Effects of Prior Nesting Success on Site Fidelity and Breeding Dispersal: An Experimental Approach

Based on more than 300 individually marked American Robins (Turdus migratorisu) and Brown Thrashers (Toxostoma rufum), I tested three hypotheses to explain low return rates of birds whose nesting attempts are unsuccessful: (1) birds with low reproductive success are low-quality individuals that are more likely to suffer mortality between breeding seasons; (2) nesting failure increases reproductive effort by causing birds to renest, and this...