RAPTORS IN HUMAN LANDSCAPES: 125-135 (1996)
B.-U. Meyburg et al.
The Osprey in Germany: Its Adaptation to Environments Altered by Man
Bemd-U. Meyburg, Otto Manowsky und Christiane Meyburg
As a regular breeding species in Central Europe the osprey is presently confined to the Federal States of Mecklenburg-Vorpommern and Brandenburg in eastern Germany, and Pomerania and Mazuria in Poland. This is probably due to human persecution, especially in earlier decades. In Mecklenburg the population reached its lowest level with only 37 pairs in the DDT-period between 1968 and 1972. In Brandenburg, a slow but steady increase has occurred, from ca. 45-50 pairs in the early 1980s to over 120 pairs today. There has probably been a relationship between contamination with pesticides, reproductive success and population development which, however, has been very poorly studied. One limiting factor for the osprey population may have been the scarcity of suitable trees for nesting. The species prefers the tops of isolated old trees or trees on the edge of the forest dominating the adjacent trees. Due to forestry, such trees have become increasingly rare to the point that only a small fraction of the osprey population can nowadays reproduce in the traditional way. Fortunately, ospreys started to breed on power lines as early as 1938. On the pylons the nests are apparently safer than in trees. Nowadays over 75% of ospreys nest on these artificial structures in Germany, although no such breeding is known in Poland. This important adaptation may have helped the species to recover. The breeding success of 258 tree-nests and 366 nests on power-lines was studied. While the tree-nesting population remained rather stable, the pylon nesters strongly increased. On average, pylon-nesting ospreys produced more young than tree-nesting ospreys.
Keywords: osprey; Germany; Poland; breeding success; pylon-nesting; tree-nesting.Bernd-Ulrich & Christiane Meyburg, Wangenheimstr. 32, D-14193 Berlin
Otto Manowsky, Schönebecker Str. 12, D-16247 Joachimsthal