Publications
This list of publications includes peer-review journal articles, official USGS publications series, reports and more authored by scientists in the Ecosystems Mission Area. A database of all USGS publications, with advanced search features, can be accessed at the USGS Publications Warehouse.
Filter Total Items: 41778
Mathematics and mallard management
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 i
Authors
L.M. Cowardin, D. H. Johnson
An apparatus for the continuous generation of stock solutions of hydrophobic chemicals
No abstract available.
Authors
W.H. Gingerich, W.K. Seim, R.D. Schonbrod
Fall foods of migrant common snipe in North Dakota
Abstract has not been submitted
Authors
E. K. Fritzell, G.A. Swanson, M.I. Meyer
Canvasback duck recovers from compound luxation to wing
Abstract has not been submitted
Authors
H. A. Doty
Forty-second breeding bird census - Kentucky blue grass prairie
Abstract has not been submitted
Authors
D. H. Johnson
Annual cycle of plasma luteinizing hormone and sex hormones in male and female mallards (Anas platyrhynchos)
Comparisons between 'wild'and 'game farm' mallards (Anas platyrhynchos) were made to assess the differences in the temporal changes of plasma hormones. Seasonal variation in the levels of immunoreactive luteinizing hormone (LH), testosterone, 5 -dihydrotestosterone (DHT), estrone, estradiol-17i?? and progesterone were measured in male and female mallards. In all birds there was a vernal increase i
Authors
R.S. Donham
Age-related aspects of mallard reproduction
Abstract has not been submitted
Authors
G.L. Krapu, H. A. Doty
Duck nest structure evaluations in prairie wetlands
Abstract has not been submitted
Authors
H. A. Doty
Age determination of mallards
A technique for distinguishing adult from yearling wild mallards (Anas platyrhynchos), from late winter through the nesting season, was developed by applying discriminant analysis procedures to selected wing feather characters of 126 yearlings and 76 adults (2-year-olds) hand-reared from wild eggs during 1974, 1975, and 1977. Average values for feather characters generally increased as the birds a
Authors
G.L. Krapu, D. H. Johnson, C.W. Dane
Mate preference in wild and domesticated (game-farm) mallards: II. Pairing success
Experiments were designed to determine whether assortative mating occurs in wild and game-farm mallard strains (Anas platyrhynchos). Mallard males of either strain raised with females of their own strain courted females of their own strain more than females of the opposite strain, and these males were only successful in pairing with females of their own strain. Males raised with females of the opp
Authors
K.M. Cheng, R.N. Shoffner, R.E. Phillips, F.B. Lee