radius buffer following three classes of land use: semi-natural grasslands, wet grasslands, and soybean fields. We used GLMM to analyze presence/absence and abundance of grassland birds found in the region. Nine species showed a positive response to the semi-natural grasslands and/or wet grassland vegetation cover categories. Five species recorded are of conservation concern. Most of the grassland bird species preferred sites with high semi-natural grassland cover and only one species used primarily soybean fields. Grassland birds required around 80% of semi-natural grassland cover to maintain larger abundances. Research across landscapes and a better understanding of the responses of grassland birds to habitat modification are still needed to establish conservation practices of natural grasslands and their avifauna in southern Brazil and Uruguay.

Reproductive success of Field Sparrows (Spizella Pusilla) in response to invasive Morrow’s Honeysuckle: does Morrow’s Honeysuckle promote population sinks?
Holly M. Mcchesney and James T. Anderson

The bush honeysuckle genus (Lonicera) comprises a suite of invasive shrubs that are naturalized in early successional landscapes throughout many parts of central and eastern United States. Although several studies have connected the use of bush honeysuckle as a nesting substrate to decreased nesting success, few have examined its potential effects on the growth or decline of songbird populations. From 2007–2009, we examined the nesting success of Field Sparrows (Spizella pusilla) in southwestern Pennsylvania old-fields to assess reproductive success based on nesting substrate and the density of Morrow’s honeysuckle (Lonicera morrowii) surrounding the nest site. We used the information-theoretic approach to model nesting success as a response to nest substrate, cover of Morrow’s honeysuckle, midpoint of nesting attempt, and clutch size. Our model indicated that Morrow’s honeysuckle, as a substrate and when found in dense patches surrounding the nests of Field Sparrows, had a negative impact on nesting success. We developed a population model to determine if the measured reproductive success (17% ± 5) could maintain a stable population. Results of the population model yielded 1.21 female offspring/adult female. This was not sufficient to maintain a stable population and resulted in a population sink. A sensitivity analysis indicated that adult survivorship was the most influential parameter in the population model, indicating that although breeding success was important, it was not the primary driver of population stability.

Breeding origins of Northern Shovelers (Anas Clypeata) wintering on the Great Salt Lake, Utah
Anthony J. Roberts and Michael R. Conover

The breeding origin and migratory connectivity of wintering birds are important to address how population changes on wintering areas are impacted by changes elsewhere in the birds’ annual cycle. In addition, identifying important point sources of nutrients used throughout the annual cycle can assist managers in identifying sources of toxins or pathogens. We used stable hydrogen isotope ratios to identify breeding locations of Northern Shovelers (Anas clypeata; henceforth shoveler) wintering at the Great Salt Lake (GSL), Utah. Stable-isotope likelihood-based assignment placed the largest number of shovelers collected during winter on the GSL as breeding in the western US and southern Canada, similar to a small sample size of banding records. Shovelers wintering on the GSL generally did not breed locally or at the northern extent of their breeding range, rather wintering shovelers came from across their nesting range.

Food habits and resource partitioning in a guild of Neotropical swifts
Charles T. Collins

The Coastal Cordillera of Venezuela has a rich avifauna including swifts. The aerial arthropod prey of three species found there, Gray-rumped Swift (Chaetura cinereiventris), Vaux’s Swift (Chaetura vauxi), and White-tipped Swift (Aeronautes montivagus), included spiders plus nine orders and 110 families of insects. Diptera and Hymenoptera were the most numerous prey taxa (>60%) taken by all three swifts. Prey size ranged from 0.5–17.9 mm body length, and averaged 2.69 mm for Gray-rumped Swifts, 2.91 mm for Vaux’s Swifts, and 5.52 mm for White-tipped Swifts. Niche breadth was similar in Gray-rumped and Vaux’s Swifts (2.4 and 3.13), and niche overlap was also high (0.98). Niche breadth was higher in White-tipped Swifts (8.49) and niche overlap was <60 with both Gray-rumped and Vaux’s swifts. Observed elevational differences in foraging habitat and altitudinal foraging zones are proposed as resource partitioning mechanisms for this guild of sympatric aerial insectivores.

