Brenda Ballachey, Ph.D.
Population status and indices of population condition; population, physiological and ecological effects of oil exposure on marine mammals and coastal ecosystems; environmental toxicology, physiology and genetics of marine mammals.
Professional Experience
2016 - Present Research Physiologist Emeritus, USGS, Alaska Science Center, Anchorage, Alaska
1990 - 2016 Research Physiologist, USGS, Alaska Science Center, Anchorage, Alaska
1989 - 1990 Biologist, USGS, Alaska Science Center, Anchorage, Alaska
1987 - 1989 Staff Officer, Board on Agriculture, National Research Council, Washington, D.C.
1986 - 1987 Research Associate, Department of Chemistry, South Dakota State University, Brookings, South Dakota
1985 - 1985 Instructor, Department of Animal Science, Oregon State University, Corvallis, Oregon
1981 - 1985 Graduate Research Assistant, Department of Animal Science, Oregon State University, Corvallis, Oregon
1977 - 1980 Graduate Research Assistant, Department of Animal Science, Colorado State University, Ft. Collins, Colorado
Education and Certifications
Ph.D. 1985 Oregon State University, Corvallis, OR Animal Breeding and Genetics
M.S. 1980 Colorado State University, Ft. Collins, CO Animal Sciences
B.S. 1974 Colorado State University, Ft. Collins, CO Animal Science
Affiliations and Memberships*
Society for Marine Mammalogy
The Wildlife Society
Society of Environmental Toxicology and Chemistry
Science and Products
Hematology and clinical chemistry of sea otters vaptured in Prince William Sound, Alaska following the Exxon Valdez Oil Spill
Overview of studies to determine injury caused by the Exxon Valdez Oil Spill to marine mammals
Monitoring the status of wild sea otter populations: field studies and techniques
Mitochondrial-DNA variation among subspecies and populations of sea otters (Enhydra lutris)
Clinical and clinical laboratory correlates in sea otters dying unexpectedly in rehabilitation centers following the Exxon Valdez oil spill
Release strategies for rehabilitated sea otters
Hydrocarbon residues in sea otter tissues
Pathology of sea otters
An overview of sea otter studies
Implementation of biomarker-based studies
Histopathologic lesions in sea otters exposed to crude oil
Science and Products
- Data
- Publications
Filter Total Items: 71
Hematology and clinical chemistry of sea otters vaptured in Prince William Sound, Alaska following the Exxon Valdez Oil Spill
Hematologic and serum chemical analyses were performed on sea otter blood samples collected from 31 adult males, 63 adult females, and 42 pups captured in western Prince William Sound (oiled area), and 12 adult males, 40 adult females, and 15 pups captured in eastern Prince William Sound (unoiled area) in 1989 and 1990. Hematologic differences between eastern and western adult males were minimal.AuthorsA.H. Rebar, Brenda E. Ballachey, D.L. Bruden, Kimberly A. KloeckerOverview of studies to determine injury caused by the Exxon Valdez Oil Spill to marine mammals
Marine mammal damage assessment studies after the Exxon Valdez oil spill concentrated on sea otters, harbor seals, Steller sea lions, killer whales, and humpback whales. Sea otter and harbor seals were the most affected marine mammal; it was estimated that several thousand otters and several hundred harbor seals died within months of the spill. Steller sea lion, harbor seal, aAuthorsThomas R. Loughlin, Brenda E. Ballachey, B.A. WrightMonitoring the status of wild sea otter populations: field studies and techniques
No abstract available.AuthorsJames L. Bodkin, Brenda E. BallacheyMitochondrial-DNA variation among subspecies and populations of sea otters (Enhydra lutris)
