Immediate effects of capture on nest visits of breeding blue tits, Cyanistes caeruleus, are substantial
Publication Type: |
Journal Article |
Year of Publication: |
2015 |
Authors: |
Emmi Schlicht, Bart Kempenaers |
Publication/Journal: |
Animal Behaviour |
Keywords: |
blue tit, capture, cyanistes caeruleus, feeding, handling, human disturbance, nest visit, parental care, trapping |
ISBN: |
0003-3472 |
Abstract:
Although capture, handling and marking of birds as well as taking samples from them are ubiquitous and, in most cases, unavoidable procedures in ornithological research, their immediate effects on the individuals remain largely unstudied. Here, we present data over 3 years from a long-term field study on the breeding biology of the blue tit. Parents were captured at the nest when feeding 9–11-day-old young. For all birds, we measured the time of their first visit to the nest after capture and could thus establish their latency of return to the nest. After capture, parents stayed away a surprisingly long time (average 4.2 h, up to 18 h) and nests were not visited by either parent for a duration that almost never occurred under natural conditions. Parental return latencies were strongly associated with previous captures. Birds caught, marked and sampled previously returned on average 4.4 h earlier than new birds. Still these birds took on average 1.9 h to return. Thus, capture itself can have strong effects on immediate behaviour. Once the birds returned to the nest, the time between nest visits was similar to that observed before capture, indicating that birds resumed normal feeding activities. Return latencies of parents and the time nests were left alone had no long-term effects on offspring or breeding success. We discuss possible causes of delayed parental return and methodological implications.