Nesting biology of the Red-crested Cardinal (Paroaria Coronata) in south temperate forests of central Argentina
Luciano N. Segura, Bettina Mahler, Igor Berkunsky, and Juan C. Reboreda

Studies on breeding biology in Neotropical birds are crucial for understanding different aspects of their life histories and also for their conservation. We describe the nesting biology of the Red-crested Cardinal (Paroaria coronata) in central Argentina, a common suboscine that inhabits south temperate forests. We monitored 367 nests from October to February 2005–2008. Nest initiation followed a unimodal distribution with a peak in November. Within the forest, no nests were built on exotic tree species. Mean clutch size was 3.05 ± 0.05 eggs and decreased with time within the breeding season; egg size did not vary across the breeding season. Nesting cycles lasted, on average, 25.8 ± 0.1 days (nest construction: 6.1 ± 0.4 days; incubation period: 11.9 ± 0.1 days; nestling period: 13.8 ± 0.1 days). At least one young fledged in 26% of nests, 62% were depredated, and 11% were abandoned. Egg survival rate was 0.95 ± 0.02, hatching success rate was 0.84 ± 0.02, and nestling survival rate was 0.81 ± 0.03. Partial nestling losses were detected in 45% of the nests, of which 52% were because of brood reduction. Each breeding pair had on average 4.4 ± 0.2 nesting attempts over the breeding season. Our results support the prediction that small clutch sizes are associated with extensive breeding seasons and several nesting attempts within a season. Except for the short incubation period, all other breeding features reported in this study differ from those of most north temperate birds and are consistent with the life history traits of Neotropical birds.

Female Red-Breasted Flycatchers (Ficedula Parva) mated with older males produce male-biased broods
Joanna Mitrus, Cezary Mitrus, and Robert Rutkowski

Recent avian studies suggest that offspring sex ratios can vary with environmental or parental characteristics. One example is that females may adjust brood sex ratio of fledglings in response to the sexual attractiveness of their mate and are expected to produce more sons when mated with older or more ornamented males. We determined offspring sex ratios at fledging (158 nestlings from 33 broods) in a population of migratory bird species, Red-breasted Flycatchers (Ficedula parva) that were breeding on the western edge of their geographic range, in the strictly protected part of the Białowieża Forest (north-eastern Poland). The ratio of individual broods ranged from all male to all female, but the average offspring sex ratio at the population level did not deviate significantly from the expected 50:50 sex ratio. Moreover, we found no evidence that sex ratio varied significantly with year, with the incidence of extra-pair paternity, with partial brood losses, or with brood size. However, females mated to older males (older males are also more ornamented) were significantly more likely to produce male-biased broods. Our data suggest that female Red-breasted Flycatchers manipulate sex ratio in response to their mate’s age.


Population Variation in Mobbing Ospreys (Pandion haliaetus) by American Crows (Corvus brachyrhynchos)
John M. Marzluff, Jack H. DeLap, and Kristina Haycock

American Crows (Corvus brachyrhynchos) aggressively mob a variety of natural predators and learn to recognize unique threats. Because mobbing is a costly and risky behavior, we hypothesized that crows would selectively ignore benign heterospecifics that look similar to predators, perhaps even learning to do so. Through a series of natural observations and experiments we found that American Crows were more likely to mob Red-tailed Hawks (Buteo jamaciensis) and Bald Eagles (Haliaeetus leucocephalus) than Ospreys (Pandeon haliaetus). Mobbing intensity was higher to a taxidermic mount of a Red-tailed Hawk than to a mount of an Osprey, indicating that mobbing increases with the risk posed by the predator. However, we also found that Ospreys were more likely to be mobbed in locations where they rarely occur, suggesting that crow populations that frequently encounter Ospreys habituate to this benign raptor. The extensive distribution of Ospreys and resulting co-occurrence with many mobbing species suggests our findings may have wide application.

Song Repertoire of Carolina Chickadees (Poecile carolinensis) in Southeastern Pennsylvania
Evan P. Kelemen, Karen E. Zusi, and Robert L. Curry

Songs of the Carolina Chickadee (Poecile carolinensis) vary throughout the species' geographic range. The aim of this study was to investigate quantitatively the repertoires of individual Carolina Chickadees in southeastern Pennsylvania. Previous qualitative work in the same region identified two song types produced with different degrees of consistency. We recorded locally breeding males during 2 years to assess song types at the population level and to characterize repertoires of individuals. Most males included the same two common song types (A and B) in their repertoires; cluster analysis also identified a third song type (B′) resulting from deletion of an initial note. The amount of variation within the song types differed, with the more stereotyped A song produced more frequently (averaging 79% of songs by individual males) than the more variable B (21%) and B′ (<1%) song types. Differences in the degree of song fidelity and repertoire composition may reflect variation in function between song types, but this hypothesis remains to be tested.

