Foerageergedrag van een Waterspreeuw Cinclus c. cinclus in stilstaand water

A Dipper stayed at a stagnant pond (15x20 m) in the forest of Berkenheuvel (West-Drenthe) on 4 November 1993. Foraging bouts lasted 7, 10, 6, 5 and 5 min, the intermittent breaks 7, 9, 5, 4 and 1 min. All foraging took place by diving. Diving times (measured from video) were on average 3.1 sec (n=26, SD=1.55, range=0.5-6.2 sec). Diving was mostly restricted to the zone of shallow water (up to 75 cm) within three m from the shore. Catching rate was rather low, viz. on average 3.3 preys/min (n=29 minutes and 95 prey items, SD=I.36, range=l-6/min). Identified prey species consisted of larvae of Warty Newts Triturus vulgaris (15), Trichoptera (21), larvae of Odonata (10) and water beetles Hydrophilidae. Small prey items were also taken, but could not be identified (n=48). Handling time of large prey was on average 4.7 sec (n=6, SD=1.88). Newts and Chiroptera were vigorously shaken when caught and dismembered particles were eaten.