10 100 1,000 10,000 100,000 Forest size (ha)

Figure 25.2 Percentage of artificial nests preyed upon in relation to forest size. Closed squares are large forest tracts, open circles are rural fragments and closed circles are suburban fragments. The number beside each point refers to the artificial nests placed in that forest. The artificial nests were wicker baskets of the type sold in pet shops for canaries; they were lined with dry grass and three quail eggs were placed in each. Some 50 or 100 nests were employed in each of 11 tracts of forest, placed at 20 m intervals, alternately on the ground and at heights of 1-2 m in shrubs and saplings. After one week the nests were checked and any that had lost one or more eggs were classed as preyed upon. Redrawn from Wilcove (1985).

Was this article helpful?

0 0

Post a comment