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USGS · 1001380

Diet of canvasbacks during breeding

J. E. Austin·J.R. Serie·J.H. Noyes
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Abstract

We examined diets of canvasbacks (Aythya valisineria) breeding in southwestern Manitoba during 1977-81. Percent volume of animal foods consumed did not differ between males and females nor among prenesting, rapid follicle growth, laying, incubation, and renesting periods in females (mean = 50.1%). Tubers and shoots of fennelleaf pondweed (Potamogeton pectinatus) and midge larvae (Chironomidae) were the predominant foods, comprising on average 45% and 23% of the diet volume, respectively. Continued importance of plant foods to canvasbacks throughout reproduction contrasts with the mostly invertebrate diets of other prairie-breeding ducks, and does not fit current theories of nutritional ecology of breeding anatids (i.e., females meet the protein requirements of reproduction by consuming a high proportion of animal foods).

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Prairie NaturalistArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 48.86471476180277° to 51.56341232867588° latitude; -101.6015625° to -98.5693359375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

J. E. Austin, J.R. Serie, J.H. Noyes. 1990. Diet of canvasbacks during breeding. https://pubs.usgs.gov/publication/1001380

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