Prefledging mass recession in Manx shearwaters: parental desertion or nestling anorexia?

Citation
Cm. Gray et Kc. Hamer, Prefledging mass recession in Manx shearwaters: parental desertion or nestling anorexia?, ANIM BEHAV, 62, 2001, pp. 705-709
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences","Neurosciences & Behavoir
Journal title
ANIMAL BEHAVIOUR
ISSN journal
0003-3472 → ACNP
Volume
62
Year of publication
2001
Part
4
Pages
705 - 709
Database
ISI
SICI code
0003-3472(200110)62:<705:PMRIMS>2.0.ZU;2-I
Abstract
In many species of bird, nestlings undergo a period of mass recession, asso ciated with a large reduction in food provisioning, before they fledge. Thi s has been ascribed to parental desertion, although it could equally result from voluntary limitation of feeding (i.e. anorexia) among chicks. We exam ined the interactions between Manx shearwater, Puffinus puffinus, parents a nd chicks, to test whether the prefledging reduction in feeding was control led by parents, chicks or both. In a cross-fostering experiment, chicks of different ages were exchanged between nests. We predicted that under a pare ntal control model, cross-fostering would have no effect on food provisioni ng by the parents, but under chick control, the level of provisioning would be adjusted according to the age-specific requirements of the foster chick . Older chicks placed in the nests of younger chicks entered mass recession at an older age and had higher food-provisioning rates than unmanipulated chicks over the 10 days prior to fledging, supporting the parental control model. Younger chicks placed in the nests of older chicks had lower fledgin g masses than unmanipulated chicks, as a result of lower food-provisioning rates prior to fledging, which also supports this model. However, parents c ontinued to feed younger chicks beyond the date at which their own chick wo uld have fledged. This suggests that chicks also influenced food provisioni ng, and that mass recession resulted from interactions between a relatively fixed provisioning pattern in parents and age-specific food requirements o f chicks. (C) 2001 The Association for the Study of Animal Behaviour.