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: 310
Tower counts
Counting towers provide an accurate, low-cost, low-maintenance, low-technology, and easily mobilized escapement estimation program compared to other methods (e.g., weirs, hydroacoustics, mark-recapture, and aerial surveys) (Thompson 1962; Siebel 1967; Cousens et al. 1982; Symons and Waldichuk 1984; Anderson 2000; Alaska Department of Fish and Game 2003). Counting tower data has been found to be co
Authors
Carol Ann Woody
Brown-headed cowbird, Molothrus ater, parasitism and abundance in the northern Great Plains
The Brown-headed Cowbird (Molothrus ater) reaches its highest abundance in the northern Great Plains, but much of our understanding of cowbird ecology and host-parasite interactions comes from areas outside of this region. We examine cowbird brood parasitism and densities during two studies of breeding birds in the northern Great Plains during 1990–2006. We found 2649 active nests of 75 species, i
Authors
L.D. Igl, D. H. Johnson
A review of the population estimation approach of the North American landbird conservation plan
As part of their development of a continental plan for monitoring landbirds (Rich et al. 2004), Partners in Flight (PIF) applied a new method to make preliminary estimates of population size for all 448 species of landbirds present in the continental United States and Canada (Table 1). Estimation of the global population size of North American landbirds was intended to (1) identify the degree of v
Authors
Wayne E. Thogmartin, Frank P. Howe, Frances C. James, Douglas H. Johnson, Eric T. Reed, John R. Sauer, Frank R. Thompson
Does body size affect a bird's sensitivity to patch size and landscape structure?
Larger birds are generally more strongly affected by habitat loss and fragmentation than are smaller ones because they require more resources and thus larger habitat patches. Consequently, conservation actions often favor the creation or protection of larger over smaller patches. However, in grassland systems the boundaries between a patch and the surrounding landscape, and thus the perceived size
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer
Conspecific attraction in a grassland bird, the Baird's Sparrow
Territorial songbirds generally use song to defend territories and attract mates, but conspecific song may also serve as a cue to attract other male songbirds to a breeding site. Although known to occur in some colonial and forest-associated species, only recently have investigators examined conspecific attraction in grassland species. We used a playback experiment to examine the possible role of
Authors
M.A. Ahlering, D. H. Johnson, John Faaborg
Patch size and landscape effects on density and nesting success of grassland birds
Current management recommendations for grassland birds in North America emphasize providing large patches of grassland habitat within landscapes that have few forest or shrubland areas. These Bird Conservation Areas are being proposed under the assumption that large patches of habitat in treeless landscapes will maintain viable populations of grassland birds. This assumption requires that patch si
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer, Therese M. Donovan, W. Daniel Svedarsky
Proximate and landscape factors influence grassland bird distributions
Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conserv
Authors
M.A. Cunningham, D. H. Johnson
A fresh look at the taxonomy of midcontinental sandhill cranes
The midcontinental population of sandhill crane (Grus canadensis) includes about 500,000 birds and provides valuable recreational crane-watching and hunting opportunities in Canada and the United States. It comprises three subspecies, one of which (G. c. rowani) was of uncertain taxonomic status and another of which (G. c. tabida) merited protection from excessive harvest due to its small populati
Authors
Douglas H. Johnson, Jane E. Austin, Jill A. Shaffer
A retrospective perspective: evaluating population changes by repeating historic bird surveys
Acquiring an accurate picture of the changes in bird populations often involves a tradeoff between the time and effort required to complete the surveys and the number of years spent surveying the bird populations. An alternative approach to long-term monitoring efforts is to collect current data and contrast those with data collected earlier in a similar fashion on the same study site(s). To evalu
Authors
Lawrence D. Igl, Douglas H. Johnson
What hypothesis tests are not: a response to Colegrave and Ruxton
No abstract available.
