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C. E. Korschgen

Publications and source records attributed to C. E. Korschgen.

29 records · Page 2Linked to original sources
USGS1992

Human disturbances of waterfowl: An annotated bibliography

The expansion of outdoor recreation greatly increased the interaction between the public, waterfowl, and waterfowl habitat. The effects of these interactions on waterfowl habitats are visible and obvious, whereas the effects of interactions that disrupt the normal behavior of waterfowl are subtle and often overlooked, but perhaps no less harmful than destruction of habitat. Resource managers and administrators require information on the types, magnitude, and effect of disturbances from human contact with wildlife. This bibliography contains annotations for 211 articles with information about effects of human disturbances on waterfowl. Indexes are provided by subject or key words, geographic locations, species of waterfowl, and authors.

Resource Publication↗
USGS1988

American wild celery (Vallisneria americana): Ecological considerations for restoration

The success of vegetation management programs for waterfowl is dependent on knowing the physical and physiological requirements of target species. Lakes and riverine impoundments that contain an abundance of the American wildcelery (Vallisneria americana ) have traditionally been favored by canvasbacks (Aythya valisineria ) and other waterfowl as feeding areas during migration. Information on the ecology of American wildcelery is summarized to serve as a guide for potential wetland restoration projects. Techniques are described for transplanting winter buds. Management programs that employ these techniques should define objectives clearly and evaluate the water regime carefully before initiating major restoration.

Technical Report↗
USGS1988

Feeding ecology of canvasbacks staging on Pool 7 of the Upper Mississippi River

Foods consumed by canvasback ducks (Aythya valisineria), food availability, and energetic relationships were studied on Navigation Pool 7 of the upper Mississippi River in 1978, 1979, and 1980. Canvasbacks fed primarily upon winter buds of American wildcelery (Vallisneria americana) and tubers of stiff arrowhead (Sagittaria rigida). In 1980, waterfowl consumed 40% of 380,160 kg of wildcelery winter buds on a portion of Pool 7 referred to as Lake Onalaska. Daily energy expenditure based on estimates from the literature suggests that individual canvasbacks require a minimum of 125 g (dry wt) of wildcelery winter buds each day. Extrapolation of use-days and the daily energy requirement suggests that 3,470 ha of wildcelery are required to support a canvasback population represented by 5 million use-days.

Book chapter↗