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USGS · 70208572

Diurnal time-activity budgets of wintering canvasbacks in Louisiana

William L. Hohman·D.P. Rave
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Abstract

We determined diurnal time-activity budgets of Canvasbacks ( Aythya valisineria ) at Catahoula Lake and at the Mississippi River Delta, Louisiana, from December 1987 to March 1988. Canvasback feeding, resting, locomotory, and comfort activities varied by month and location with a month-location interaction. Moreover, the percentage of time spent feeding varied by sex with a month-sex interaction. Study site differences in the time- activity budgets of wintering Canvasbacks may be related to characteristics of their foods, foraging mode, disturbance level, and physical features of habitats at the two study sites. Canvasbacks wintering in Louisiana generally spent less time feeding and more time resting during the day than they did in Mississippi or coastal South Carolina. Levels of agonistic behavior were lower than those observed in South Carolina. We found no evidence of male dominance of female Canvasbacks in Louisiana.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 29.198325299972065° to 31.587894464070395° latitude; -92.2357177734375° to -89.19868469238281° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

William L. Hohman, D.P. Rave. 1990. Diurnal time-activity budgets of wintering canvasbacks in Louisiana. https://pubs.usgs.gov/publication/70208572

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