| Abstract: | Waterfowl managers can effectively use simple population models to aid in making management decisions. We present a basic model of the change in population size as related to survival and recruitment. A management technique designed to increase survival of mallards (Anas platyrhynchos) by limiting harvest on the Chippewa National Forest, Minnesota, is used to illustrate the application of models in decision making. The analysis suggests that the management technique would be of limited effectiveness. In a 2nd example, the change in mallard population in central North Dakota is related to implementing programs to create dense nesting cover with or without supplementary predator control. The analysis suggests that large tracts of land would be required to achieve a hypothetical management objective of increasing harvest by 50% while maintaining a stable population. Less land would be required if predator reduction were used in combination with cover management, but questions about effectiveness and ecological implications of large scale predator reduction remain unresolved. The use of models as a guide to planning research responsive to the needs of management is illustrated. |
| Genre: | Article |
| ProdID: | 1001686 |
| Citation Author: | Cowardin, L. M.; Johnson, D. H. |
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| Citation End Page: | 35 |
| Citation Issue: | 1 |
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| Citation Language: | English |
| Citation Larger Work Title: | Journal of Wildlife Management |
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| Citation Number Of Pages: | 17 |
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| Citation Phsyical Description: | p. 18-35 |
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| Citation Search Results Text: | Mathematics and mallard management; 1979; Article; Journal; Journal of Wildlife Management; Cowardin, L. M.; Johnson, D. H. |
| Citation Start Page: | 18 |
| Citation Volume: | 43 |
| Citation Year: | 1979 |
| Type: | citation/reference |
| Text: | Mathematics and mallard management; 1979; Article; Journal; Journal of Wildlife Management; Cowardin, L. M.; Johnson, D. H. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Mon, 1 Jan 1979 00:00 -0600 |
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