Authors
Douglas H. Johnson
Planning for bird conservation: a tale of two models
Planning for bird conservation has become increasingly reliant on remote sensing, geographical information systems, and, especially, models used to predict the occurrence of bird species as well as their density and demographics. We address the role of such tools by contrasting two models used in bird conservation. One, the Mallard ( Anas platyrhynchos) productivity model, is very detailed, mech
Authors
Douglas H. Johnson, Maiken Winter
Habitat and nesting of Le Conte's Sparrows in the northern tallgrass prairie
Little is known about the breeding biology of the Le Conte's Sparrow (Ammodramus leconteii), probably because of its secretive nature. We provide new information on several aspects of Le Conte's Sparrow breeding biology, including rates of nest parasitism by Brown-headed Cowbirds (Molothrus ater) and potential factors affecting breeding densities and nesting success of the species. Our study was c
Authors
Maiken Winter, Jill A. Shaffer, Douglas H. Johnson, Therese M. Donovan, W. Daniel Svedarsky, P.W. Jones, Betty R. Euliss
Science and Products
Filter Total Items: 310
Tower counts
Counting towers provide an accurate, low-cost, low-maintenance, low-technology, and easily mobilized escapement estimation program compared to other methods (e.g., weirs, hydroacoustics, mark-recapture, and aerial surveys) (Thompson 1962; Siebel 1967; Cousens et al. 1982; Symons and Waldichuk 1984; Anderson 2000; Alaska Department of Fish and Game 2003). Counting tower data has been found to be co
Authors
Carol Ann Woody
Brown-headed cowbird, Molothrus ater, parasitism and abundance in the northern Great Plains
The Brown-headed Cowbird (Molothrus ater) reaches its highest abundance in the northern Great Plains, but much of our understanding of cowbird ecology and host-parasite interactions comes from areas outside of this region. We examine cowbird brood parasitism and densities during two studies of breeding birds in the northern Great Plains during 1990–2006. We found 2649 active nests of 75 species, i
Authors
L.D. Igl, D. H. Johnson
A review of the population estimation approach of the North American landbird conservation plan
As part of their development of a continental plan for monitoring landbirds (Rich et al. 2004), Partners in Flight (PIF) applied a new method to make preliminary estimates of population size for all 448 species of landbirds present in the continental United States and Canada (Table 1). Estimation of the global population size of North American landbirds was intended to (1) identify the degree of v
Authors
Wayne E. Thogmartin, Frank P. Howe, Frances C. James, Douglas H. Johnson, Eric T. Reed, John R. Sauer, Frank R. Thompson
Does body size affect a bird's sensitivity to patch size and landscape structure?
Larger birds are generally more strongly affected by habitat loss and fragmentation than are smaller ones because they require more resources and thus larger habitat patches. Consequently, conservation actions often favor the creation or protection of larger over smaller patches. However, in grassland systems the boundaries between a patch and the surrounding landscape, and thus the perceived size
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer
Conspecific attraction in a grassland bird, the Baird's Sparrow
Territorial songbirds generally use song to defend territories and attract mates, but conspecific song may also serve as a cue to attract other male songbirds to a breeding site. Although known to occur in some colonial and forest-associated species, only recently have investigators examined conspecific attraction in grassland species. We used a playback experiment to examine the possible role of
Authors
M.A. Ahlering, D. H. Johnson, John Faaborg
Patch size and landscape effects on density and nesting success of grassland birds
Current management recommendations for grassland birds in North America emphasize providing large patches of grassland habitat within landscapes that have few forest or shrubland areas. These Bird Conservation Areas are being proposed under the assumption that large patches of habitat in treeless landscapes will maintain viable populations of grassland birds. This assumption requires that patch si
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer, Therese M. Donovan, W. Daniel Svedarsky
Proximate and landscape factors influence grassland bird distributions
Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conserv
Authors
M.A. Cunningham, D. H. Johnson
A fresh look at the taxonomy of midcontinental sandhill cranes
The midcontinental population of sandhill crane (Grus canadensis) includes about 500,000 birds and provides valuable recreational crane-watching and hunting opportunities in Canada and the United States. It comprises three subspecies, one of which (G. c. rowani) was of uncertain taxonomic status and another of which (G. c. tabida) merited protection from excessive harvest due to its small populati
Authors
Douglas H. Johnson, Jane E. Austin, Jill A. Shaffer
A retrospective perspective: evaluating population changes by repeating historic bird surveys
Acquiring an accurate picture of the changes in bird populations often involves a tradeoff between the time and effort required to complete the surveys and the number of years spent surveying the bird populations. An alternative approach to long-term monitoring efforts is to collect current data and contrast those with data collected earlier in a similar fashion on the same study site(s). To evalu
Authors
Lawrence D. Igl, Douglas H. Johnson
What hypothesis tests are not: a response to Colegrave and Ruxton
No abstract available.
Authors
Douglas H. Johnson
Planning for bird conservation: a tale of two models
Planning for bird conservation has become increasingly reliant on remote sensing, geographical information systems, and, especially, models used to predict the occurrence of bird species as well as their density and demographics. We address the role of such tools by contrasting two models used in bird conservation. One, the Mallard ( Anas platyrhynchos) productivity model, is very detailed, mech
Authors
Douglas H. Johnson, Maiken Winter
Habitat and nesting of Le Conte's Sparrows in the northern tallgrass prairie
Little is known about the breeding biology of the Le Conte's Sparrow (Ammodramus leconteii), probably because of its secretive nature. We provide new information on several aspects of Le Conte's Sparrow breeding biology, including rates of nest parasitism by Brown-headed Cowbirds (Molothrus ater) and potential factors affecting breeding densities and nesting success of the species. Our study was c
Authors
Maiken Winter, Jill A. Shaffer, Douglas H. Johnson, Therese M. Donovan, W. Daniel Svedarsky, P.W. Jones, Betty R. Euliss