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El 5 de octubre del 2019 se capturó un individuo de Catharus fuscescens, como parte de los muestreos mensuales del proyecto Monitoreo de las poblaciones de avifauna en el departamento de Loreto – Perú realizado por el Observatorio de Aves Loreto - LBO en la comunidad de San Rafael, distrito de Indiana, departamento de Loreto. Esta captura representa el primer registro documentado de C. fuscescens para el departamento de Loreto, confirmando la condición sugerida de migrante raro en el extremo noreste del Perú en su paso hacia el sur durante su migración hacia Sudamérica.

Veery (Catharus fuscescens) is a breeding migrant thrush that nests throughout much of the temperate forests within Canada. Habitat loss and degradation is thought to be responsible for a steady decline in Veery populations since 1970. We studied habitat characteristics of occupied Veery territories versus unoccupied adjacent areas in southern Ontario during the 2016 breeding season. Occupied territories were characterized as riparian deciduous forests dominated by ash (Fraxinus spp.), Black Cherry (Prunus serotina), and Red Maple (Acer rubrum) trees with an understorey of Balsam Fir (Abies balsamea) and ferns (order Polypodiales); the presence of fruit-producing plants such as Riverbank Grape (Vitis riparia) and Bunchberry (Cornus canadensis) also was important. [ABSTRACT FROM AUTHOR]

At the nest guild level, nest predation is a major cause of failure for many passerines. Species differ in behaviors that influence nest predation risk, presenting a challenge to nest survival analyses at the nest guild level. At our study site in southeastern New York, previous findings have suggested rodent nest predator abundance strongly drives daily nest survival of the Veery ( Catharus fuscescens), a ground or low shrub-nesting songbird. In cue playback experiments, the sympatric ground-nesting Ovenbird ( Seiurus aurocapilla) shows a greater aversion to chipmunk vocalizations than Veeries. These behavioral differences suggest these two sympatric ground-nesters may be driven by different ecological mechanisms despite similarity in their nesting niche. We examined how nest predator abundance, regional songbird abundance, and timing of nest activity during the breeding season influence nest survival in two songbirds from the same nest guild by building competitive models for determining the extrinsic drivers of daily nest survival. Ovenbird nest survival was best described by nest activity date, where nest survival decreased later in the breeding season, and was positively influenced by conspecific density. Nest survival of Veeries was strongly and negatively influenced by both nest predator abundance and regional abundance of Veeries. Thus, the strong relationship between nest predator abundance and nest survival observed in Veeries does not extend to Ovenbirds. These sympatric ground-nesting songbirds differ in how nest predators influence nest survival, therefore highlighting the importance of considering species-specific differences within nesting guilds to better understand nest survival at multiple ecological levels. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Northern South America is a geographic bottleneck that may be limiting the survival of Nearctic-Neotropic migrants. However, very little is known about the migration ecology of transcontinental migrants wintering in South America. We studied the fall migratory strategies of three species of thrush (Catharus ustulatus, C. fuscescens, and C. minimus) at 2 major migrant gateways into South America: the Darién and the Sierra Nevada de Santa Marta (SNSM) of northern Colombia. Assuming that migration route shapes the stopover strategy of birds and that our sites receive birds from 2 different routes, we predicted that (1) migrants traveling over land through Central America (Dari én) would make short and frequent stopovers followed by short flights and (2) migrants crossing the Caribbean (SNSM) would make few and long stopovers to acquire fuel for longer flights. To test these predictions, we estimated condition on arrival, stopover duration, fuel deposition rates, and potential flight ranges after stopover, using 3 yr of capture-recapture data. Each species adopted a different stopover strategy, with Swainson's Thrush arriving in South America through the Darién, making the shortest stopovers and achieving the shortest flight ranges (800 km); Gray-cheeked Thrush arriving primarily through the Darién, making short stopovers but achieving longer flight ranges (1,200 km); and Veery arriving in both the Darién and the SNSM, making the longest stopovers and achieving the longest flight ranges (1,900 km). Our results suggest that stopover strategies are shaped by both migratory route (over land vs. over water) and distance to final destination in South America. Unraveling the breeding origins and wintering destinations of individuals passing through northern Colombia would greatly improve our understanding of hemispheric migration systems and will be critical if we are to protect the most important stopover sites and habitats. [ABSTRACT FROM AUTHOR]

