AVIS-IBIS

Birds of Indian Subcontinent

Nest Predation and Circulating Corticosterone Levels within and among Species (Variación Intra- e Interespecífica en la Tasa de Depredación en Nido y Niveles Circulantes de Corticosterona)

Publication Type:Journal Article
Year of Publication:2011
Authors:Fontaine, JJ, Arriero, E, Schwabl, H, Martin, TE
Journal:The Condor
Volume:113
Issue:4
Date Published:2011
ISBN Number:00105422
Keywords:Emberizidae, Junco, Junco hyemalis
Abstract:Abstract Variation in the risk of predation to offspring can influence the expression of reproductive strategies both within and among species. Appropriate expression of reproductive strategies in environments that differ in predation risk can have clear advantages for fitness. Although adult-predation risk appears to influence glucocorticosteroid levels, leading to changes in behavioral and life-history strategies, the influence of offspring-predation risk on adult glucocorticosteroid levels remains unclear. We compared total baseline corticosterone concentrations in Gray-headed Juncos (Junco hyemalis dorsalis) nesting on plots with and without experimentally reduced risk of nest predation. Despite differences in risk between treatments, we failed to find differences in total baseline corticosterone concentrations. When we examined corticosterone concentrations across a suite of sympatric species, however, higher risk of nest predation correlated with higher total baseline corticosterone levels. As found previously, total baseline corticosterone was negatively correlated with body condition and positively correlated with date of sampling. However, we also found that corticosterone levels increased seasonally, independent of stage of breeding. Nest predation can alter the expression of birds' reproductive strategies, but our findings suggest that total baseline corticosterone is not the physiological mechanism regulating these responses.
URL:http://www.jstor.org/stable/10.1525/cond.2011.110027
Short Title:The Condor
Taxonomic name: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith