EFFECTS OF FOREST FRAGMENTATION ON A GUILD OF WINTERING PASSERINES: THE ROLE OF HABITAT SELECTION

摘要: Abstract This study analyses the winter colonization of an archipelago 31 forests (0·1–350 ha) in central Spain by guild pariforms ( Parus, Aegithalos, Regulus, Sitta and Certhia ). Two hypotheses are considered: (a) that birds with similar habitat preferences tend to disappear simultaneously reduction forest size, leading a ‘nested’ pattern species distribution; or (b) smallest random sample those found larger ones. The results support hypothesis (a). depend on relatively scarce resources, such as tree trunks junipers Juniperus thurifera europaea, brachydactyla, Parus cristatus P.ater ) only occupied largest forests. On other hand, exploit abundant, ubiquitous holm oak Quercus ilex foliage Regulus ignicapillus caeruleus ), were distributed uniformly throughout all fragments. These emphasize need for better understanding selection when designing conservation strategies fragmented populations.