Successo alimentare e attività di vigilanza della pavoncella Vanellus vanellus nei pascoli costieri del Parco Nazionale del Circeo (Lazio, Italia centrale)

Abstract

For two consecutive years (2008-09/2009-10) the feeding success and the vigilance activity of the lapwing Vanellus vanellus have been investigated in a wintering site along the coast of southern Latium. The foraging individuals spent 55.9% of time seeking and capturing prey, 42.8% in vigilance and 1.3% in aggressive behaviour. The lapwing had a feeding success (prey/minute) on average of 0.93. The density in the foraging areas did not affect significantly the feeding success. Individuals that feed in groups achieve a higher success than those feeding alone. The time spent in the activity of scanning increases in conditions of low density, the number of actions of scanning remains instead constant. The low feeding success is probably compensated by nocturnal feeding. The results of this survey show how this behaviour plays a fundamental role in the daily energy balance of lapwing in the Mediterranean environment.