We used restriction-enzyme analysis of polymerase-chain reaction-amplified, mitochondrial DNA (mtDNA) to assess genetic differentiation of subspecies and populations of sea otters, Enhydra lutris, throughout the range of the species. There were several haplotypes of mtDNA in each subspecies and geographically separate populations. MtDNA sequence divergence of haplotypes of sea otters was 0.0004–0.AuthorsMatthew A. Cronin, James L. Bodkin, Brenda E. Ballachey, James A. Estes, John C. PattonClinical and clinical laboratory correlates in sea otters dying unexpectedly in rehabilitation centers following the Exxon Valdez oil spill
Following the Exxon Valdez oil spill, 347 oiled sea otters (Enhydra lutris) were treated in rehabilitation centers. Of these, 116 died, 94 within 10 days of presentation. Clinical records of 21 otters dying during the first 10 days of rehabilitation were reviewed to define the laboratory abnormalities and clinical syndromes associated with these unexpected deaths. The most common terminal syndromeAuthorsA.H. Rebar, T.P. Lipscomb, R.K. Harris, Brenda E. BallacheyRelease strategies for rehabilitated sea otters
According to the U.S. Fish and Wildlife Services’ (USFWS) Response Plan for sea otters (USFWS, in preparation), in the event of an oil spill, the decision to release sea otters from rehabilitation centers following treatment will be linked to the decision on whether to capture sea otters for treatment. Assuming a scenario similar to the Exxon Valdez oil spill (EVOS), once the decision to capture sAuthorsAnthony R. DeGange, Brenda E. Ballachey, Keith BayhaHydrocarbon residues in sea otter tissues
On 24 March 1989, the T/V Exxon Valdez ran aground in Prince William Sound (PWS). eventually releasing 11 million gallons of Prudhoe Bay crude oil. The subsequent oil slick extended from PWS southwest along the Kenai Peninsula, past Kodiak Island to the Alaska Peninsula (Galt and Payton 1990). The spill encompassed extensive areas of sea otter (Enhydra lutris) habitat. Estimates of sea otter mortaAuthorsDaniel M. Mulcahy, Brenda E. BallacheyPathology of sea otters
In the months following the Exxon Valdez oil spill (EVOS), 994 sea otters (Enhydra lutris) from oil-spill-affected areas died (Doroff et al. 1993). Carcasses collected from these areas and otters that died in rehabilitation centers are included in this number. The actual number that died was probably much greater.Within days of the spill, the Exxon Company (USA) funded an effort to rehabilitate oiAuthorsT.P. Lipscomb, Richard K. Harris, A.H. Rebar, Brenda E. Ballachey, Romona J. HaeblerAn overview of sea otter studies
The Exxron Valdez oil spill (EVOS) on 24 March 1989 threatened extensive areas of prime sea otter (Enhydra lutris) habitat along the coasts of south-central Alaska. The spill occurred in northeastern Prince William Sound (PWS), and oil moved rapidly south and west through PWS into the Gulf of Alaska. Much of the coastline of western PWS was heavily oiled, and the slick eventually spread as far souAuthorsBrenda E. Ballachey, James L. Bodkin, Anthony R. DeGangeImplementation of biomarker-based studies
Biomarkers may be used to determine chemical exposure and effects in several important ways. These include (1) evaluation of new agricultural or industrial chemicals for effects, (2) screening of municipal or industrial effluents, (3) determining the geographic distribution of chemical effects in the environment and their changes over time, (4) determining the identity and source of chemical polluAuthorsJohn J. Stegeman, Brenda E. Ballachey, J. Bickham, B. Höcker, S. Kennedy, H. Thompson, A.D. VethaakHistopathologic lesions in sea otters exposed to crude oil
Following the Exxon Valdez oil spill in Prince William Sound, Alaska, sea otters (Enhydra lutris) that appeared to be contaminated with oil, that were in danger of becoming contaminated, or that were behaving abnormally were captured and taken to rehabilitation centers. Exposure to oil was assessed by visual examination when otters arrived at the centers. Degree of oil exposure was graded accordinAuthorsT.P. Lipscomb, R.K. Harris, R.B. Moeller, J.M. Pletcher, R.J. Haebler, Brenda E. Ballachey
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government