Brenda Ballachey, Ph.D. (Former Employee)
Science and Products
Intertidal Temperature Data from Kachemak Bay, Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
These data are part of the Gulf Watch Alaska (GWA) long-term monitoring program. This dataset consists of date, time, and temperature measurements from intertidal rocky sampling sites, including predicted tide height at the time of the reading, which is used to distinguish air from water temperature readings. The data are provided as comma separated values (.csv) files derived from data downloaded
Intertidal Mussel (Mytilus) Data from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
These data are part of the Gulf Watch Alaska (GWA) long-term monitoring program and describe mussel sampling and observations conducted in the northern Gulf of Alaska. This dataset consists of six comma separated files (.csv): 1) mussel sampling site layout information, 2) mussel counts for mussels greater than 20 millimeters in a quadrat, 3) mussel size measurements for mussels greater than 20 mi
Data for Gene Transcription Patterns in Response to Low Level Petroleum Contaminants in Mytilus trossulus from Field Sites and Harbors in Southcentral Alaska
Marine mussels are a ubiquitous and crucial component of the nearshore environment, and new genomic technologies exist to quantify molecular responses of individual mussels to stimuli, including exposure to polycyclic aromatic hydrocarbons (PAHs). We used gene-based assays of exposure and physiological function to assess lingering oil damage from the 1989 Exxon Valdez oil spill using the Pacific b
Sea Otter Gene Transcription Data from Kodiak, the Alaska Peninsula, and Prince William Sound, Alaska, 2005-2012
This data set includes capture location, date, sex, and results of molecular gene transcription analysis for sea otters (Enhydra lutris) sampled in western Prince William Sound (WPWS), Alaska and comparison samples collected from Kodiak and the Alaska Peninsula, and reference samples collected from captive animals. Samples were collected between 2005 and 2012.
(Molecular gene transcription is t
SUPERSEDED: Gulf Watch Alaska Nearshore Component: Intertidal Mussel Site Data from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park, 2016
This data release has been SUPERSEDED. No data are provided here. Data from Gulf Watch Alaska nearshore mussel sampling data releases have been appended to U.S. Geological Survey data release: https://doi.org/10.5066/F7FN1498.
This data is part of the Gulf Watch Alaska (GWA) long term monitoring program, nearshore monitoring component. Specifically, these data describe mussel sampling and observa
Filter Total Items: 71
Lack of strong responses to the Pacific marine heatwave by benthivorous marine birds indicates importance of trophic drivers
The Pacific marine heatwave (PMH) of 2014-2016 was an intense, long-lasting environmental disturbance expressed throughout the north Pacific. While dramatic consequences of the PMH on pelagic food webs have been well documented, effects on nearshore food webs, i.e., those based on macroalgae primary productivity, benthic invertebrate intermediate consumers, and specialized benthivorous top predato
Authors
Brian H. Robinson, Heather A. Coletti, Brenda Ballachey, James L. Bodkin, Kimberly A. Kloecker, Sarah Beth Traiger, Daniel Esler
Nearshore ecosystems in the Gulf of Alaska
Nearshore ecosystem monitoring in western Prince William Sound, Kenai Fjords National Park, Kachemak Bay, and Katmai National Park and Preserve has been conducted as a single Nearshore Component of the Gulf Watch Alaska program over the past five years (2017-2021). This program builds on the previous five years and continues, in many cases, decades of preceding research and monitoring. During the
Authors
Heather A. Coletti, Daniel Esler, Brenda Ballachey, Jim Bodkin, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Brian H. Robinson, Sarah Beth Traiger, Katrin Iken, Brenda Konar, Tom Dean, Mandy Lindeberg, Ben Weitzman
Gene expression and wildlife health: Varied interpretations based on perspective
We evaluated wildlife population health from the perspective of statistical means vs. variances. We outlined the choices necessary to provide the framework for our study. These consisted of spatial and temporal boundaries (e.g., choice of sentinel species, populations, time frame), measurement techniques (molecular to population level), and appropriate statistical analyses. We chose to assess the
Authors
Lizabeth Bowen, Julie L. Yee, James L. Bodkin, Shannon C. Waters, Michael J. Murray, Heather Coletti, Brenda E. Ballachey, Daniel Monson, A. Keith Miles
The mysterious case of the missing razor clams
Oceans are changing and these changes are affecting animals that live there. Animals respond differently to changes in water temperature, food availability, or contaminants. Those responses can be seen in their genes. Gene transcription is a tool that allows scientists to see the response of an animal’s genes to its environment. We used gene transcription to compare two populations of Pacific razo
Authors
Heather Coletti, Lizabeth Bowen, Brenda Ballachey, Tammy L. Wilson, Shannon C. Waters, Michael Booz, Katrina Counihan, Tuula E. Hollmen, Benjamin Pister
Divergent gene expression profiles in Alaskan sea otters: An indicator of chronic domoic acid exposure?
