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
Variability in vegetation effects on density and nesting success of grassland birds
The structure of vegetation in grassland systems, unlike that in forest systems, varies dramatically among years on the same sites, and among regions with similar vegetation. The role of this variation in vegetation structure on bird density and nesting success of grassland birds is poorly understood, primarily because few studies have included sufficiently large temporal and spatial scales to cap
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer
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
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
Markov Chain Monte Carlo estimation of species distributions: A case study of the swift fox in western Kansas
Accurate maps of species distributions are essential tools for wildlife research and conservation. Unfortunately, biologists often are forced to rely on maps derived from observed occurrences recorded opportunistically during observation periods of variable length. Spurious inferences are likely to result because such maps are profoundly affected by the duration and intensity of observation and by
Authors
Glen A. Sargeant, Marsha A. Sovada, Christiane C. Slivinski, Douglas H. Johnson
Grassland bird use of Conservation Reserve Program fields in the Great Plains
An enormous area in the Great Plains is currently enrolled in the Conservation Reserve Program (CRP): 19.5 million acres (nearly 8 million ha) in Montana, North Dakota, South Dakota, Wyoming, Nebraska, Colorado, Kansas, Oklahoma, and Texas. This change in land use from cropland to grassland since 1985 has markedly influenced grassland bird populations. Many, but certainly not all, grassland specie
Authors
Douglas H. Johnson
Effects of distance from cattle water developments on grassland birds
Many North American grassland bird populations appear to be declining, which may be due to changes in grazing regimes on their breeding areas. Establishment of water developments and confining cattle (Bos taurus L.) to small pastures often minimizes spatial heterogeneity of cattle forage consumption, which may lead to uniformity in vegetative structure. This increased uniformity may provide suitab
Authors
A.L. Fontaine, P.L. Kennedy, D. H. Johnson
Nesting biology of three grassland passerines in the northern tallgrass prairie
Basic nesting information on grassland passerines is needed for improving grassland bird management. Among the information needs are (1) the suitability of nesting habitat, (2) periods during the breeding season in which birds are most vulnerable to disturbances, and (3) how to fit grasslands into a prioritization scheme for conservation. Comparisons of nesting parameters among grassland species w
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer, W. Daniel Svedarsky
Comparison of detection rates of breeding marsh birds in passive and playback surveys at Lacreek National Wildlife Refuge, South Dakota
We compared detection rates of passive and playback breeding bird survey techniques on elusive marsh birds - Pied-billed Grebe (Podilymbus podiceps), American Bittern (Botaurus lentiginosus), Least Bittern (Ixobrychus exilis), Virginia Rail (Rallus limicola), and Sora (Porzana carolina) - during a two-year study at Lacreek National Wildlife Refuge, in southwestern South Dakota. We conducted 151 pa
Authors
T. Allen, S. L. Finkbeiner, Douglas H. Johnson
Effects of distance from cattle water developments on grassland birds
Many North American grassland bird populations appear to be declining, which may be due to changes in grazing regimes on their breeding areas. Establishment of water developments and confining cattle (Bos taurus L.) to small pastures often minimizes spatial heterogeneity of cattle forage consumption, which may lead to uniformity in vegetative structure. This increased uniformity may provide suitab
Authors
A.L. Fontaine, P.L. Kennedy, D. H. Johnson
Guidelines for finding nests of passerine birds in tallgrass prairie
The productivity of birds is one of the most critical components of their natural history affected by habitat quality. Birds might occur at high densities in a given habitat patch but have low nesting success. Such "population sinks" would not be detected if observers relied solely on estimates of bird density. Therefore, it is essential to monitor nests and determine their outcomes. Although inte
Authors
Maiken Winter, Shawn E. Hawks, Jill A. Shaffer, Douglas H. Johnson
Brown-headed cowbirds in grasslands: Their habitats, hosts, and response to management
The brown-headed cowbird (Molothrus ater) is an obligate brood parasite whose numbers have increased in recent decades to the potential detriment of the species that they parasitize. Thus, most management efforts focus on discouraging brown-headed cowbird parasitism or controlling brown-headed cowbird populations. Keys to discouraging cowbird parasitism or controlling populations of brown-headed c
Authors
Jill A. Shaffer, Christopher M. Goldade, Meghan F. Dinkins, Douglas H. Johnson, Lawrence D. Igl, Betty R. Euliss
Grassland bird communities and environmental health: the role of landscape features
No abstract available.
