Nutrition and Timing of Nesting in Greater Scaup

Research on Sea Ducks

This project examined the relationships of nutrition and physiology to timing of reproduction by Greater Scaup in coastal Alaska. Specific project goals included determining when and where energy and nutrients needed for clutch formation are acquired, the effect of nutritional status on timing of reproduction, and correspondence of circulating levels of yolk precursers with reproductive status.

We found that Greater Scaup females employ an unusual strategy of nutrient acquisition and allocation for clutch formation, in comparison to other ducks. They store nutrients on breeding areas, delay initiation of clutch formation until nutrient storage thresholds are achieved, but paradoxically do not invest stored nutrients into eggs. Instead, nutrient stores are likely used during incubation, reducing the need for incubation breaks and the corresponding increase in nest predation risk. We also demonstrated, for the first time, the utility of using circulating levels of plasma yolk precursors as an indicator of reproductive status in waterfowl.

CWE Researchers on this project:
Dan Esler
Tony Williams
Kristen Gorman

Research Partners:

Paul Flint