Brenda Ballachey, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 73
Sea otter (Enhydra lutris) perspective: Part A. Sea otter population status and the process of recovery from the 1989 Exxon Valdez oil spill Sea otter (Enhydra lutris) perspective: Part A. Sea otter population status and the process of recovery from the 1989 Exxon Valdez oil spill
Sea otter (Enhydra lutris) populations were severely affected by the 1989 Exxon Valdez oil spill in western Prince William Sound, AK, and had not fully recovered by 2000. Here we present results of population surveys and incorporate findings from related studies to identify current population status and factors affecting recovery. Between 1993 and 2000, the number of sea otters in the...
Authors
James L. Bodkin, Brenda E. Ballachey, Thomas A. Dean, Allan K. Fukuyama, Stephen C. Jewett, Lyman L. McDonald, Daniel H. Monson, Charles E. O’Clair, Glenn R. VanBlaricom
Chemical anesthesia of Northern sea otters (Enhydra lutris): Results of past field studies Chemical anesthesia of Northern sea otters (Enhydra lutris): Results of past field studies
Between 1987 and 1997, we chemically immobilized 597 wild sea otters (Enhydra lutris) in Alaska for the collection of biological samples or for surgical instrumentation. One drug-related sea otter fatality occurred during this time. Fentanyl in combination with diazepam produced consistent, smooth inductions with minimal need for supplemental anesthetics during procedures lasting 30-40...
Authors
Daniel H. Monson, C. McCormick, Brenda E. Ballachey
Marine predator surveys in Glacier Bay National Park and Preserve Marine predator surveys in Glacier Bay National Park and Preserve
No abstract available.
Authors
James L. Bodkin, Kimberly A. Kloecker, H.A. Coletti, George G. Esslinger, Daniel H. Monson, Brenda E. Ballachey
Long-term impacts of the Exxon Valdez oil spill on sea otters, assessed through age-dependent mortality patterns Long-term impacts of the Exxon Valdez oil spill on sea otters, assessed through age-dependent mortality patterns
We use age distributions of sea otters (Enhydra lutris) found dead on beaches of western Prince William Sound, Alaska, between 1976 and 1998 in conjunction with time-varying demographic models to test for lingering effects from the 1989 Exxon Valdez oil spill. Our results show that sea otters in this area had decreased survival rates in the years following the spill and that the effects...
Authors
Daniel H. Monson, Daniel F. Doak, Brenda E. Ballachey, Aaron H. Johnson, James L. Bodkin
Population demographics and genetic diversity in remnant and translocated populations of sea otters Population demographics and genetic diversity in remnant and translocated populations of sea otters
The effects of small population size on genetic diversity and subsequent population recovery are theoretically predicted, but few empirical data are available to describe those relations. We use data from four remnant and three translocated sea otter ( Enhydra lutris) populations to examine relations among magnitude and duration of minimum population size, population growth rates, and...
Authors
James L. Bodkin, Brenda E. Ballachey, M. A. Cronin, K.T. Scribner
Integrating ecosystem studies: A Bayesian comparison of hypotheses Integrating ecosystem studies: A Bayesian comparison of hypotheses
Ecosystem studies are difficult to interpret because of the complexity and number of pathways that may affect a phenomenon of interest. It is not possible to study all aspects of a problem; thus subjective judgment is required to weigh what has been observed in the context of components that were not studied but may have been important. This subjective judgment is usually a poorly...
Authors
Milo D. Adkison, Brenda E. Ballachey, James L. Bodkin, Leslie E. Holland-Bartels
Science and Products
Filter Total Items: 73
Sea otter (Enhydra lutris) perspective: Part A. Sea otter population status and the process of recovery from the 1989 Exxon Valdez oil spill Sea otter (Enhydra lutris) perspective: Part A. Sea otter population status and the process of recovery from the 1989 Exxon Valdez oil spill
Sea otter (Enhydra lutris) populations were severely affected by the 1989 Exxon Valdez oil spill in western Prince William Sound, AK, and had not fully recovered by 2000. Here we present results of population surveys and incorporate findings from related studies to identify current population status and factors affecting recovery. Between 1993 and 2000, the number of sea otters in the...
Authors
James L. Bodkin, Brenda E. Ballachey, Thomas A. Dean, Allan K. Fukuyama, Stephen C. Jewett, Lyman L. McDonald, Daniel H. Monson, Charles E. O’Clair, Glenn R. VanBlaricom
Chemical anesthesia of Northern sea otters (Enhydra lutris): Results of past field studies Chemical anesthesia of Northern sea otters (Enhydra lutris): Results of past field studies
Between 1987 and 1997, we chemically immobilized 597 wild sea otters (Enhydra lutris) in Alaska for the collection of biological samples or for surgical instrumentation. One drug-related sea otter fatality occurred during this time. Fentanyl in combination with diazepam produced consistent, smooth inductions with minimal need for supplemental anesthetics during procedures lasting 30-40...
Authors
Daniel H. Monson, C. McCormick, Brenda E. Ballachey
Marine predator surveys in Glacier Bay National Park and Preserve Marine predator surveys in Glacier Bay National Park and Preserve
No abstract available.
Authors
James L. Bodkin, Kimberly A. Kloecker, H.A. Coletti, George G. Esslinger, Daniel H. Monson, Brenda E. Ballachey
Long-term impacts of the Exxon Valdez oil spill on sea otters, assessed through age-dependent mortality patterns Long-term impacts of the Exxon Valdez oil spill on sea otters, assessed through age-dependent mortality patterns
We use age distributions of sea otters (Enhydra lutris) found dead on beaches of western Prince William Sound, Alaska, between 1976 and 1998 in conjunction with time-varying demographic models to test for lingering effects from the 1989 Exxon Valdez oil spill. Our results show that sea otters in this area had decreased survival rates in the years following the spill and that the effects...
Authors
Daniel H. Monson, Daniel F. Doak, Brenda E. Ballachey, Aaron H. Johnson, James L. Bodkin
Population demographics and genetic diversity in remnant and translocated populations of sea otters Population demographics and genetic diversity in remnant and translocated populations of sea otters
The effects of small population size on genetic diversity and subsequent population recovery are theoretically predicted, but few empirical data are available to describe those relations. We use data from four remnant and three translocated sea otter ( Enhydra lutris) populations to examine relations among magnitude and duration of minimum population size, population growth rates, and...
Authors
James L. Bodkin, Brenda E. Ballachey, M. A. Cronin, K.T. Scribner
Integrating ecosystem studies: A Bayesian comparison of hypotheses Integrating ecosystem studies: A Bayesian comparison of hypotheses
Ecosystem studies are difficult to interpret because of the complexity and number of pathways that may affect a phenomenon of interest. It is not possible to study all aspects of a problem; thus subjective judgment is required to weigh what has been observed in the context of components that were not studied but may have been important. This subjective judgment is usually a poorly...
Authors
Milo D. Adkison, Brenda E. Ballachey, James L. Bodkin, Leslie E. Holland-Bartels
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