Nest defence by lapwings: Observations on natural behaviour and an experiment

Lapwings Vanellus vanellus are ground-nesting waders and they protect their nests by aggressively attacking predators near their nests. We investigate d the response of parents to natural predators and a dummy Hooded Crow Corv us [corone] cornix during the incubation period. First, we investigated whe ther the presumed value of offspring influenced defence behaviour. We found no evidence that clutch volume or the number of days the clutch had been i ncubated for influenced either the frequency of attacks or the time spent o n attacks. The density of nests decreased over the breeding season, and bot h the frequency of attacks and the time spent on attacks decreased with nes t density. Second, we found that male Lapwings were more active in defence than females. In particular, male Lapwings attacked natural predators more often than females and they spent more time on attacks than females. These results were corroborated by the dummy experiment.