Plastic intake by marine vertebrates has been widely reported, but information about its presence in continental waterfowl is scarce. Here we analyzed faeces of waterbirds species (European coot, Fulica atra, mallard, Anas platyrhynchos and shelduck, Tadorna tadorna) for plastic debris in five wetlands in Central Spain. We collected 89 faeces of shelduck distributed in four lakes, 43.8% of them presented plastic remnants. Sixty percent of 10 faeces of European coot and 45% of 40 faeces of mallard contained plastic debris. Plastic debris found was of two types, threads and fragments, and were identified as remnants of plastic objects used in agricultural fields surrounding the lakes. Differences in prevalence of plastic in faeces, number of plastic pieces per excrement and size of the plastic pieces were not statistically significant between waterfowl species. Thus, our results suggest that plastic may also be frequently ingested by waterfowl in continental waters, at least in our study area. Future studies should address this potential problem for waterbird conservation in other wetlands to evaluate the real impact of this pollutant on waterbirds living in inland water.

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Temporary inland wetlands are among the most threatened ecosystems worldwide, and recognition of the factors that determine species richness in different seasons is key for developing conservation plans for these systems. La Mancha Húmeda Biosphere Reserve in central Spain has many inland wetlands of this type, but the driving ecological processes of species richness are poorly understood. This study examines the association of landscape and local variables with species richness patterns of inland wetlands of La Mancha Húmeda Biosphere Reserve during winter and the breeding season. The number of lakes in several increasing radii was a proxy of connectivity, and maximum flooded surface and shoreline length were surrogates of the species–area relationship. Other landscape and local habitat variables, such as hydroperiod (length of inundation period), distance from human settlements, shoreline development index, vegetation surface cover, average lake depth, number of islands and surface area of islands were also analysed. Hierarchical partitioning analysis was used to evaluate the contribution of the environmental variables to explain the species richness of waders. Species richness (26 species, four threatened in Europe) had different associations with the variables during the wintering and breeding seasons. The richness of breeding and wintering species was positively associated with hydroperiod and maximum flooded surface area respectively. No variable measured was negatively associated with species richness in any season. Hydroperiod and flooded surface area are altered directly by human activities. Water extraction for irrigation reduces hydroperiod in some wetlands, whereas wastewater input extends hydroperiod in others, promoting wader concentrations in lakes flooded in summer and potentially favouring botulism outbreaks. In addition, the lack of protection and management on most of the lakes in La Mancha Húmeda Biosphere Reserve also favours encroachment of agriculture, destroying and degrading habitat for wintering and breeding waders.

Foraging habitat selection by gull-billed tern (Gelochelidon nilotica) in Central Spain (Castilla-La Mancha). The gull-billed tern breeds in temporary lakes in Castilla-La Mancha in Central Spain but depends on surrounding land habitats to feed its chicks. It is therefore vital to know the type of environments it selects to capture prey to feed nestlings. The aim of this study was to evaluate the use of habitats for hunting by adult gull-billed tern. Of 66 lakes monitored between 1996 and 2016, we found the gull-billed tern used 12 for breeding. Each lake was used during this period for 1-14 breeding seasons. We selected circular areas around the three wetlands where the species bred in 2013 and 2014. Within these circles, we sampled a total of 60 random points and recorded 125 gull-billed tern contacts (including between 1 and 39 birds). We estimated the same environmental variables at contact and random points, including land use and the distance to the nearest wetland, the nearest colony and to several types of anthropic uses (paved roads, houses, and cities). To evaluate habitat selection we calculated the Manly selection index for soil use variables, and fitted linear mixed models to evaluate differences in the distance variables. Land uses selected for foraging by the gull-billed tern were mainly cereal crops, whereas vineyards were avoided. The birds foraged on average up to 2 km from the colonies and tended to avoid proximity of towns and paved roads, suggesting that the species is sensitive to human disturbance. Vineyards are the main land use in this region and the intensity is increasing. Our results suggest vineyards should be limited in areas around these wetlands so that gull-billed terns may forage in their preferred sites.

RESUMEN: La Reserva de la Biosfera de La Mancha Húmeda es el principal grupo o red de lagunas de interior de la Península Ibérica donde poblaciones de aves acuáticas, con prioridad de conservación a nivel europeo, nidifican e invernan constituyendo un punto caliente para la conservación de la biodiversidad. En la actualidad, es uno de los complejos de humedales más amenazados en España y Europa debido a las actividades humanas, principalmente la agricultura, hasta el punto que en el año 2008 se propuso su descatalogación como Reserva de la Biosfera. Entre enero de 2007 y diciembre de 2010 se ha realizado un censo mensual en 10 lagunas localizadas en el Campo de San Juan (SE de Toledo, SO de Cuenca y NE de Ciudad Real) dentro de la Reserva de la Biosfera, presentando en este trabajo los resultados del seguimiento de las 12 especies catalogadas como SPEC 1 y 2 (BIRDLIFE INTERNATIONAL, 2004) reconocidas en este espacio geográfico. Los resultados muestran que dos especies, el porrón europeo (Aythya ferina) y la cigüeña común (Ciconia ciconia) son comunes y se encuentran ampliamente distribuidas en las lagunas estudiadas, siendo el porrón europeo la especie que ha mostrado el mayor tamaño poblacional. Cuatro especies (Ciconia nigra, Platalea leucorodia, Marmaronetta angustirostris y Numenius arquata) tienen una presencia ocasional y con muy bajos tamaños poblacionales, utilizando estas lagunas como lugar de descanso en sus rutas migratorias o movimientos dispersivos El resto de especies (Vanellus vanellus, Limosa limosa, Tringa totanus y Philomachus pugnax) presentan escasos efectivos demográficos, utilizando las lagunas de manera ocasional y distribuyéndose de manera discontinua. Cinco lagunas (Manjavacas, Camino de Villafranca, La Veguilla, Salicor y Pedro Muñoz) han presentado en algún momento del periodo de seguimiento de 8 a 10 de las especies inventariadas, todas ellas bajo protección legal como Reserva Natural. La profundidad de la lámina de agua, la presencia de orillas adecuadas, el desarrollo de helófitos, la presencia de nutrientes y las ca-