Publications

The response of game-farm mallards (Frost strain) to seven pharmacological immobilizing agents was evaluated in Phase I of a planned four-phase study. A limited amount of testing was also done with wild mallards. Single dosages were administered to determine the mean effective dose (ED50) and mean lethal dose (LD50), The therapeutic index, or safety factor (LD50/ED50), and palatability...

A technique for marking waterfowl ducklings less than 1 day old was developed to permit subsequent identification in the hand. Marking was accomplished by removing the alulae from wings of mallard (Anas platyrhynchos) ducklings with a small scissors or clipper. No differences in growth rate, behavior, or flight capability were noted between clipped and nonclipped birds. Thirty-five...

Cuterebra polita Coquillett is a primary parasite of the pocket gopher. Thomomys talpoides. in the western United States. It also occurs secondarily in other wild rodents that come into close contact with pocket gophers. Field studies disclosed pursuit, mating, and ovipositing at an aggregation site near Monte Cristo, Utah. Eggs were individually attached to fibrous roots suspended from...

This pamphlet describes how to make, install and care for inexpensive duck nesting baskets. Ducks have been attracted to these structures in the prairies of eastern North and South Dakota, western Minnesota, and northern Iowa. Nesting structures can help increase the number of local nesting ducks, especially mallards.

No abstract available.

Low water levels during critical phases of the breeding cycle appear to have caused population declines of waterfowl and other marsh birds on the Spring Run Game Management Area. Pair-counts indicated a decline from 70 pairs of waterfowl in 1965 to 2 pairs in 1968. Nest success of upland nesting blue-winged teal (Anas discors) averaged 33% and mallards (Anas platyrhyncos) averaged 23%...

Waterfowl populations and habitat characteristics were examined on 33 potholes in each of two 16-square-mile study areas of agricultural and nonagricultural land in southwestern Manitoba. The agricultural land potholes, lacking in or incompletely surrounded by trees, received greater use by lesser scaup (Aythya affinis), canvasback (A. valisineria), redhead (A. americana), coot (Fulica...

Abstract has not been submitted

A 4-year production study of upland nesting waterfowl on the Missouri Coteau area of North Dakota showed that pair numbers, nesting densities and nest success were generally reduced by grazing. It is suggested that cover removal such as regular grazing and mowing be discontinued on areas managed primarily for waterfowl production and that management practices which create dense rank...

Bursa of Fabricius depths of 88 lesser snow geese (Anser c. caerulescens) and 69 small Canada geese (Branta canadensis hutchinsii/parvipes complex) were measured. Bursal depths were unreliable indicators of age-classes of lesser snow geese and small Canada geese; previously, the same had been found to be true for large Canada geese (B. c. interior). Regression in size or closure of the...

A cable-chain device towed between two vehicles was developed for locating occupied duck nests in brushy, herbaceous, and grassy cover types. Twenty-three of 29 previously located gadwall (Anas strepera) and blue-winged teal (A. discors) hens were flushed from their nests with the drag for an efficiency of 79 percent. Eighty acres of nesting cover can be searched in 4-6 hours by the...

The validity of group counts, cannon-net catches, and hunter-bag checks for estimating productivity of lesser snow geese (Anser caerulescens caerulescens) and small Canada geese (Branta canadensis hutchinsii-parvipes complex) was studied at Sand Lake National Wildlife Refuge during the falls of 1965 and 1966. Age ratios of snow geese obtained from net-trapped samples were significantly...