Probable Interspecific Song Learning in a Florida Grasshopper Sparrow (Ammodramus savannarum floridanus)
Erin L. Hewett Ragheb, Cody Mezebish, and Bernard Lohr

We report a case of probable interspecific song learning in a male Florida Grasshopper Sparrow (Ammodramus savannarum floridanus), a critically endangered grassland bird. This individual was observed to sing a distinctive song where the second phrase of the song accurately resembled a typical song of a Bachman’s Sparrow (Peucaea aestivalis), and the introductory phrase was intermediate between the songs of Bachman’s and Grasshopper sparrows. The exact mechanism of development of this unusual song is unknown, but scarcity of species-typical tutors as a result of rapid population decline may have resulted in interspecific song development. The atypical individual exhibited a strong response to recordings of conspecific song and successfully defended a territory in high-quality habitat but nevertheless appeared to be unpaired. Improper song learning may inhibit mate attraction and qualify as an Allee effect contributing to the extirpation of small populations.

Observation of Sandhill Cranes’ (Grus canadensis) Flight Behavior in Heavy Fog
Eileen M. Kirsch, Michael J. Wellik, Manuel Suarez, Robert H. Diehl, Jim Lutes, Wendy Woyczik, Jon Krapfl, and Richard Sojda

The behaviors of birds flying in low visibility conditions remain poorly understood. We had the opportunity to monitor Sandhill Cranes (Grus canadensis) flying in heavy fog with very low visibility during a comprehensive landscape use study of refuging cranes in the Horicon Marsh in southeastern Wisconsin. As part of the study, we recorded flight patterns of cranes with a portable marine radar at various locations and times of day, and visually counted cranes as they departed the roost in the morning. We compared flight patterns during a fog event with those recorded during clear conditions. In good visibility, cranes usually departed the night roost shortly after sunrise and flew in relatively straight paths toward foraging areas. In fog, cranes departed the roost later in the day, did not venture far from the roost, engaged in significantly more circling flight, and returned to the roost site rather than proceeding to foraging areas. We also noted that compared to mornings with good visibility, cranes flying in fog called more frequently than usual. The only time in this 2-year study that observers heard young of the year calling was during the fog event. The observed behavior of cranes circling and lingering in an area while flying in poor visibility conditions suggests that such situations may increase chances of colliding with natural or anthropogenic obstacles in the vicinity.

Incidence of Cartwheeling Flights in Raptors of South-Central Chile 
Victor Raimilla, Tomás Rivas-Fuenzalida, Alejandro Kusch, José Díaz, Jorge Toledo, Álvaro García, and Jaime E. Jiménez

Cartwheeling flight is a behavior that involves aerial locking of talons by raptors followed by a descending mutual rotation around a central axis, like a cartwheel. We provide information on 32 recorded cartwheeling events from south-central Chile involving 12 raptor species; 26 were by dyads of the same species, of which 61.5% were associated with aggressive events. Only one case was considered a courtship behavior and two as play. Milvago chimango was the most frequently involved in intraspecific cartwheeling (38.5%), whereas Geranoaetus polyosoma had the highest frequency of allospecific encounters (67%). This is the first account on the occurrence of cartwheeling flights in South American raptors, and we suspect that this behavior is more prevalent than has been reported previously.

On a Tightrope: Use of Open Sky Urban Telephone Wires by Azure-crowned Hummingbirds (Amazilia cyanocephala) for Nesting
Juan F. Escobar-Ibáñez and Ian MacGregor-Fors

Birds are considered excellent bioindicators in urban areas. Some of the ecological processes behind bird ecological patterns in urban areas have been related to birds’ capacities to shift their behaviors. In this brief communication, we report a nest of Azure-crowned Hummingbird (Amazilia cyanocephala) built on a metallic structure that connects telephone wires, surrounded by other electricity and cable wires. After visiting the nest for 19 days, we did not have any evidence of predation, and because of the size and behavior of the chicks during the last two visits, we assume that the nest was successful. Previous studies have suggested that urban systems lay open to colonization by species that can reach them, use their resources, and survive their hazards. We recorded a nest of Azure-crowned Hummingbirds that was built on an open sky telephone. Our observation was a notable example of the degree of venture that some individual birds can exhibit in response to urbanization, suggesting a certain degree of ecological plasticity. Thus, future detailed studies are needed to untangle the advantages and disadvantages of nesting on open sky urban wires, to assess if it is profitable to nest on such structures.

