Begging in common redstart nestlings: Scramble competition or signalling of need?

PORKERT, J. a ŠPINKA, Marek. Begging in common redstart nestlings: Scramble competition or signalling of need?. Ethology, 2006, 112, 398-410. ISSN 0006-3088.
Kateg. publikaceVědecké publikace impaktované
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Abstrakt

Begging behaviour by the young affects parental food distribution among nestlings of altricial birds. We present an analysis of two types of begging behaviour in common redstart (Phoenicurus phoenicurus).The model of scramble competition with competitiveasymmetries between nestlings or honest signalling model were used. Both gaping and nest positioning were affected by individual differences in nestling hunger and were in agreement with the honest signalling model. Those nestlings received food more often. Nestling movement seemed to be caused by the less hungry nestlings moving actively from front to rear positions. Low mortality of individual nestlings within broods that survived to fledging and small within-brood variation in fledging weights indicated low competition among nestmates. There are probably two behavioural mechanisms that contribute to the equalization of fledging weights: the signalling of need through gaping and the regular turnover of nestlings at front positions.

OdděleníEtologie