10 resultados para Cotinga


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In this paper we present a list of plant species whose fruits are eaten by eight cotinga species (Carpornis cucullatus, C. melanocephalus, Laniisoma elegans, Lipaugus lanioides, Oxyruncus cristatus, Phibalura flavirostris, Procnias nudicollis, and Pyroderus scutatus) at Parque Estadual Intervales (PEI), an Atlantic Forest reserve in southeast Brazil. Besides providing a list of fruits eaten by cotingas, our goal is to allow insights into fruit use by these birds whose ecology is poorly known. From 1990 to 2001 four sites located within PEI were regularly visited. These sites form an altitudinal gradient (70-800 m a.s.l.) and also a gradient of forest disturbance (second-growth to old-growth vegetation). Feeding records were made along several trails and dirt roads that crossed the study sites. Cotingas ate a variety of fruits (99 species in 34 families) that ranged from small (< 5 mm diameter) to large (up to 37 mm) and included some non-ornithochorous ones. With the exception of P. nudicollis, cotingas exploited not only fruits typical of the forest interior but also fruits of secondary vegetation, suggesting that concerning fruit exploitation early successional vegetation does not represent a barrier for the survival of these cotingas.

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We describe the nests and nesting behaviour of six little-known birds from south-central Minas Gerais, Brazil: Red-and-white Crake Laterallus leucopyrrhus (closed/ovoid/base nest with shells of white eggs), White-throated Woodcreeper Xiphocolaptes albicollis (cavity/without-tunnel/simple/platform nest with two immaculate white eggs), Southern Bristle Tyrant Phylloscartes eximius (closed/globular/lateral nest), Sharp-tailed Tyrant Culicivora caudacuta (high cup/lateral nest with three cream-coloured eggs), White-rumped Monjita Xolmis velatus (low cup/base nest with two immaculate white eggs) and Hellmayr's Pipit Anthus hellmayri (low cup/base nest with three pale brown eggs spotted dark brown).

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Documenting changes in distribution is necessary for understanding species' response to environmental changes, but data on species distributions are heterogeneous in accuracy and resolution. Combining different data sources and methodological approaches can fill gaps in knowledge about the dynamic processes driving changes in species-rich, but data-poor regions. We combined recent bird survey data from the Neotropical Biodiversity Mapping Initiative (NeoMaps) with historical distribution records to estimate potential changes in the distribution of eight species of Amazon parrots in Venezuela. Using environmental covariates and presence-only data from museum collections and the literature, we first used maximum likelihood to fit a species distribution model (SDM) estimating a historical maximum probability of occurrence for each species. We then used recent, NeoMaps survey data to build single-season occupancy models (OM) with the same environmental covariates, as well as with time- and effort-dependent detectability, resulting in estimates of the current probability of occurrence. We finally calculated the disagreement between predictions as a matrix of probability of change in the state of occurrence. Our results suggested negative changes for the only restricted, threatened species, Amazona barbadensis, which has been independently confirmed with field studies. Two of the three remaining widespread species that were detected, Amazona amazonica, Amazona ochrocephala, also had a high probability of negative changes in northern Venezuela, but results were not conclusive for Amazona farinosa. The four remaining species were undetected in recent field surveys; three of these were most probably absent from the survey locations (Amazona autumnalis, Amazona mercenaria and Amazona festiva), while a fourth (Amazona dufresniana) requires more intensive targeted sampling to estimate its current status. Our approach is unique in taking full advantage of available, but limited data, and in detecting a high probability of change even for rare and patchily-distributed species. However, it is presently limited to species meeting the strong assumptions required for maximum-likelihood estimation with presence-only data, including very high detectability and representative sampling of its historical distribution.