Why vocal learning has evolved in songbirds, parrots, and hummingbirds but not in other avian groups remains an unanswered question. The difficulty in providing an answer stems not only from the challenge of reconstructing the conditions that favored vocal learning among ancestors of these groups but also from our incomplete knowledge of extant birds. Here we provide multiple lines of evidence for a previously undocumented, evolutionarily independent origin of vocal learning among the suboscine passerines. Working with bellbirds (Procnias spp.), we show that (1) a captive-reared Bare-throated Bellbird (P. nudicollis) deprived of conspecific song not only developed abnormal conspecific songs but also learned the calls of a Chopi Blackbird (Gnorimopsar chopi) near which it was housed; (2) songs of Three-wattled Bellbirds (P. tricarunculata) occur in three geographically distinct dialects (from north to south: Nicaragua, Monteverde, and Talamanca); (3) Three-wattled Bellbirds at Monteverde, Costa Rica, are often bilingual, having learned the complete song repertoire of both the Monteverde and Talamanca dialects; (4) immature bellbirds have an extended period of song development, lasting the 6 years in which they are in subadult plumage; and (5) adult male Three-wattled Bellbirds continually relearn their songs, visiting each others' song perches and adjusting their songs to track population-wide changes. Perhaps female preferences and strong sexual selection have favored vocal learning among bellbirds, and additional surveys for vocal learning among other lekking cotingas and other suboscines may reveal patterns that help determine the conditions that promote the evolution of vocal learning.

Although there is a large body of literature dealing with the nature of geographic variation in the songs of birds, few studies have examined such variation across the entire range of species of suboscine birds. We measured time and frequency characteristics of songs of Alder Flycatchers (Empidonax alnorum) from six regions spanning almost the entire range of the species, from Alaska to Maine. Both univariate and multivariate analyses demonstrated significant differences in song characteristics among regions, and discriminant function analysis classified 69% of songs to the correct region. We found no relationship between geographic separation and magnitude of difference in songs among regions—songs of birds from some widely-separated regions were more similar than they were to songs of birds from neighboring regions. We argue that these regional differences have a genetic basis, but the pattern of variation does not appear to be consistent with a simple “isolation by distance” model. The variation may reflect differing adaptation to optimize acoustic transmission in varying habitats across the range. However, more detailed studies, including examination of genetic variation among populations, are required to test such suggestions rigorously.

We studied patterns of geographic variation in the fine structural characteristics of the songs of five recognized subspecies of Common Bush Tanagers (Chlorospingus ophthalmicus) in Mesoamerica to examine whether songs vary with geography. Multivariate analyses (PCA and DFA), based on 11 fine structural characteristics of the songs provided similar results indicating that both albifrons and regionalis had unique songs significantly different from the rest of the subspecies. Conversely, ophthalmicus, dwighti, and postocularis had similar song characteristics, regardless of restricted gene flow and substantial morphological variation reported in previous studies. Our findings suggest there is a possible relationship between the length of isolation and variation in songs of albifrons and regionalis, whereas the lack of divergence in songs of ophthalmicus, dwighti, and postocularis suggests some of these forms have not diverged vocally, and vocal traits may be evolutionary conserved.

We collected behavioral observations and recordings of adult Eurasian Stone-curlews (Burhinus oedicnemus) in central and northern Italy, and of chicks in northern Italy. Eurasian Stone-curlews are highly vocal during spring and summer, and vocalize routinely, but less frequently, during fall and winter nights. Adult Eurasian Stone-curlews have a complex and relatively wide vocal repertoire composed of at least 11 different call types and some subtypes. Two of these calls (Kurlee and Gallop) are the most used and important; the Kurlee call is uttered year-round, while Gallop is uttered usually during the breeding season with a peak in spring. Adult vocalizations are structurally diverse; call syllable duration spans from < 0.1 to > 1.1 sec and average center frequency is between 2,190 to 3,037 Hz. The highest frequency is associated with a high intensity alarm call; some adult vocalizations can be compared to the loud rhythmically repeated calls which often occur in several species of Charadrii and Scolopaci. Five call types are used in well-defined circumstances suggesting specialized functions; the remaining calls are used mostly in combination with other call types, particularly Kurlee and Gallop calls. There are preferred and typical call combinations, which cannot be explained as random choices. We identified two main call types for chicks, which are completely different from adult calls and are developed before hatching. Juveniles up to 70 days of age utter these calls without major changes. We discuss preliminary data on vocal ontogenesis, as well as correspondences and differences between our findings and the existing literature on the adult repertoire.