Reports of interspecific parental behavior are rare but widespread among avian taxa. We present the first known case of interspecific parental care by a Wood Thrush (Hylocichla mustelina) at a nest of the Veery (Catharus fuscescens), documented by video at a long-term study site in northern Delaware, USA. We provide data on nest chronology, quantify parental behavior, and describe a copulation event between the Wood Thrush and the female Veery that was captured on video. Despite incurring no obvious fitness benefit, the Wood Thrush provided significant and prolonged nestling care including more feeding attempts and sanitation maneuvers than either Veery. We propose that these observations are a consequence of the normal adaptive behavior of the recipient species. [ABSTRACT FROM AUTHOR]

This article focuses on the use of geolocators to track five Veeries for one annual cycle. It explains the method used in attaching geolocator units to 24 Veeries using a Rappole-Tipton leg-loop. The study results showed that 16 Veeries were relocated at the study site in 2010 out of the 24 that received geolocators in 2009. From only five Veeries, the study documented three different migratory routes between South and North America and three different routes from the Gulf Coast to Delaware.

Four thrush species are sympatric in the central Appalachians: Veery (Catharus fuscescens), Hermit Thrush (C. guttatus), Wood Thrush (Hylocichla mustelina), and American Robin (Turdus migratorius). The four species often nest near one another, which suggests that habitat partitioning may have developed to minimize past interspecific competition. Our objectives were to determine which specific characteristics of nesting habitat were partitioned among the species and to evaluate the relationship of these characteristics to nest survival. We monitored nests and sampled habitat variables at three spatial scales: nest substrate, nest site, and territory. A multivariate analysis of variance indicated a difference (P < 0.01) in the nest sites of all species and in each pairwise species contrast. An analysis of variance and Fisher's exact tests detected differences (P < 0.05) among species in 21 of 36 variables measured. Classification tree analysis correctly classified nests by species at a rate better than would be expected at random. Habitat partitioning among the four thrush species occurred at all three scales sampled, with the most important partitioning variables being nest height, distance-to-edge, sapling density, and elevation. Mayfield logistic regression found a positive relationship (P < 0.05) between decreasing nest height and American Robin nest survival. Overall, nest survival was similar among the four thrush species examined, and most of the variables that we measured were unrelated to survival. [ABSTRACT FROM AUTHOR]

For some species of forest-breeding birds, productivity is much higher in large forest fragments than in small forest fragments and is higher than the level needed to replace individuals within the fragment (sources). Thus large forest fragments potentially provide excess individuals to neighboring small fragments where productivity is much lower and not adequate for replacement (sinks). We used occurrence data and distances between putative sources and sinks for four species of forest birds with this pattern of demography in large and small forest fragments to predict occupancy in small fragments. For the Ovenbird ( Seiurus aurocapilla), Wood Thrush ( Hylocichla mustelina), Veery (Catharus fuscescens), and Rose-breasted Grosbeak (Pheucticus ludovicianus), distance from large woodlots was a significant predictor of occurrence in small woodlots. Distance from large woodlots did not predict occupancy of Red-eyed Vireos ( Vireo olivaceus), a species with no apparent difference in productivity in relation to fragment size. Neither vegetation features nor area of the small woodlots adequately explained patterns of occupancy for any species. These results suggest that maintenance of large, productive forest fragments benefit regional occurrence of forest-breeding birds by providing individuals to neighboring small woodlots. Limited reproduction in these small woodlots means that they may act as a reservoir for excess individuals in the case of catastrophic events that result in vacancies in source woodlots. Conservation and sound forest management of small forests should be directed particularly toward those closer to large regional forests. [ABSTRACT FROM AUTHOR]