Zon-gedrag van een mannetje Sperwer Accipiter nisus

A radio-tagged adult male Sparrowhawk started preening in the full sun after having rested in the cover of a woodlot between 10.45-11.10 hr on 7 April 2001. It assumed a sunning posture for 30 seconds, with half-spread wings and tail, turning its back towards the sun. As soon as the sun disappeared, a normal stance was again adopted. An even shorter sunning posture was seen when the sun reappeared at 11.25 hr, this time only the left wing was half-spread and the longest primary rested on a branch. During the previous days, the weather had been adverse (cold, wet). Despite the fact that this male had a partner, he spent most of its time near the nest site, apparently neither hunting nor nest-building.