We investigated the impacts of an unpaved road on the distribution, reproduction, and stress physiology of Mountain White-crowned Sparrows (Zonotrichia leucophrys oriantha) in a high-elevation subalpine ecosystem. We found and monitored 152 sparrow nests over 3 years and captured 123 sparrows over 2 years for standardized stress series experiments. Distance of a nest to the road was associated with reproductive success, and low success near the road was primarily because of high rates of nest desertion. The probability of a nest succeeding rose with increasing distance from road up to 40 m, but nests beyond 40 m experienced lower nest success, possibly because of increased predation. Nests at intermediate distance were approximately twice as likely to succeed (70% survival rate) as those near (36% survival) or far (37% survival) from the road. Stress response of male sparrows subjected to a standardized field stress protocol was elevated within 20 m of the road (38.34 ± 5.76 ng/ml) compared to those at greater distances (23.89 ± 2.01 ng/ml). Our study is the first to document the association between the distance to a road and blood corticosterone levels in any bird species. The results present strong evidence of impacts of a road on nest success of a migratory songbird. This relatively low-traffic, low-speed road clearly presents problems, even for a bird species not thought to be sensitive to disturbance.

We conducted 3,050 point counts from 2005–2009 (May–Jul) in 82 wetlands in three Canadian provinces (Ontario, Québec, and Manitoba) to quantify colonization and extinction dynamics of Least Bittern (Ixobrychus exilis) populations to detect geographic variations across provinces and to analyze effects of weather conditions, date, and survey methodology that may affect detection probability of Least Bitterns. Least Bitterns were detected at 773 (25%) of the 3,050 point counts with birds detected in 25, 26, and 28% of all point counts in Ontario, Québec, and Manitoba, respectively. Occupancy probability in the first year of the study was lower in Québec sites (0.26) compared to Manitoba sites (0.53). However, Québec sites had higher probabilities of colonization (0.67) than Ontario (0.32) and Manitoba (0.27). Probabilities of extinction did not differ across provinces but varied across years. Detection probability did not vary with weather variables (cloud cover, wind speed, air temperature – linear or quadratic effect) but decreased from mid-May (0.19) to mid-July (0.09). Detection probability was lower (0.13) for the first passive listening period than the call-broadcast period (0.28) and the second passive listening period (0.33). Observed differences in extinction and colonization probability between provinces and years show that occupancy dynamics vary both temporally and geographically, stressing the need to continue long-term monitoring of Least Bittern populations across the breeding range to detect geographic variation and changes in occupancy. We recommend Least Bittern surveys begin in mid-May at higher latitudes and use a second passive listening period following the call-broadcast period to increase detection of the species.

Nearctic-neotropical passerines may spend up to one-third of the year in migration. Stopover sites have a critical role in providing migrant passerines with areas to rest and replenish fat stores. We characterized the stopover ecology of the Tennessee Warbler (Oreothlypis peregrina) at an inland site in Vicksburg, Michigan, using data from 4,607 warblers captured between 1990 and 2007. The recapture rate ranged from 1.6 to 12.1% annually and recaptured migrants averaged small but significant mass gains. Estimates of mass change using regression of mass on time of capture also suggested mass increases at this site. Recapture rate and mass gain estimated by regression varied significantly across the 18 years of study, although stopover length and mass change among recaptured individuals did not. Adult (after hatching year, AHY) warblers in active flight feather molt had an average lower mass and were four times more likely to be recaptured than non-molting adults. Over 95% of birds captured were hatching year (HY). The average condition and mass gains estimated by regression of HY warblers were lower than that of AHYs, but recapture rate, stopover length, and mass gains by recaptured individuals did not differ between the two age groups. The high number of captures and mass gains demonstrate the value of this site for fall migrant Tennessee Warblers. The annual differences in recapture rate and mass gains reported in this study suggest that several years of data may be needed to develop an accurate assessment of the typical use of a stopover site by migrants.

