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Résumé :
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From 1999 to 200 1, the population size of Lapwing as well as its hatching and breeding success I was investigated with standard methods in three areas under agricultural use in the Wummeniederung northeast of Bremen: nature reserve 'Borgfelder Wummewiesen' (677 ha), 'Fischerhuder I Wummeniederung' (1,437 ha) and 'Oberneulander Wiesen' (225 ha). In the whole study area (2339 ha) a total of 89, 93 and 52 breeding pairs was found in the respective years. In absence of crops, Lapwings were breeding on meadows and pastures of the 'Borgfelder Wummewiesen'. Tit the other study areas they were breeding mostly on crops. In the 'Borgfelder Wummewiesen' the Lapwing was protected against agricultural loss by law, in the 'Oberneulander Wiesen' by clutch saving. In the 'Fischerhuder Wummeniederung' there was no such protection. In contrast I to the clutch saving, low-intensity farming did not result in a higher breeding success. It is possible that low intensity farming increased the predation pressure. Low-intensity farming and higher water levels can change the habitat structure, thereby decreasing the possibility of compensating predation by second or third clutches. Data from the investigations in hatching and breeding success seem to support this hypothesis. A single field protection based on monitoring 1 results could be a way to overcome such problems with the possibility to protect not only those 1 clutches actually found.
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