Douglas Johnson
Douglas Johnson is a Research Statistician (Emeritus) for the USGS Northern Prairie Wildlife Research Center in Jamestown, North Dakota.
Science and Products
Filter Total Items: 311
Conservation Reserve Program and migratory birds in the northern Great Plains
U.S. Department of Agriculture programs have mediated supply and demand of commodities and maintained the agricultural industry, but several programs have also offered various kinds of conservation benefits. The 1985 Food Security Act (Farm Bill) featured the Conservation Reserve Program (CRP), which paid farmers to plant perennial cover on highly erodible lands and to leave this land intact for a
Authors
Douglas H. Johnson, Rolf R. Koford
Contributions of the Conservation Reserve Program to populations of breeding birds in North Dakota
Previous studies have shown that habitat provided by the Conservation Reserve Program (CRP), a feature of the 1985 farm bill, is used by many birds. The present study quantitatively assesses the importance of the CRP by estimating changes in breeding-bird populations of North Dakota projected if CRP land would revert to cultivation. Of 18 species that were common in CRP or crop fields or both, 12
Authors
D. H. Johnson, L.D. Igl
Using known populations of pronghorn to evaluate sampling plans and estimators
Although sampling plans and estimators of abundance have good theoretical properties, their performance in real situations is rarely assessed because true population sizes are unknown. We evaluated widely used sampling plans and estimators of population size on 3 known clustered distributions of pronghorn (Antilocapra americana). Our criteria were accuracy of the estimate, coverage of 95% confiden
Authors
K.M. Kraft, D. H. Johnson, J.M. Samuelson, S.H. Allen
Bird censuses 123-128: Kentucky bluegrass prairie and mixed prairies I-V
Abstract has not been submitted
Authors
D. H. Johnson
[Book review] Railroad Postcards in the Age of Steam, by H. Roger Grant
Book review: Railroad Postcards in the Age of Steam. H. Roger Grant. University Of Iowa Press. 1994. 217 pages. ISBN: 0877454655.
Authors
D. H. Johnson
Point counts of birds: what are we estimating?
Point counts of birds are made for many reasons, including estimating local densities, determining population trends, assessing habitat preferences, and exploiting the activities of recreational birdwatchers. Problems arise unless there is a clear understanding of what point counts mean in terms of actual populations of birds. Criteria for conducting point counts depend strongly on the purposes to
Authors
D. H. Johnson
[Book review] Conservation and Management of Neotropical Migrant Landbirds in the Northern Rockies and Great Plains, by David S. Dobkin, R. Gerald Wright, and Stephen C. Bunting
Review of: Conservation and management of neotropical migrant landbirds in the Northern Rockies and Great Plains. Northwest Naturalist Books. David S. Dobkin, R. Gerald Wright, Stephen C. Bunting. University of Idaho Press, 1994. ISBN: 0893011681, 9780893011680.
Authors
D. H. Johnson
Statistical sirens: The allure of nonparametrics
Although nonparametric statistical methods have a role to play in the analysis of data, often their virtues are overstated and their deficiencies overlooked. A recent Special Feature in Ecology advocated nonparametric methods because of an erroneously stated advantage that they require no assumptions regarding the distribution underlying the observations. The present paper points out some often—ig
Authors
Douglas H. Johnson
Bird censuses 126-131: Kentucky bluegrass prairie and mixed prairies I-V
Abstract has not been submitted
Authors
D. H. Johnson, M.D. Schwartz
Wildlife habitat management on the northern prairie landscape
The northern prairie landscape has changed dramatically within the past century as a result of settlement by Europeans. Natural ecosystems have been disrupted and wildlife populations greatly altered. Natural resource agencies control only limited areas within the landscape, which they cannot manage independently of privately owned lands. Wildlife managers need first to set quantifiable objectives
Authors
Douglas H. Johnson, Susan D. Haseltine, Lewis M. Cowardin
Science and Products
Filter Total Items: 311
Conservation Reserve Program and migratory birds in the northern Great Plains
U.S. Department of Agriculture programs have mediated supply and demand of commodities and maintained the agricultural industry, but several programs have also offered various kinds of conservation benefits. The 1985 Food Security Act (Farm Bill) featured the Conservation Reserve Program (CRP), which paid farmers to plant perennial cover on highly erodible lands and to leave this land intact for a
Authors
Douglas H. Johnson, Rolf R. Koford
Contributions of the Conservation Reserve Program to populations of breeding birds in North Dakota
Previous studies have shown that habitat provided by the Conservation Reserve Program (CRP), a feature of the 1985 farm bill, is used by many birds. The present study quantitatively assesses the importance of the CRP by estimating changes in breeding-bird populations of North Dakota projected if CRP land would revert to cultivation. Of 18 species that were common in CRP or crop fields or both, 12
Authors
D. H. Johnson, L.D. Igl
Using known populations of pronghorn to evaluate sampling plans and estimators
Although sampling plans and estimators of abundance have good theoretical properties, their performance in real situations is rarely assessed because true population sizes are unknown. We evaluated widely used sampling plans and estimators of population size on 3 known clustered distributions of pronghorn (Antilocapra americana). Our criteria were accuracy of the estimate, coverage of 95% confiden
Authors
K.M. Kraft, D. H. Johnson, J.M. Samuelson, S.H. Allen
Bird censuses 123-128: Kentucky bluegrass prairie and mixed prairies I-V
Abstract has not been submitted
Authors
D. H. Johnson
[Book review] Railroad Postcards in the Age of Steam, by H. Roger Grant
Book review: Railroad Postcards in the Age of Steam. H. Roger Grant. University Of Iowa Press. 1994. 217 pages. ISBN: 0877454655.
Authors
D. H. Johnson
Point counts of birds: what are we estimating?
Point counts of birds are made for many reasons, including estimating local densities, determining population trends, assessing habitat preferences, and exploiting the activities of recreational birdwatchers. Problems arise unless there is a clear understanding of what point counts mean in terms of actual populations of birds. Criteria for conducting point counts depend strongly on the purposes to
Authors
D. H. Johnson
[Book review] Conservation and Management of Neotropical Migrant Landbirds in the Northern Rockies and Great Plains, by David S. Dobkin, R. Gerald Wright, and Stephen C. Bunting
Review of: Conservation and management of neotropical migrant landbirds in the Northern Rockies and Great Plains. Northwest Naturalist Books. David S. Dobkin, R. Gerald Wright, Stephen C. Bunting. University of Idaho Press, 1994. ISBN: 0893011681, 9780893011680.
Authors
D. H. Johnson
Statistical sirens: The allure of nonparametrics
Although nonparametric statistical methods have a role to play in the analysis of data, often their virtues are overstated and their deficiencies overlooked. A recent Special Feature in Ecology advocated nonparametric methods because of an erroneously stated advantage that they require no assumptions regarding the distribution underlying the observations. The present paper points out some often—ig
Authors
Douglas H. Johnson
Bird censuses 126-131: Kentucky bluegrass prairie and mixed prairies I-V
Abstract has not been submitted
Authors
D. H. Johnson, M.D. Schwartz
Wildlife habitat management on the northern prairie landscape
The northern prairie landscape has changed dramatically within the past century as a result of settlement by Europeans. Natural ecosystems have been disrupted and wildlife populations greatly altered. Natural resource agencies control only limited areas within the landscape, which they cannot manage independently of privately owned lands. Wildlife managers need first to set quantifiable objectives
Authors
Douglas H. Johnson, Susan D. Haseltine, Lewis M. Cowardin