We quantified changes in long-term Snowy Plover (Charadrius nivosus) survey counts and return rates, estimated current sex and age-specific apparent survival and encounter rates, and calculated recruitment thresholds needed to maintain a stable population in the Southern High Plains of Texas. Mean survey counts of adult Snowy Plovers decreased by 78% at one saline lake (from 80 adults/survey to 18 adults/survey) from 1999–2000 to 2008–2010 but remained consistent at an alternate lake (from 45 adults/survey to 41 adults/survey). Adult and juvenile return rates have similarly declined within this time frame by 25 and 62%, respectively. Long-term declines in return rates may be the result of increased mortality from declining habitat conditions either within or outside the breeding season. Current estimates of adult (65%) and juvenile (12%) apparent survival are lower than most other estimates for Snowy Plovers throughout their range. Current estimates of adult and juvenile apparent survival and return rates indicate 5.8–10.0 hatchlings per adult per year are needed to maintain the current population without immigration, a 3–5 fold increase in the past 10 years.

Baltimore Orioles (Icterus galbula) of unusual redness over large sections of their plumages were recently discovered in southeastern Canada. Reddish feathers from six of nine specimens sampled at the McGill Bird Observatory in Ste-Anne-de-Bellevue, Montreal, Quebec in fall 2006 contained rhodoxanthin, a keto-carotenoid of deep red hue usually found in plants. Rhodoxanthin comprised ∼5% of carotenoids in many oriole feathers, and up to 18% in the reddest one. Redness in oriole feathers with rhodoxanthin correlated with amounts of that pigment, rather than with amounts of red 4-keto-carotenoids like canthaxanthin normally present in orange oriole feathers. Redness in feathers with rhodoxanthin also tended to be greatest in feathers with the least amounts of carotenoids. The anomalous rhodoxanthin altered the normal relationship between redness and 4-keto-carotenoid concentration, and total feather carotenoid concentration in Baltimore Orioles. We believe rhodoxanthin and the associated aberrant reddish tones result from consumption of berries of exotic bush honeysuckles (Lonicera spp.), now widely propagated in eastern North America and the Midwestern United States. We confirm the presence of rhodoxanthin in the berries of Tatarian honeysuckle (L. tatarica). Rhodoxanthin produces a shoulder at ∼520 nm of the reflectance spectrum of feathers in which it occurs.

We evaluated whether fruit selection by autumn-migrating birds at an important stopover site in southern New England was related to water-soluble antioxidant content of fruits. We measured total anthocyanins, total phenolics, and total antioxidant capacity in fruits from common native and non-native plant species and related this to estimates of fruit selection by free-living birds. Birds selected certain fruits over others, with arrowwood (Viburnum recognitum, V. dentatum) consumed at the highest rate, followed by Virginia creeper (Parthenocissus quinquefolia) with much lower consumption of other fruits (e.g., oriental bittersweet [Celastrus orbiculatus], multiflora rose [Rosa multiflora], winterberry [Ilex verticillata]). Antioxidant concentrations primarily differed by shrub species and less so between sites. Arrowwood spp. had the highest total antioxidants, followed by Virginia creeper, northern bayberry (Myrica pennsylvanica), chokeberry spp. (Aronia prunifolia, A. melanocarpa), multiflora rose, winterberry, and oriental bittersweet. These results are consistent with the hypothesis that free-living birds select fruits based, in part, on antioxidant content. We suggest birds may actively select polyphenol/anthocyanin-rich fruits during autumn migration to protect themselves against the potentially damaging effects of oxidative stress caused by long-distance fasting flight.

