Nestelende Houtduiven Columba palumbus in Assen

In 1980-2000 Woodpigeon numbers sharply declined in rural landscapes and woodland in the Province of Drenthe. At the sometime numbers in villages and towns increased and in the street where I live the Woodpigeon is the most numerous breeding bird with a local density of four pairs one the hectare in front of my balcony. In March through May 2005 a pair three times attempted to build a nest in a Thuya at a distance of 2 m from my balcony. The activities of this pair could be followed at an almost daily rate. At the first attempt eggs were laid, but the nest sagged and the eggs rolled out of the nest. During the second attempt at exactly the same place the nest was destroyed by a storm before eggs were laid. At the third attempt the pair managed to build a firmer nest on the same position and succeeded to produce chicks that were predated upon at an age of about 10 days. In the end of June my observations stopped and the pair may have bred successfully in the vicinity. In December after most trees had shed leaves, I mapped all Woodpigeon nests in my street using a GPS (Fig. 1). Some nests are clustered, based on information about territory borders in March-June. The distribution of nests is uneven, what cannot be explained by the distribution of suitable nesting sites (bushes and trees) which are available throughout the area. Possibly the presence of two territories (nests in Fig. 1) of Carrion Crows is, who often harass the Woodpigeons and presumably predate upon eggs and young is a factor that influenced distribution.