An opportunistic investigation into ecosystem instability in Kachemak Bay (KBay), Alaska, has led us to investigate exposure to toxic algae in sea otters. We used gene expression to explore the physiological health of sea otters sampled in KBay in May 2019. We found altered levels of gene transcripts in comparison with reference sea otters from clinically normal, oil-exposed, and nutritionally cha
Authors
Lizabeth Bowen, Susan Knowles, Kathi Lefebvre, Michelle St Martin, Michael Murray, Kimberly A. Kloecker, Daniel Monson, Ben Weitzman, Brenda Ballachey, Heather Coletti, Shannon C. Waters, C Cummings
Evidence of increased mussel abundance related to the Pacific marine heatwave and sea star wasting
Mussels occupy a key middle trophic position in nearshore food webs linking primary producers to predators. Climate-related environmental changes may synergistically combine with changes in predator abundance to affect intertidal ecosystems. We examined the influence of two major events on mussel (Mytilus trossulus) abundance in the northern Gulf of Alaska: the recent Pacific marine heatwave (PMH,
Authors
Sarah Beth Traiger, James L. Bodkin, Heather Coletti, Brenda Ballachey, Dean Thomas, Daniel Esler, Katrin Iken, Brenda Konar, Mandy Lindeberg, Daniel Monson, Brian H. Robinson, Robert M. Suryan, Ben Weitzman
Gene expression profiles in two razor clam populations: Discerning drivers of population status
With rapidly changing marine ecosystems, shifts in abundance and distribution are being documented for a variety of intertidal species. We examined two adjacent populations of Pacific razor clams (Siliqua patula) in lower Cook Inlet, Alaska. One population (east) supported a sport and personal use fishery, but this has been closed since 2015 due to declines in abundance, and the second population
Authors
Heather A. Coletti, Lizabeth Bowen, Brenda Ballachey, Tammy L. Wilson, Shannon C. Waters, Michael Booz, Katrina L Counihan, Tuula E. Hollmen, Benjamin Pister
Sea otter population collapse in southwest Alaska: Assessing ecological covariates, consequences, and causal factors
Sea otter (Enhydra lutris) populations in southwest Alaska declined substantially between about 1990 and the most recent set of surveys in 2015. Here we report changes in the distribution and abundance of sea otters, and covarying patterns in reproduction, mortality, body size and condition, diet and foraging behavior, food availability, health profiles, and exposure to environmental contaminants
Authors
M. Tim Tinker, James L. Bodkin, Lizabeth Bowen, Brenda Ballachey, Gena Bentall, Alexander Burdin, Heather Coletti, George G. Esslinger, Brian B. Hatfield, Michael C. Kenner, Kimberly A. Kloecker, Brenda Konar, A. Keith Miles, Daniel Monson, Michael J. Murray, Ben Weitzman, James A. Estes
Monitoring nearshore ecosystem health using Pacific razor clams (Siliqua patula) as an indicator species
An emerging approach to ecosystem monitoring involves the use of physiological biomarker analyses in combination with gene transcription assays. For the first time, we employed these tools to evaluate the Pacific razor clam (Siliqua patula), which is important both economically and ecologically, as a bioindicator species in the northeast Pacific. Our objectives were to (1) develop biomarker and ge
Authors
Lizabeth Bowen, Katrina Counihan, Brenda E. Ballachey, Heather A Colletti, Tuula E. Hollmen, Benjamin Pister, Tammy L Wilson
Timelines and mechanisms of wildlife population recovery following the Exxon Valdez oil spill
