Diet differences in Redheads from nearshore and offshore zones in Louisiana

Thomas C. Michot; A.J. Nault

doi:10.2307/3809419

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Diet differences in Redheads from nearshore and offshore zones in Louisiana

Thomas C. Michot·A.J. Nault

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Abstract

Habitat management decisions for diving ducks in winter are limited by the lack of information concerning their use of nearshore and offshore zones. Therefore, we compared diets of redheads ( Aythya americana ) collected from nearshore (n = 206) and offshore (n = 72) zones during winters at the Chandeleur Islands, Louisiana, 1987-89. A greater (P < 0.05) proportion of redheads from nearshore had food in their esophagus and proventriculus than redheads from offshore. Feeding redheads in the offshore zone consumed more (P < 0.05) animal matter (42% in esophagus) and less plant material (58%) than conspecifics feeding nearshore (13% animal, 87% plant). Contents of proventriculi showed the same trend (P < 0.05). Zone-related diet differences occurred in both sexes and in early and late winter. Food availability and nutritional needs may affect these differences.

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Journal of Wildlife Management Article

Source-reported bounding extent: 29.58540020340835° to 30.073847754270204° latitude; -89.044189453125° to -88.74069213867188° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Thomas C. Michot, A.J. Nault. 1993. Diet differences in Redheads from nearshore and offshore zones in Louisiana. https://doi.org/10.2307/3809419

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