The wintering of migrant Dunnocks Prunella modularis in two Mediterranean habitats after fire

Abstract

Migrant Dunnocks Prunella modularis are common winter visitors to the Mediterranean area. In a burnt forest, Dunnocks were present from October to April. They occupied definite individual home ranges of 0.18 ha on average (n = 83), at a density of 30 birds/10 ha in the fifth winter and 18 birds/10 ha in the sixth winter following a fire. Birds used visible posts and uttered ‘tseep’ calls often. Counter-calling was particularly frequent in the winter with the highest population density. In a burnt maquis, Dunnocks showed return rates (15%) and median recapture distances (62.5 m) not significantly different from those of territorial wintering Robins Erithacus rubecula. We suggest that Dunnock ranges can be regarded as ‘feeding territories’, promoted by an abundant, predictible and renewable food supply of rock-rose Cistus spp. seeds, characteristic of early Mediterranean successions. Ownership might be proclaimed by ‘tseep’ calls, recalling the behaviour of female Dunnocks during prebreeding territorial conflicts. Further research using colour-ringed birds may confirm Dunnock winter territoriality, exceptional for a migrant and mostly granivorous passerine.