Population change and potential food base of the shorebirds on the Nagy-szik of the Hortobágy (preliminary results)
Abstract
Sodic lakes are unique habitats in the Carpatian Basin, with special water cycles and chemical parameters. These habitats are important in conservation biology, because they hold many protected plants and animals. Unfortunately, many sodic lakes have been declining in the last decades due to the decrease of the ground water table, and the changes in water regimen and in organic matter circulation. Nagy-szik is a declining sodic lake near Balmazújváros (Hortobágy, E-Hungary) and is undergoing habitat restoration from 2010 to 2013 aiming the recovery of the natural state of this area. Here we study factors, which may positively influence the nesting of shorebirds. We recorded the density of nesting shorebirds and estimate the potential aquatic and terrestrial food sources and their density as well as the changes occuring after the habitat restoration. Compared to 2010 in 2011 we finded increase in the number of specimen and species of nesting shorebirds. Positive change will caused by effect of the habitat restoration and extremely wet 2010 year. Based on the previous literary data, we determined that the sampled invertebrates are suitable for the analysis of the potencial food base of shorebirds.
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