The effects of post-laying egg spottiness on nestling condition and parental provisioning were investigated in a nest box-breeding population of European Starlings (Sturnus vulgaris). Our objectives were to ascertain whether egg spottiness was associated with the nest ectoparasite Carnus hemapterus, and to examine potential relationships between egg spottiness, presence of C. hemapterus, nestling condition, and parental provisioning effort in European Starlings. Spotted-egg clutches were present over all 3 years in our population, but the spots did not reflect C. hemapterus abundance. Nestlings from spotted-egg clutches did not have more C. hemapterus than those from unspotted-egg clutches. However, nestlings from spotted clutches were in better condition than those from unspotted clutches. Nestling condition was not associated with C. hemapterus abundance. Adult male and female provisioning rates to the offspring did not differ between spotted and unspotted clutches. Similarly, the proportion of provisioning visits by males did not differ significantly between spotted and unspotted clutches, indicating that parents in our population of European Starlings do not use egg spots as a cue to altering their provisioning effort. Further research is required to fully understand the cause and consequences of egg spots in European Starlings.

We studied the Lesser Elaenia (Elaenia chiriquensis) to understand temporal patterns of occurrence and breeding of an intratropical migrant in a highly seasonal savanna (Cerrado). We tested the hypotheses that: (1) occurrence of the Lesser Elaenia in breeding areas is long, as expected for a migrant breeding in the Neotropics, and (2) the breeding period is also lengthy, as the breeding window increases in tropical latitudes. We recorded the abundance of individuals (n  =  5,603 records) and nests (n  =  502) during three breeding seasons (2005–2007). The Lesser Elaenia occurred in the study area during a 4.5-month period (between Aug and Dec  =  132 days), but was abundant during a shorter period (105 days). An interval of 2.5 months (77 days) occurred between the first and last egg-laying dates, concentrated in a shorter interval (63 days). The occurrence period of the Lesser Elaenia in the Cerrado was one of the shortest recorded for a neotropical migratory flycatcher and was most similar to other congeneric species that breed at higher latitudes. The breeding period in this tropical seasonal environment may be intermediary between the humid tropics and the south temperate region.

We investigated the amount of time Black-tailed Gulls (Larus crassirostris) incubated and its effects on hatching interval within two-egg clutches. Incubation patterns were classified into three categories (rising, steady, or pulsed) related to daily change of incubation rate until clutch completion. Hatching intervals (mean ± SD, 0.95 ± 0.76 days) were significantly shorter than laying intervals (2.56 ± 0.75 days). There was a significant positive relationship between incubation rate on the day when the first egg was laid (day 1) and hatching interval (Spearman's r_s  =  0.677, P  =  0.016). The incubation rate on day 1 also increased (Spearman's r_s  =  0.521, P  =  0.039) as the breeding season progressed, and hatching interval expanded (Kruskal-Wallis test: χ²₂  =  8.3, P  =  0.016, range  =  0–2 day). Thus, the amount of time gulls spent incubating on day 1 was important in affecting hatching intervals and suggested that parents partially controlled hatching intervals with seasonal change by timing of the onset of incubation in this species.

Whooping Cranes (Grus americana) are a long-lived, monogamous avian species, yet little documentation of copulatory behavior and timing in relation to egg-laying has occurred in wild populations. We monitored 10 crane pairs in Florida before and during the 2010 breeding season to document copulation timing and pre- and post-copulatory behavior. Monitoring began 111 days before incubation initiation for the first nest of the season. Pairs were observed for 124.62 hrs (  =  76.30 min, range  =  14–375 min) during 98 observation periods; 17 observation periods occurred on days with precipitation. Three copulations were observed, two by one established pair and another by unpaired individuals. The copulations by the established pair occurred 9 and 18 days before incubation began. The third was an extra-pair copulation, which occurred between a paired female and a lone male, the first documented for the species. No copulations were observed on days with precipitation. We examined flock monitoring accounts from 1999 through 2009 in this non-migratory population; 21 observations of copulations revealed Whooping Cranes copulated up to 62 days before incubation began and between 0510–1345 hrs EST. Our data suggest copulation occurs between early morning and early afternoon and does not appear to be associated with precipitation.