A Radio-telemetry Study of Home Range and Habitat Use of the Endangered Yellow-billed Cotinga (Carpodectes antoniae) in Costa Rica
Karen M. Leavelle, Luke L. Powell, George V. N. Powell, and Adrian Forsyth

The Yellow-billed Cotinga (Carpodectes antoniae) is one of Central America’s rarest and most endangered species. A regional endemic to Panama and Costa Rica, between 250 and 999 individuals appear to now survive mainly within Pacific coastal mangroves and adjacent lowland forest within the Térraba-Sierpe National Wetlands and the Osa Peninsula of Costa Rica, an Alliance for Zero Extinction Site. We used radio telemetry to determine seasonal movements and habitat use and requirements of three Yellow-billed Cotingas at the Rincón River and mangrove estuary on the Osa Peninsula. During the breeding months from approximately December to June, radio-tagged cotingas used mangroves primarily for courtship display, insect feeding, protection from inclement weather, and night roosts. They used lowland forest for feeding on fruit and insects and for infrequent courtship display. Birds fed on fruits from 23 lowland forest tree species throughout the year. Although the female ranged farther than the males during the non-breeding season, no bird showed evidence of migratory behavior. They did not wander from the Rincón mangroves during the non-breeding months from July to November, and they roosted in the same mangrove plot each night. The juxtaposition of mangroves and lowland forest rich in fruit trees may be critical to the survival of the species.

Brood Habitat Selection of Chinese Grouse (Tetrastes sewerzowi) at Lianhuashan, Gansu, China
Zhao Jin-Ming, Fang Yun, Lou Ying-Qiang, and Sun Yue-Hua

We studied habitat selection in Chinese Grouse (Tetrastes sewerzowi) hens with dependent broods at Lianhuashan, Gansu, China in 2010–2012. We divided the dependent brood period into four stages (weeks 1–2, 3–4, 5–8, and beyond 8 weeks post hatching) and compared used with available habitat, and found that hens with broods chose sites with significantly less canopy cover (0.28 ± 0.01 vs 0.49 ± 0.02), greater willow cover (0.31 ± 0.02 vs 0.14 ± 0.01), and greater herb height (21.36 ± 1.05 vs 14.43 ± 0.59). Broods used a variety of vegetation types at different stages of chick development. They used more early successional deciduous forests and shrubs during stages 2 and 3 (weeks 3–8, Kruskal-Wallis Test: χ2  =  13.918, df  =  3, P  =  0.003). Sites with more invertebrates were used in Stage 1 compared to available sites (54.5 ± 7.2 vs 36.4 ± 4.4), but not in Stage 2. Compared to sites used during stage 4, chicks in stage 2–3 used sites of earlier successional stages, greater herbaceous vegetation height, and closer proximity to forest edges, whereas sites utilized during stage 1–3 showed visits in lower willow cover.

Nest, Eggs, and Nestlings of the Atlantic Forest Endemic Star-throated Antwren (Rhopias gularis)
Daniel F. Perrella, Carlos H. Biagolini-Júnior, Lais Ribeiro-Silva, Paulo V. Q. Zima, Galetti, Pedro M. Jr, and Mercival R. Francisco

Here, we describe nests, eggs, and nestlings of the monotypic Star-throated Antwren, Rhopias gularis (formerly Myrmotherula gularis), found at Carlos Botelho State Park, in Atlantic Forest in the state of São Paulo, Brazil. Nests were pensile cups of dark rootlets and black fungal hyphae, found near forest streams, 34–70 cm high, over ground or water. A leaf appeared to form a roof over two nests. Clutch size was always two eggs, white with reddish and dark brown spots and blotches. Hatchlings were naked with pinkish skin. Nest architecture, eggs, and nestlings were similar to other Myrmotherula and Epinecrophylla, suggesting that nesting characteristics may not be informative to reconstruct recent DNA-based phylogenies that resolved the monotypic genus of this Brazilian Atlantic Forest endemic species.

Cooperative Breeding at a Nest of Slaty-backed Nightingale-Thrushes (Catharus fuscater)
Harold F. Greeney, Andrzej Dyrcz, Romuald Mikusek, and Jeff Port

Our observations on the reproductive habits of the Slaty-backed Nightingale-Thrush (Catharus fuscater) were made at a single nest between 2–12 November 2009 at an elevation of 2,050 m, in the vicinity of the Yanyacu Biological Station and Center of Creative Studies (00o 36′ S, 77o 53′ W), 5 km west of Cosanga (Napo Province, northeastern Ecuador). During the first 3 days following hatching, the only adult which provisioned nestlings was a color-banded female. Beginning with day 4, however, we observed five other individuals bringing food to the nest, including three color-banded males, one unmarked male, and one unmarked individual presumed to be female. The last two birds and one of the banded males were sexed using morphological differences, the remaining banded individuals were sexed molecularly. Most (72%) of provisioning visits to 4–9 day old nestlings were made by the color-banded female which also incubated the eggs. Our observations suggest the existence of a potentially complex cooperative breeding system in Slaty-backed Nightingale-Thrush.

