Invasion de Tarins ( Carduelis spinus ) au littoral belge en hiver 1965-1966. Réserve du Zwin à Knokke-sur-Mer (51°21'N., 3°18'E.)

The extraordinary invasion of siskins ( Carduelis spinus ) along the Belgian Coast during the 1965-1966 Winter, has been especially studied in the Bird Reserve of the «Zwin» at Knokke (51°2l'N., 3°18'E.) where 5.375 siskins were captured and ringed between October 1965 and May 1966. Out of these, 4.627 were ringed during the two months of December and January.The following subjects are treated :1. Causes of this invasion. Several possibilities are put forward; if these possibilities cumulate, this could explain the invasion. The siskin populations of Northern Europe travel by two different way... Mehr ...