Feral herbivores can affect birds on islands indirectly, by altering habitat structure via impacts on vegetation. I censused birds in an open shrub/grassland habitat on Santa Cruz Island, California, in 1980 and again in 2008, 24 years after feral sheep were removed, in order to assess avian responses to vegetation changes resulting from sheep removal. Vegetation change was characterized by an increased density of both overstory and low-growing shrubs, along with denser herbaceous vegetation, and these characteristics were associated with substantial changes in bird abundance. Species that prefer dense shrubs, such as Spotted Towhees (Pipilo maculatus) and Orange-crowned Warblers (Oreothlypis celata), increased in abundance, whereas species such as House Finches (Carpodacus mexicanus) and Mourning Doves (Zenaida macroura) that prefer open, disturbed areas decreased. Rufous-crowned Sparrows (Aimophila ruficeps) and Island Scrub-Jays (Aphelocoma insularis), both insular endemic taxa, showed a mixed response and perhaps prefer wooded habitats in which low-growing vegetation is not exceptionally dense.

The Caucasian Grouse (Lyrurus mlokosiewiczi) is of conservation concern because it has been declining at least since the 1980s and has disappeared from parts of its range. We quantified landscape composition and configuration around Caucasian Grouse lek sites and random points within the Arasbaran Region in northeastern Azerbaijan, Iran at multiple scales (200-, 500-, and 1,000-m radii circles). We developed averaged logistic regression models based on Akaike Information Criterion weights for each scale. Habitat suitability models indicated good discrimination based on the receiver-operating characteristic (ROC) criteria (three averaged-models had ROC values >0.8), indicating landscape pattern can explain distribution of leks reasonably well. Unconditional, model-averaged estimates and 95% confidence intervals for beta estimates of variables included within buffer-width models suggest leks in the 200-m buffer width are in areas with lower standard deviation in patch area. Lek sites in the 500-m buffer-width models were predicted to be absent in landscapes where patches are more insular and have higher edge contrast. Lek sites were more likely to be present in landscapes having larger patches that were more irregular in shape and in habitats containing more patch types and greater proportion of forest and range cover types. The model-averaged estimates for the explanatory variables within the 1,000-m buffer width indicated lek sites were more likely to be present in landscapes that have high spatial heterogeneity as patches are more insular and contain the most forest and range cover types.

We studied the breeding biology of the Straight-billed Woodcreeper (Dendroplex picus) (Dendrocolaptinae) from eight nests in Hato Masaguaral, Venezuela and reviewed current literature for all woodcreeper species. Straight-billed Woodcreepers nested in PVC nest-boxes (n  =  6) and in wooden fence posts (n  =  2). Mean ± SE clutch size was 2.50 ± 0.19 eggs (n  =  8) and egg mass was 5.41 ± 0.12 g (n  =  17). Egg mass and clutch mass represented 12.4% and 31% of adult mass, respectively. Both males and females incubated, but average incubation nest attentiveness (percent of time on the nest) was only 63.2 ± 8.2% (n  =  8). The relatively low nest attentiveness was associated with an incubation period of 17 days (n  =  1). The nestling period was 17–18 days (n  =  2), and both parents provisioned the young. Nestling growth rate constants (K) for mass, tarsus, and wing chord were 0.45 ± 0.04, 0.34 ± 0.03, and 0.27 ± 0.02, respectively. Three of eight nests were successful and five were lost to predation. Comparisons with other woodcreepers for many traits are difficult because of limited information. The available information indicates female-only and biparental incubation exists within the Dendrocolaptinae. Our observations of the Straight-billed Woodcreeper add Dendroplex to the genera with biparental incubation.

The Laysan Finch (Telespiza cantans) is an endangered Hawaiian honeycreeper that occurs on only a few small islands in the northwestern Hawaiian Island Archipelago. Twenty-two years of recent population estimates (1991–2012) from Laysan Island were analyzed to ascertain the current status of this endangered species; the entire 44 years of census data available were then used to identify long-term population trends. Laysan Finch population estimates have exhibited extreme fluctuations that can be attributed at least in part to spring rainfall patterns. The average population size has remained at ∼10,000 individuals. The Poisson regression analysis conducted for the last 22 years indicates a slightly deceasing annual population trend. However, when all 44 years of data were included in a comprehensive trend analysis, a stable population trend was documented. These results highlight the importance of long-term data sets when monitoring small closed populations - a situation commonly encountered with endangered species. Inherent resilience has allowed the finch population to rebound from declines and fluctuate around Laysan Island's carrying capacity, but the future is uncertain as climate change is expected to impact its low island habitats.