First Nesting Records in Southwestern Louisiana for American Oystercatchers (Haematopus palliatus) and Reddish Egrets (Egretta rufescens), with Implications for Dredge Spoil Island Restoration 
Will Selman and Bruce E. Davis

American Oystercatchers (Haematopus palliatus) and Reddish Egrets (Egretta rufescens) are coastal species of conservation concern known to nest along most of the Gulf of Mexico’s coastline. However, there is a distributional gap in breeding records for both species between southeastern Louisiana and eastern Texas. Herein, we report on the first breeding records for each species from southwestern Louisiana at Rabbit Island (Cameron Parish, Louisiana), a small, marsh island in Calcasieu Lake. Suitable nesting habitat for American Oystercatchers (1 nesting pair) was present on the island via shell rake and for Reddish Egrets (6–12 pairs, min) in clumps of Juncus roemerianus; this is the first report of Reddish Egrets utilizing this plant species for nesting. A large scale island restoration project is slated for Rabbit Island and therefore, we provide restoration recommendations for conservation planners to improve habitat suitability for multiple bird guilds at this and other potential dredge spoil island projects.

Observations on Fecal Sac Consumption and Near-ground Foraging Behavior in the Olive-sided Flycatcher (Contopus cooperi) 
Julie C. Hagelin, Shannon Busby, April Harding-Scurr, and Aleya R. Brinkman

We present details on parental care and foraging behavior of Olive-sided Flycatchers (Contopus cooperi) in central Alaska. We document the first evidence of fecal sac consumption in this species. Both sexes exhibited this behavior while tending chicks less than one week old. Adults with older nestlings (1.5–2 weeks) removed fecal sacs only. The general pattern of reduced fecal sac consumption with chick age is consistent with other passerines and may supplement parental nutrition. Near-ground foraging behavior in C. cooperi is rarely reported, as birds typically sally for aerial insects near or above the canopy. Two breeding females fed multiple times from 1–3 m perches, hovering over, flying directly above or disappearing into low vegetation (<0.5 m) for up to 15 secs. Low stumps and saplings in a wood cutting area and in undisturbed forest provided access to patches of flowering vegetation that appeared to concentrate pollinator prey during cool or inclement weather. Given the conservation concerns for this species, its low productivity, dietary specialization, and hypothesized early-season reliance on insect prey, flowering vegetation presents a testable visual stimulus that may govern settlement behavior of breeding adults.

Common Ravens (Corvus corax) Prey on Rhinoceros Auklet (Cerorhinca monocerata) Eggs, Chicks, and Possibly Adults
James L. Hayward, Gordon J. Atkins, Ashley A. Reichert, and Shandelle M. Henson

We observed Common Ravens (Corvus corax) on Protection Island, Washington that used their bills to dig into the nesting burrows of Rhinoceros Auklets (Cerorhinca monocerata) and prey on auklet eggs. In addition, we observed a raven fly away from a burrow with an auklet chick, a raven attack and unsuccessfully attempt to capture an adult auklet, and a raven fly with and feed on a freshly killed adult auklet. Although Common Ravens have been reported to prey on Rhinoceros Auklets’ eggs, to our knowledge this is the first report of a raven preying on a chick and the first report of an attempt by a raven to capture an adult auklet.

A Modified Leg-noose Trap for Crab-plovers (Dromas ardeola) at Burrow Nests
Giorgio Chiozzi, Giuseppe De Marchi, and Mauro Fasola

Being trapped is a potentially stressful experience, especially for breeding birds, so capture should be limited to target individuals and be as least harmful as possible. We describe here a modified leg-noose trap that we developed for the burrow nesting Crab-plover (Dromas ardeola). Similar to other commonly used devices, it consists of monofilament fishing line nooses secured to a heavy metal base. We modified this traditional device by positioning the nooses perpendicular to the bird movement and by adding shock-absorbing elastic bands. This last addition proved effective in protecting the captured bird's legs from superficial wounds and abrasions; it did not affect capture success relative to a version of the same trap lacking these improvements. Such improvements could be applied to similar noose traps employed for other birds in order to reduce discomfort and avoid injury.

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