The Effect of Isolation on the Number of Woodland Birds in Small Woods in the Netherlands

The effect of isolation of forest habitat islands on the number of breeding woodland birds was studied in thirty-six woodlots, varying in size and differing in degree of isolation. Various isolation variables were calculated. Multiple regression analysis showed that, apart from patch area, the amount of woodland near the forest island and the distance t o an extensive forest area have significant effects on the number of woodland birds. This result is not necessarily at variance with the apparent flying abilities of birds.