Publications

We studied duck nest success and predator community composition in relation to size of discrete patches of nesting cover in the Prairie Pothole Region (PPR) of the United States in 1993-95. We focused on nests in uplands that were seeded to perennial grasses and forbs and enrolled in the Conservation Reserve Program (CRP) in Minnesota, North Dakota, and South Dakota. We estimated daily...

No abstract available.

No abstract available.

We developed a surface-associated activity trap (SAT) for sampling aquatic invertebrates in wetlands. We compared performance of this trap with that of a conventional activity trap (AT) based on non-detection rates and relative abundance estimates for 13 taxa of common wetland invertebrates and for taxon richness using data from experiments in constructed wetlands. Taxon-specific non...

White-tailed deer (Odocoileus virginianus) were videotaped depredating four songbird nests in grassland habitats in southeastern and northcentral North Dakota, 1996-1999. Deer ate two Savannah sparrow (Passerculus sandwichensis), two grasshopper sparrow (Ammodramus savannarum), one clay-colored sparrow (Spizella pallida), one red-winged blackbird (Agelaius phoeniceus) and three brown...

We examined the relationship between local water conditions (measured as the percent of total area of basins that was covered by water) and clutch size, egg volume, and hatchling mass of Mallards (Anas platyrhynchos) and Gadwalls (A. strepera) on four study sites in the Prairie Pothole Region of North Dakota and Minnesota, 1988-1994. We also examined the relationship between pond density...

No abstract available.

We studied interactions of reintroduced wolves (Canis lupus) with bison (Bison bison) in Yellowstone National Park. Only 2 of 41 wolves in this study had been exposed to bison before their translocation. Wolves were more successful killing elk (Cervus elaphus) than bison, and elk were more abundant than bison, so elk were the primary prey of wolves. Except for a lone emaciated bison calf...

We used simple linear regression to analyze 8-23 years of data on a wolf (Canis lupus) population and human harvest of white-tailed deer (Odocoileus virginianus) bucks in northeastern Minnesota to determine any effects of wolves on buck harvesting. Over the long term, wolves accounted for at least 14-22% of the inter-year variation in buck harvest in the region, but an unknown amount of...

Wolf (Canis lupus) depredations on livestock cause considerable conflict and expense in Minnesota. Furthermore, claims are made that such depredations are fostered by the type of animal husbandry practiced. Thus, we tried to detect factors that might predispose farms in Minnesota to wolf depredations. We compared results of interviews with 41 cattle farmers experiencing chronic cattle...

We used VHF, GPS and satellite radiocollars to study details of long distance movements by four Minnesota wolves (Canis lupus). Number of locations during our tracking ranged from 14 to 274. Farthest distances reached ranged from 183–494 km, and minimum distances traveled (sums of line segments) ranged from 490–4251 km. Numbers of times wolves crossed state, provincial or interstate...

In order to estimate mallard (Anas platyrhynchos) production from managed and unmanaged lands, waterfowl biologists need measurable predictors of brood survival. We evaluated effects of percent of seasonal basins holding water (WETSEAS), percent of upland landscape in perennial cover (PERNCOVER), rainfall (RAIN), daily minimum ambient temperature (TMIN), hatch date (HATCHDATE), brood age...