We studied exploitation of reedbeds by two specialist passerines, Reed Parrotbill (Paradoxornis heudei, listed as Near Threatened by the IUCN) and Oriental Reed Warbler (Acrocephalus orientalis), nesting in a tidal reedbed in the Changjiang River Estuary. Reed Parrotbills have significantly shorter, wider, and deeper bills than Oriental Reed Warblers. We distinguished >12 nest material categories in four groups (Phragmites, Zizania, artificial, and other) in nests of the two species. Reed Parrotbills used significantly fewer nest material categories, and had lower nest material diversity and a narrower nest material niche than Oriental Reed Warblers. More than 89% of the nest mass of Reed Parrotbills was Phragmites and was obtained from within the nesting habitat. More than 71% of the nest mass of Oriental Reed Warblers was Zizania from outside the nesting habitat. Most Phragmites material used by Reed Parrotbills was living tissue from reed leaf sheathes and stems. The large bill of the Reed Parrotbill facilitates exploitation of tissues from living reed shoots for nest materials, while the relatively long and slender bill of the Oriental Reed Warbler constrains it to use living reed shoots and exploit nest material from outside of nesting habitats. This is similar to their exploitation of food resources in reedbeds: Reed Parrotbills extract concealed insects within reed shoots while Oriental Reed Warblers glean exposed arthropods on a variety of plants. We confirm that food resource exploitation by Reed Parrotbills and Oriental Reed Warblers demonstrates a relationship between bill morphology and feeding as well as nest building.

We compared House Wren (Troglodytes aedon) nests in nest boxes with either small (28 mm) or large (38 mm) entrance holes. Spring clutch size did not differ between wrens using boxes with large and small holes. Nests in boxes with large holes had a significantly taller ‘berm’ of sticks between the box entrance and the nest cup than did nests in boxes with small holes. This was true even when the same wren pairs were given boxes with different-size holes for spring and summer nests. We compared the difficulty of touching the eggs when we removed the frontplate of the nest box as an alternative measure of nest vulnerability to predators and brood parasites. There was a significant association between hole size and accessibility: boxes without the protection of a small entrance hole were far more likely to be categorized as ‘inaccessible.’ We found a similar relationship between berm height and nest architecture: nests with tall berms were generally less accessible than were nests with shorter berms. Contrary to earlier claims, House Wrens alter nest architecture to compensate for vulnerability of cavities with large entrance holes.

We studied nestling provisioning and male song behavior associated with provisioning by Carolina Wrens (Thryothorus ludovicianus) throughout the nestling period. Overall, males and females (n  =  14 pairs) provisioned at similar rates throughout four nestling stages although males tended to provision more at the earliest nest stage (1–3 days). Males and females increased their rate of provisioning progressively over the nestling period. Parents brought one food item at a time to the nest and load sizes were similar between males and females, and between early and late nest stages. Males sang 34% of the time on arrival at nests to provision and 49% on leaving nests after provisioning. There was no relationship between male song and age of the nestlings. Males sang more after provisioning nestlings when females were not present (55%) than when females were present (33%) at the nest. The function of male song during provisioning may be to communicate the male's location to the female and to indicate he has recently provisioned the nestlings but this requires further study.

