Life Sciences Commons^™

Breeding Patterns Of Eastern Phoebes In Kansas: Adaptive Strategies Or Physiological Constraint?, Michael T. Murphy

Biology Faculty Publications and Presentations

Data were collected on annual (1980-1983) and seasonal (spring vs. summer) variation in reproduction by the double-brooded Eastern Phoebe (Sayornis phoebe) to test the proposal that phoebes modify reproductive patterns on a seasonal basis and switch from being brood survivalists in spring to brood reductionists in summer. Clutch size did not differ between spring and summer broods nor among years, but spring nests fledged one more nestling than summer nests. In 1981 breeding began earlier, eggs were larger, and nestlings grew faster than in all other years. Clutch size and egg mass within spring clutches increased seasonally. Egg mass was …