Authors
D. H. Johnson, S.F. Browder, M. Winter
Science and Products
Filter Total Items: 310
Variability in vegetation effects on density and nesting success of grassland birds
The structure of vegetation in grassland systems, unlike that in forest systems, varies dramatically among years on the same sites, and among regions with similar vegetation. The role of this variation in vegetation structure on bird density and nesting success of grassland birds is poorly understood, primarily because few studies have included sufficiently large temporal and spatial scales to cap
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer
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
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
Markov Chain Monte Carlo estimation of species distributions: A case study of the swift fox in western Kansas
Accurate maps of species distributions are essential tools for wildlife research and conservation. Unfortunately, biologists often are forced to rely on maps derived from observed occurrences recorded opportunistically during observation periods of variable length. Spurious inferences are likely to result because such maps are profoundly affected by the duration and intensity of observation and by
Authors
Glen A. Sargeant, Marsha A. Sovada, Christiane C. Slivinski, Douglas H. Johnson
Grassland bird use of Conservation Reserve Program fields in the Great Plains
An enormous area in the Great Plains is currently enrolled in the Conservation Reserve Program (CRP): 19.5 million acres (nearly 8 million ha) in Montana, North Dakota, South Dakota, Wyoming, Nebraska, Colorado, Kansas, Oklahoma, and Texas. This change in land use from cropland to grassland since 1985 has markedly influenced grassland bird populations. Many, but certainly not all, grassland specie
Authors
Douglas H. Johnson
Effects of distance from cattle water developments on grassland birds
Many North American grassland bird populations appear to be declining, which may be due to changes in grazing regimes on their breeding areas. Establishment of water developments and confining cattle (Bos taurus L.) to small pastures often minimizes spatial heterogeneity of cattle forage consumption, which may lead to uniformity in vegetative structure. This increased uniformity may provide suitab
Authors
A.L. Fontaine, P.L. Kennedy, D. H. Johnson
Nesting biology of three grassland passerines in the northern tallgrass prairie
Basic nesting information on grassland passerines is needed for improving grassland bird management. Among the information needs are (1) the suitability of nesting habitat, (2) periods during the breeding season in which birds are most vulnerable to disturbances, and (3) how to fit grasslands into a prioritization scheme for conservation. Comparisons of nesting parameters among grassland species w
Authors
Maiken Winter, Douglas H. Johnson, Jill A. Shaffer, W. Daniel Svedarsky
Comparison of detection rates of breeding marsh birds in passive and playback surveys at Lacreek National Wildlife Refuge, South Dakota
We compared detection rates of passive and playback breeding bird survey techniques on elusive marsh birds - Pied-billed Grebe (Podilymbus podiceps), American Bittern (Botaurus lentiginosus), Least Bittern (Ixobrychus exilis), Virginia Rail (Rallus limicola), and Sora (Porzana carolina) - during a two-year study at Lacreek National Wildlife Refuge, in southwestern South Dakota. We conducted 151 pa
Authors
T. Allen, S. L. Finkbeiner, Douglas H. Johnson
Effects of distance from cattle water developments on grassland birds
Many North American grassland bird populations appear to be declining, which may be due to changes in grazing regimes on their breeding areas. Establishment of water developments and confining cattle (Bos taurus L.) to small pastures often minimizes spatial heterogeneity of cattle forage consumption, which may lead to uniformity in vegetative structure. This increased uniformity may provide suitab
Authors
A.L. Fontaine, P.L. Kennedy, D. H. Johnson
Guidelines for finding nests of passerine birds in tallgrass prairie
The productivity of birds is one of the most critical components of their natural history affected by habitat quality. Birds might occur at high densities in a given habitat patch but have low nesting success. Such "population sinks" would not be detected if observers relied solely on estimates of bird density. Therefore, it is essential to monitor nests and determine their outcomes. Although inte
Authors
Maiken Winter, Shawn E. Hawks, Jill A. Shaffer, Douglas H. Johnson
Brown-headed cowbirds in grasslands: Their habitats, hosts, and response to management
The brown-headed cowbird (Molothrus ater) is an obligate brood parasite whose numbers have increased in recent decades to the potential detriment of the species that they parasitize. Thus, most management efforts focus on discouraging brown-headed cowbird parasitism or controlling brown-headed cowbird populations. Keys to discouraging cowbird parasitism or controlling populations of brown-headed c
Authors
Jill A. Shaffer, Christopher M. Goldade, Meghan F. Dinkins, Douglas H. Johnson, Lawrence D. Igl, Betty R. Euliss
Grassland bird communities and environmental health: the role of landscape features
No abstract available.
Authors
D. H. Johnson, S.F. Browder, M. Winter