We monitored territory density, nest density, date of nest initiation, nest height, and associated vegetation characteristics of Marsh Wrens (Cistothorus palustris) in two marshes managed with herbicide in late summer 2009 to control Phragmites. Average territory density declined fourfold from 2.39 to 0.54 territories/ha (one-tailed t-test, P  =  0.004), and average active nest density declined tenfold from 1.43 to 0.12 nests/ha (one-tailed t-test, P  =  0.055) between 2009 and 2010. The mean date of nest initiation was twice as late in 2010 (21 Jul) as in 2009 (15 Jun), one-tailed t-test, P  =  0.009. Mean nest height was similar (one-tailed t-test, P  =  0.20) in 2009 (86.4 cm) and 2010 (79.6 cm), but the vegetation took longer to reach these heights in 2010, particularly at Old Woman Creek National Estuarine Research Reserve. These results suggest large scale aerial herbicide applications to manage Phragmites compromised productivity of Marsh Wrens in the coastal marshes studied. Caution should be used when considering broadcast, aerial applications of herbicides to treat Phragmites in habitats of marsh-dependent, declining, avian species.

We examined comparative food use and provisioning of Golden-fronted (Melanerpes aurifrons) and Ladder-backed (Picoides scalaris) woodpeckers at the Rob and Bessie Welder Wildlife Foundation Refuge, in San Patricio County, Texas. We combined video surveillance and direct observations to monitor provisioning rates and identify items delivered by adult woodpeckers to nestlings. We collected 328 hours of data at Ladder-backed Woodpecker nest cavities and 230 hours of data at Golden-fronted Woodpecker nest cavities. Ladder-backed Woodpecker nestling diets consisted of 100% animal matter, comprised of invertebrate larvae (99%) and invertebrate adults (< 1%). Diets of Golden-fronted Woodpecker nestlings were also high in animal matter (77%) with more invertebrate adults (55%) and fewer invertebrate larvae (27%), but also included vegetable matter (16%). Morisita's measure of overlap suggested a relatively low dietary overlap of 31% between nestlings of these two sympatric woodpecker species. Foraging methods used by these species may explain their low dietary overlap and facilitate their coexistence.

Neotropical migratory bird survivorship during the time they spend in wintering areas has been of major concern during the last several decades, yet still little is known about it. Evidence of behaviors that could increase the probability of individual survival, as well as increasing future reproductive success such as winter site fidelity and winter residency have gradually been documented for several migratory species. No evidence of these behaviors has been documented in urban areas. We present the results of a 9-year monitoring study in the green area of the Ethnobotanical Garden in the urban area of Oaxaca, Oaxaca, Mexico, using banding. Six of the 48 neotropical migratory species captured were selected for analysis of winter site fidelity and winter residency. The Warbling Vireo (Vireo gilvus) had the highest recapture rate (31.7%) with the highest winter fidelity (14.6%) and winter residency (24.4%). The next four species had recapture rates between 10.6–15.7%, winter fidelity between 6.0–10.4%, and winter residency between 5.1–19.1%. The Cedar Waxwing (Bombycilla cedrorum) demonstrated neither winter fidelity nor winter residency. Our results suggest urban green space areas may have an underestimated role in migratory bird conservation.

We observed a pair of Belted Kingfishers (Megaceryle alcyon) as they initiated burrow excavation in a bank along Rattlesnake Creek near Missoula, Montana in April 2010. During 180 min of observation on the first three mornings (17–19 Apr) of burrow excavation we observed the kingfishers fly rapidly at the bank from perched or hovering distances of 1–3 m and strike the bank bill-first 176 times, forming a pit in the vertical bank about body-deep after 60 hrs of work. Both sexes performed aerial ramming, at roughly the same rate. On the fourth morning we saw no ramming during 40 min of observation while excavation continued, but the site was abandoned later in the day. Aerial ramming at the start of burrow excavation appeared necessary because (1) the bank was vertical to overhanging without exposed roots, providing no opportunity for the birds to perch at the excavation site when beginning to dig, and (2) the birds seemed unable to strike the substrate with sufficient force to promote excavation while perched on the bank or hovering at the burrow entrance until several days into excavation, perhaps due to the presence of imbedded gravel and cobble in the soil. At least 13 species of kingfishers in the subfamilies Alcedininae and Daceloninae are reported to aerial ram into potential burrow sites (banks, termitaria, trees). Ours appears to be the first report of aerial ramming by the Belted Kingfisher and a member of the subfamily Cerylinae.

