Avian parental care under the risk of nest predation: General patterns and exceptions.

GHALAMBOR, C. K.; T. S. SILLETT; S. PELUC; T. E. MARTIN; J. YOON; H. R. SOFAER

Boulder, Colorado

Congreso; 31st Annual Meeting of the Western Field Ornithologists; 2006

Variation in parental care results from differences in the fitness costs and benefits associated with providing care. In birds with dependent young in the nest, parents must weigh the benefits of providing food to their offspring against the costs of attracting the attention of nest predators. Here, we review the relationship between nestling provisioning rates and the risk of nest predation. We find a strong interspecific pattern between increasing probability of nest predation and (1) a decrease in mean nestling feeding rates, and (2) an increase in the magnitude of change in nestling feeding rates when faced with an immediate risk of predation. However, comparisons of some populations with similar rates of nest predation but very different nestling provisioning rates suggest that such correlations can be misleading without more detailed information about the predator community.