JUKEMA J, TERPSTRA K & RIJPMA U (1995) Massive passage of Siskins Carduelis spinus on the Frisian islands in autumn 1993. LIMOSA 68 (3): 102-106.

Relatively large numbers of Siskins were captured on three of the Dutch Frisian islands in autumn 1993 (Tab 1, Fig. 1). Field observers confirmed that large numbers had been recorded passing through (Fig. 1). Adult males seemed to arrive earlier than adult females. Winglength hardly differed between the sexes and ages; average winglength of males was slightly longer (Tab. 2). Since all retraps occurred within weven days (Tab. 3) , the birds probably did not stay very long. The possible origin of these Siskins is discussed ##### Eurasian Siskin Carduelis spinus

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