We present the first detailed report of an apparently leucistic Darwin's Finch, observed on Punta Cevallos, Española Island, Galápagos (01° 23.61′ S, 89° 37.11′ W). We suggest that the unusual adult phenotype is a continuation of nestling beak color, which is usually masked by melanin in adults. Tissue-specific differences in beta-carotene dioxygenase 2 enzyme activity may explain the variation in yellow pigmentation in this individual's legs and beak.

The Taiwan Yuhina (Yuhina brunneiceps) and White-eared Sibia (Heterophasia auricularis) are nectar-feeding babblers endemic to Taiwan. We describe the morphological features of the brush-tipped tongues of these species. The tongue divides into two parts and then into four parts towards the distal end for both species. The tongues of the Taiwan Yuhina and White-eared Sibia are specialized organs adapted for collection of nectar.

We studied Black-necked Cranes (Grus nigricollis), a Globally Vulnerable species and the only alpine breeding cranes in the world, to test whether and how predation vulnerability and flock size affect vigilance. Crane flocks were defined as high predation vulnerability (parents with juveniles) and low predation vulnerability (adults without juveniles). Both predation vulnerability and flock size influenced vigilance of Black-necked Cranes. High predation vulnerability flocks were significantly more vigilant than low predation vulnerability flocks at both the group scan level (t  =  2.379, df  =  66, P  =  0.02) and group scan frequency (t  =  3.208, df  =  66, P  =  0.002). Predation vulnerability and flock size affected vigilance in Black-necked Cranes (ANCOVA: group scan level, flock size: F  =  13.013, P  =  0.001, predation vulnerability: F  =  7.728, P  =  0.007); group scan frequency, flock size: F  =  13.873, P < 0.001, predation vulnerability: F  =  10.882, P  =  0.002).

Predator-prey interactions occur regularly in nature; however, predation events are difficult to observe in the canopy of tropical rain forests. We describe a successful capture of a Chestnut-mandibled Toucan (Ramphastos swainsonii) by a Collared Forest-Falcon (Micrastur semitorquatus) in Carara National Park, Costa Rica. The predator-prey interaction lasted for ∼30 min from the moment of the first wounding strike in the canopy to the killing of the toucan on the ground. During the predation process, the falcon engaged in multiple attacks from different directions at the sub-canopy level. We video recorded a total of 323.3 sec tracks during the predation event to produce a detailed description of the behavior of both species. In addition, we analyzed the structure of the call of the toucan while being attacked and compared that with a regular call of another individual recorded at a different time in the same area. The toucan produced a distress call with strong harmonics and a broad-band rattling sound as a threatening call. We comment on the possible function of the calls.

James's Flamingos (Phoenicoparrus jamesi), also known as Puna Flamingos, are distributed primarily in the Andean wetlands of southern South America during the breeding season, and dispersed through the lowland wetlands in Argentina during the non-breeding season. However, the main sites where they concentrate during the non-breeding season still remain unknown. Here, we report the first records of James's Flamingos observed in two consecutive years (two adults in Aug 2010, one adult and two subadults in Jul 2011) at Laguna Melincué, a Ramsar site in Santa Fe Province, Argentina (33° 25′ S, 61° 28′ W, 84 m asl). James's Flamingos were feeding in a mixed flock of Andean and Chilean flamingos (Phoenicoparrus andinus and Phoenicopterus chilensis, respectively). Our observations constitute the southernmost record for presence of this flamingo species at any lowland site and indicate the high dispersal ability of this species and its plasticity in occupying different wetland types during the non-breeding season.

Thripadectes, a little studied genus in Funariidae has thorough nest descriptions for five of its seven species, most consisting of one or two nests. Although the nest of Thripadectes holostictus has been described, it is based only on two nests, and there is no nest description for the subspecies, T. h. moderatus, which we report in this study. Between October and December 2011, we monitored four nests of T. h. moderatus in Manu National Park, Peru. In addition to reporting the first nest for the subspecies T. h. moderatus, we provide new information for T. holostictus, including incubation period (between 13–17 days), fledgling period (20–23 days), fresh egg weights (x ¯ ± SE  =  5.8 ± 0.1 g), nestling growth patterns, further evidence for biparental care, and new observations on nest materials.