Research and monitoring activities over the 28 years since the T/V Exxon Valdez ran aground and spilled oil into Prince William Sound, Alaska have led to an improved understanding of how wildlife populations were damaged, as well as the mechanisms and timelines of recovery. A key finding was that for some species, such as harlequin ducks and sea otters, chronic oil spill effects persisted for at l
Authors
Daniel Esler, Brenda E. Ballachey, Craig O. Matkin, Daniel Cushing, Robert Kaler, James L. Bodkin, Daniel Monson, George G. Esslinger, Kimberly A. Kloecker
Variation in abundance of Pacific Blue Mussel (Mytilus trossulus) in the Northern Gulf of Alaska, 2006–2015
Mussels are conspicuous and ecologically important components of nearshore marine communities around the globe. Pacific blue mussels (Mytilus trossulus) are common residents of intertidal habitats in protected waters of the North Pacific, serving as a conduit of primary production to a wide range of nearshore consumers including predatory invertebrates, sea ducks, shorebirds, sea otters, humans, a
Authors
James L. Bodkin, Heather A. Coletti, Brenda E. Ballachey, Daniel Monson, Daniel Esler, Thomas A. Dean
Gene transcription patterns in response to low level petroleum contaminants in Mytilus trossulus from field sites and harbors in southcentral Alaska
The 1989 Exxon Valdez oil spill damaged a wide range of natural resources, including intertidal communities, and post-spill studies demonstrated acute and chronic exposure and injury to an array of species. Standard toxicological methods to evaluate petroleum contaminants have assessed tissue burdens, with fewer assays providing indicators of health or physiology, particularly when contaminant lev
Authors
Lizabeth Bowen, A. Keith Miles, Brenda E. Ballachey, Shannon C. Waters, James L. Bodkin, Mandy Lindeberg, Daniel Esler
Science and Products
Intertidal Temperature Data from Kachemak Bay, Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
These data are part of the Gulf Watch Alaska (GWA) long-term monitoring program. This dataset consists of date, time, and temperature measurements from intertidal rocky sampling sites, including predicted tide height at the time of the reading, which is used to distinguish air from water temperature readings. The data are provided as comma separated values (.csv) files derived from data downloaded
Intertidal Mussel (Mytilus) Data from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
These data are part of the Gulf Watch Alaska (GWA) long-term monitoring program and describe mussel sampling and observations conducted in the northern Gulf of Alaska. This dataset consists of six comma separated files (.csv): 1) mussel sampling site layout information, 2) mussel counts for mussels greater than 20 millimeters in a quadrat, 3) mussel size measurements for mussels greater than 20 mi
Data for Gene Transcription Patterns in Response to Low Level Petroleum Contaminants in Mytilus trossulus from Field Sites and Harbors in Southcentral Alaska
Marine mussels are a ubiquitous and crucial component of the nearshore environment, and new genomic technologies exist to quantify molecular responses of individual mussels to stimuli, including exposure to polycyclic aromatic hydrocarbons (PAHs). We used gene-based assays of exposure and physiological function to assess lingering oil damage from the 1989 Exxon Valdez oil spill using the Pacific b
Sea Otter Gene Transcription Data from Kodiak, the Alaska Peninsula, and Prince William Sound, Alaska, 2005-2012
This data set includes capture location, date, sex, and results of molecular gene transcription analysis for sea otters (Enhydra lutris) sampled in western Prince William Sound (WPWS), Alaska and comparison samples collected from Kodiak and the Alaska Peninsula, and reference samples collected from captive animals. Samples were collected between 2005 and 2012.
