US Fish & Wildlife Service
Date of this Version
1992
Abstract
Egg temperatures and hen attentiveness were studied from 1989-91 on nests near sites known to have high selenium concentrations in an effort to document causes for nesting failures. Temperature and light sensitive radio transmitters were used to monitor incubation patterns in American coots (Fulica americana), mallards (Anas platyrhynchos), gadwalls (Anas strepera), northern shovelers, (Anas clypeata), and redheads (Aythya americana) nests. Mean temperatures of telemetered eggs placed in incubated nests ranged from 32.6°C to 37.8°C and differed only slightly from results obtained in other studies. We found no nesting failures among nests with low levels of selenium, attentive hens, and no predation or abandonment. However, nesting success of attentive hens experiencing no predation but incubating embryos containing high levels (> 10 μg/g dry weight) of selenium was poor (29%). Interrelationships of selenium concentrations and incubation patterns are discussed.
Comments
Published in Contaminant Report Number: R6/400S/92, 1-20, (1992)