Consumptie van vlierbessen Sambucus nigra door Houtduif Columba palumbus

In 1998 and 1999 the foraging speed of Woodpigeons in a city garden was recorded. In 1998, the birds started foraging on 30 August and were last seen on 8 September. In 1999, they started and stopped earlier (Appendix 1). Mean foraging speed was 2.2 sec/berry, the maximum 1.2 sec/berry. Efficiency of foraging decreased at least with a factor two in the course of the observation period (Fig. I), probably because the ungainly pigeons preferred berries that were easy to reach. In both cases, exploitation by pigeons stopped after a group of -much more efficiently foraging- Starlings Sturnus vulgaris started feasting on the berries.