Synchronous provisioning increases brood survival in cooperatively breeding pied babblers
Article first published online: 6 AUG 2009
© 2009 The Authors. Journal compilation © 2009 British Ecological Society
Journal of Animal Ecology
Volume 79, Issue 1, pages 44–52, January 2010
How to Cite
Raihani, N. J., Nelson-Flower, M. J., Moyes, K., Browning, L. E. and Ridley, A. R. (2010), Synchronous provisioning increases brood survival in cooperatively breeding pied babblers. Journal of Animal Ecology, 79: 44–52. doi: 10.1111/j.1365-2656.2009.01606.x
- Issue published online: 11 DEC 2009
- Article first published online: 6 AUG 2009
- Received 16 February 2009; accepted 7 July 2009Handling Editor: Fanie Pelletier
- cooperative breeding;
- nestling predation;
- parental care;
- pied babbler;
1. Behavioural synchrony typically involves trade-offs. In the context of foraging, for example, synchrony may be suboptimal when individuals have different energy requirements but yield net benefits in terms of increased foraging success or decreased predation risk.
2. Behavioural synchrony may also be advantageous when individuals collaborate to achieve a common goal, such as raising young. For example, in several bird species, provisioners synchronize nest-feeding visits. However, despite the apparent prevalence of provisioning synchrony, it is not known whether it is adaptive or what its function might be.
3. Here, we propose a novel explanation for provisioning synchrony: it increases brood survival by decreasing the number of temporally separate nest visits and accordingly the chance that the nest will be detected by predators. Using cooperatively breeding pied babblers, we showed experimentally that provisioners synchronized nest visits by waiting for another provisioner before returning to the nest. Brood survival increased with provisioning synchrony. Provisioners were more likely to synchronize feeding visits for older nestlings as they were louder and possibly more conspicuous to predators. Finally, provisioners in large groups were more likely to wait for other provisioners and synchronized a higher proportion of all visits than those in smaller groups. Thus, provisioning synchrony may be one mechanism by which large groups increase brood survival in this species.
4. This study highlights a novel strategy that birds use to increase the survival of young and demonstrates the advantages of coordinated behaviour in social species.