Absence of insular density inflation in Corsican Finches Carduelis [citrinella] corsicanus

Abstract

The insular syndrome predicts a number of differences between insular and mainland populations. One such prediction is that island populations tend to exhibit density inflation. This prediction was examined by comparing the population densities of mainland Citril Finches (central and south-west Europe) and insular Corsican (Citril) Finches (Mediterranean islands). Contrary to the hypothesis of density inflation in island populations, no indication of higher densities in Corsican Finches (0.6-2.1 pairs/10 ha) was found in comparison with Citril Finches (1.3 pairs/10 ha). In fact, population densities in the mainland population of the Catalan Pre-Pyrenees (7-10 pairs/10 ha) were extraordinarily high in comparison with all other study areas.