Robert E Anthony
Robert Anthony is a Research Geophysicist in the Earthquake Hazards Program.
Science and Products
Filter Total Items: 61
Sources of organochlorine contaminants and mercury in seabirds from the Aleutian archipelago of Alaska: Inferences from spatial and trophic variation Sources of organochlorine contaminants and mercury in seabirds from the Aleutian archipelago of Alaska: Inferences from spatial and trophic variation
Persistent organochlorine compounds and mercury (Hg) have been detected in numerous coastal organisms of the Aleutian archipelago of Alaska, yet sources of these contaminants are unclear. We collected glaucous-winged gulls, northern fulmars, and tufted puffins along a natural longitudinal gradient across the western and central Aleutian Islands (Buldir, Kiska, Amchitka, Adak), and an...
Authors
Mark A. Ricca, A. Keith Miles, Robert G. Anthony
Modeling of site occupancy dynamics for northern spotted owls, with emphasis on the effects of barred owls Modeling of site occupancy dynamics for northern spotted owls, with emphasis on the effects of barred owls
Northern spotted owls (Strix occidentalis caurina) have been studied intensively since their listing as a threatened species by the U.S. Fish and Wildlife Service in 1990. Studies of spotted owl site occupancy have used various binary response measures, but most of these studies have made the assumption that detectability is perfect, or at least high and not variable. Further, previous...
Authors
Gail S. Olson, Robert G. Anthony, Eric D. Forsman, Steven H. Ackers, Peter J. Loschl, Janice A. Reid, Katie M. Dugger, Elizabeth M. Glenn, William J. Ripple
The relationship between habitat characteristics and demographic performance of northern spotted owls in southern Oregon The relationship between habitat characteristics and demographic performance of northern spotted owls in southern Oregon
We used data from Northern Spotted Owl (Strix occidentalis caurina) territories to model the effects of habitat (particularly intermediate-aged forest stand types), climate, and nonhabitat covariates (i.e., age, sex) on owl reproductive rate and apparent survival in southwestern Oregon. Our best model for reproductive rate included an interaction between a cyclic, annual time trend and...
Authors
Katie M. Dugger, Frank Wagner, Robert G. Anthony, Gail S. Olson
Bald Eagles consume Emperor Geese during late-winter in the Aleutian Archipelago Bald Eagles consume Emperor Geese during late-winter in the Aleutian Archipelago
Emperor Geese (Chen canagica) are a species of concern because their population has declined rapidly since the mid-1960s and continues to remain below management objectives (Petersen et al. 1994). Emperor Geese are restricted primarily to Alaska and exhibit an east-west migration pattern, whereby most birds begin breeding on the Yukon-Kuskokwim Delta by mid-May, stage on the Alaska...
Authors
Mark A. Ricca, Robert G. Anthony, Jeffrey C. Williams
Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon
Northern spotted owls (Strix occidentalis caurina) are known to be associated with late-successional forests in the Pacific Northwest of the United States, but the effects of habitat on their demographic performance are relatively unknown. We developed statistical models relating owl survival and productivity to forest cover types within the Roseburg Study Area in the Oregon Coast Range...
Authors
Gail S. Olson, Elizabeth M. Glenn, Robert G. Anthony, Eric D. Forsman, Janice A. Reid, Peter J. Loschl, William J. Ripple
Survival of Columbian white-tailed deer in western Oregon Survival of Columbian white-tailed deer in western Oregon
Columbian white-tailed deer (Odocoileus virginianus leucurus; CWTD) are an endangered subspecies on which little demographic information exists. We determined survival rates and causes of mortality for 64 radiocol- lared adults from 1996 to 1998, and for 63 radiocollared neonatal fawns during the summer and fall months of 1996-2001 in Douglas County, Oregon, USA. Annual adult survival...
Authors
Mark A. Ricca, Robert G. Anthony, Dewaine H. Jackson, Scott A. Wolfe
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 61
Sources of organochlorine contaminants and mercury in seabirds from the Aleutian archipelago of Alaska: Inferences from spatial and trophic variation Sources of organochlorine contaminants and mercury in seabirds from the Aleutian archipelago of Alaska: Inferences from spatial and trophic variation
Persistent organochlorine compounds and mercury (Hg) have been detected in numerous coastal organisms of the Aleutian archipelago of Alaska, yet sources of these contaminants are unclear. We collected glaucous-winged gulls, northern fulmars, and tufted puffins along a natural longitudinal gradient across the western and central Aleutian Islands (Buldir, Kiska, Amchitka, Adak), and an...
Authors
Mark A. Ricca, A. Keith Miles, Robert G. Anthony
Modeling of site occupancy dynamics for northern spotted owls, with emphasis on the effects of barred owls Modeling of site occupancy dynamics for northern spotted owls, with emphasis on the effects of barred owls
Northern spotted owls (Strix occidentalis caurina) have been studied intensively since their listing as a threatened species by the U.S. Fish and Wildlife Service in 1990. Studies of spotted owl site occupancy have used various binary response measures, but most of these studies have made the assumption that detectability is perfect, or at least high and not variable. Further, previous...
Authors
Gail S. Olson, Robert G. Anthony, Eric D. Forsman, Steven H. Ackers, Peter J. Loschl, Janice A. Reid, Katie M. Dugger, Elizabeth M. Glenn, William J. Ripple
The relationship between habitat characteristics and demographic performance of northern spotted owls in southern Oregon The relationship between habitat characteristics and demographic performance of northern spotted owls in southern Oregon
We used data from Northern Spotted Owl (Strix occidentalis caurina) territories to model the effects of habitat (particularly intermediate-aged forest stand types), climate, and nonhabitat covariates (i.e., age, sex) on owl reproductive rate and apparent survival in southwestern Oregon. Our best model for reproductive rate included an interaction between a cyclic, annual time trend and...
Authors
Katie M. Dugger, Frank Wagner, Robert G. Anthony, Gail S. Olson
Bald Eagles consume Emperor Geese during late-winter in the Aleutian Archipelago Bald Eagles consume Emperor Geese during late-winter in the Aleutian Archipelago
Emperor Geese (Chen canagica) are a species of concern because their population has declined rapidly since the mid-1960s and continues to remain below management objectives (Petersen et al. 1994). Emperor Geese are restricted primarily to Alaska and exhibit an east-west migration pattern, whereby most birds begin breeding on the Yukon-Kuskokwim Delta by mid-May, stage on the Alaska...
Authors
Mark A. Ricca, Robert G. Anthony, Jeffrey C. Williams
Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon
Northern spotted owls (Strix occidentalis caurina) are known to be associated with late-successional forests in the Pacific Northwest of the United States, but the effects of habitat on their demographic performance are relatively unknown. We developed statistical models relating owl survival and productivity to forest cover types within the Roseburg Study Area in the Oregon Coast Range...
Authors
Gail S. Olson, Elizabeth M. Glenn, Robert G. Anthony, Eric D. Forsman, Janice A. Reid, Peter J. Loschl, William J. Ripple
Survival of Columbian white-tailed deer in western Oregon Survival of Columbian white-tailed deer in western Oregon
Columbian white-tailed deer (Odocoileus virginianus leucurus; CWTD) are an endangered subspecies on which little demographic information exists. We determined survival rates and causes of mortality for 64 radiocol- lared adults from 1996 to 1998, and for 63 radiocollared neonatal fawns during the summer and fall months of 1996-2001 in Douglas County, Oregon, USA. Annual adult survival...
Authors
Mark A. Ricca, Robert G. Anthony, Dewaine H. Jackson, Scott A. Wolfe
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.