HUNTING BEHAVIOR AND TIME BUDGET OF WOODC HAT SHRIKES LANIUS SENATOR IN NORTHERN SWITZERLAND

SCHAUB M

M. Schaub, HUNTING BEHAVIOR AND TIME BUDGET OF WOODC HAT SHRIKES LANIUS SENATOR IN NORTHERN SWITZERLAND, Journal fur Ornithologie, 137(2), 1996, pp. 213-227

15

TEDESCO

Article

Ornithology

Journal fur Ornithologie → ACNP

0021-8375

137

2

1996

213 - 227

ISI

0021-8375(1996)137:2<213:HBATBO>2.0.ZU;2-F

The hunting behavior of Woodchat Shrike in Northern Switzerland was st udied by visual observations of five pairs in 1994. Data on food suppl y were collected by standardized observations in half-circles of 1 m r adius. During warm and dry weather the activity of the insects increas ed. More insects were seen in high than in short vegetation. The Woodc hat Shrikes either hunted on the ground (64% of all hunting flights) o r in the air (36%). The energy gain in ground-huntings was higher than in flycatching due to larger average prey size and a shorter hunting distance, Ground huntings occured mainly in areas with short vegetatio n (7 cm high on average). The birds only fed on arthropods, preferring larger seizes. During bad weather they were dependant also on smaller prey. The proportion of time the adults spent in flight was longest d uring the nestling season. In load weather, hunting activity was sligh tly increased during incubation and nestling stage but low before incu bation and after fledging of the young. For hunting over short vegetat ion the birds seemed to spent less time in flight than for hunting ove r high vegetation.