Ecological Peculiarities of Nesting and Reproduction of the Common Oystercatcher (Haematopus ostralegus longipes Buturlin, 1910) (Haematopodidae, Charadriiformes) in the Medveditsa River Channel

Abstract

The population of the continental oystercatcher subspecies in the conditions of the middle reaches of the Medveditsa River in the nesting period of 1996–2008 was stable, namely, three pairs, out of which two, rarely three, nested annually. The clutch size was 2–3 eggs. Our many-year survey has established a tendency toward a significant decrease in the reproductive success against the background of transformations of nesting and feeding habitats, which is determined by the long-term tendency toward a reduction in the water level in the river.