Effects of the features of contemporary occidental cities on urban avifauna
Desde los primeros asentamientos humanos permanentes del Holoceno, hace 10 000 años, hasta las ciudades contemporáneas, las aves han cohabitado con los seres humanos. En las últimas décadas la urbanización ha crecido exponencialmente en el planeta y, en 2030, más del 60% de la población mundial vivirá en zonas urbanas. En función de su tolerancia a la urbanización las aves se clasifican en tres categorías: evitadoras, adaptadoras o explotadoras urbanas. Las ciudades occidentales contemporáneas atraen a las aves por la presencia de recursos tróficos abundantes y predecibles, la reducción en la diversidad de depredadores o la provisión de estructuras donde ubicar los nidos, entre otras. Sin e…
Survival Rates of Young MagpiesPica picain a Mountain Population of Eastern Spain
Abstract. The aim of this study was to estimate the survival of young Magpies between fledging and the next breeding season and to identify some of the factors affecting it. A total of 50 nestlings were colour-ringed in two breeding seasons in the valley of the Pitarque River (Teruel, E Spain), and were monitored weekly until May of the following year. 59 nestlings were also colour-ringed in two nearby localities (4–5 km) to detect possible dispersal to and from our study area. Mark-recapture analyses were used to estimate weekly survival, which was assumed to be constant for periods of four weeks in order to reduce the number of parameters. Models with the effect of time, age class, season…
Habitat fragmentation compromises the population dynamic of the globally near-threatened Straight-billed Reedhaunter (Limnoctites rectirostris)
AbstractUnderstanding the consequences of habitat fragmentation to biological populations is crucial to develop sound conservation polices. The Straight-billed Reedhaunter (Limnoctites rectirostris) is a little known and threatened Passeriform that is highly dependent Erygo wetlands patches. Here, we evaluated the effects of habitat fragmentation on populations of the Straight-billed Reedhaunter, during the construction of a water reservoir in southern Brazil. During eight months, we monitored five Eryngo wetlands patches occupied (n=3) and no occupied (n=2) by Straight-billed Reedhaunter individuals, collecting data on their temporal occupancy patterns and registering new fragmentation eve…