(Molecular gene transcription is t
SUPERSEDED: Gulf Watch Alaska Nearshore Component: Intertidal Mussel Site Data from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park, 2016
This data release has been SUPERSEDED. No data are provided here. Data from Gulf Watch Alaska nearshore mussel sampling data releases have been appended to U.S. Geological Survey data release: https://doi.org/10.5066/F7FN1498.
This data is part of the Gulf Watch Alaska (GWA) long term monitoring program, nearshore monitoring component. Specifically, these data describe mussel sampling and observa
Filter Total Items: 71
Lack of strong responses to the Pacific marine heatwave by benthivorous marine birds indicates importance of trophic drivers
The Pacific marine heatwave (PMH) of 2014-2016 was an intense, long-lasting environmental disturbance expressed throughout the north Pacific. While dramatic consequences of the PMH on pelagic food webs have been well documented, effects on nearshore food webs, i.e., those based on macroalgae primary productivity, benthic invertebrate intermediate consumers, and specialized benthivorous top predato
Authors
Brian H. Robinson, Heather A. Coletti, Brenda Ballachey, James L. Bodkin, Kimberly A. Kloecker, Sarah Beth Traiger, Daniel Esler
Nearshore ecosystems in the Gulf of Alaska
Nearshore ecosystem monitoring in western Prince William Sound, Kenai Fjords National Park, Kachemak Bay, and Katmai National Park and Preserve has been conducted as a single Nearshore Component of the Gulf Watch Alaska program over the past five years (2017-2021). This program builds on the previous five years and continues, in many cases, decades of preceding research and monitoring. During the
Authors
Heather A. Coletti, Daniel Esler, Brenda Ballachey, Jim Bodkin, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Brian H. Robinson, Sarah Beth Traiger, Katrin Iken, Brenda Konar, Tom Dean, Mandy Lindeberg, Ben Weitzman
Gene expression and wildlife health: Varied interpretations based on perspective
We evaluated wildlife population health from the perspective of statistical means vs. variances. We outlined the choices necessary to provide the framework for our study. These consisted of spatial and temporal boundaries (e.g., choice of sentinel species, populations, time frame), measurement techniques (molecular to population level), and appropriate statistical analyses. We chose to assess the
Authors
Lizabeth Bowen, Julie L. Yee, James L. Bodkin, Shannon C. Waters, Michael J. Murray, Heather Coletti, Brenda E. Ballachey, Daniel Monson, A. Keith Miles
The mysterious case of the missing razor clams
Oceans are changing and these changes are affecting animals that live there. Animals respond differently to changes in water temperature, food availability, or contaminants. Those responses can be seen in their genes. Gene transcription is a tool that allows scientists to see the response of an animal’s genes to its environment. We used gene transcription to compare two populations of Pacific razo
Authors
Heather Coletti, Lizabeth Bowen, Brenda Ballachey, Tammy L. Wilson, Shannon C. Waters, Michael Booz, Katrina Counihan, Tuula E. Hollmen, Benjamin Pister
Divergent gene expression profiles in Alaskan sea otters: An indicator of chronic domoic acid exposure?
An opportunistic investigation into ecosystem instability in Kachemak Bay (KBay), Alaska, has led us to investigate exposure to toxic algae in sea otters. We used gene expression to explore the physiological health of sea otters sampled in KBay in May 2019. We found altered levels of gene transcripts in comparison with reference sea otters from clinically normal, oil-exposed, and nutritionally cha
Authors
Lizabeth Bowen, Susan Knowles, Kathi Lefebvre, Michelle St Martin, Michael Murray, Kimberly A. Kloecker, Daniel Monson, Ben Weitzman, Brenda Ballachey, Heather Coletti, Shannon C. Waters, C Cummings
Evidence of increased mussel abundance related to the Pacific marine heatwave and sea star wasting
Mussels occupy a key middle trophic position in nearshore food webs linking primary producers to predators. Climate-related environmental changes may synergistically combine with changes in predator abundance to affect intertidal ecosystems. We examined the influence of two major events on mussel (Mytilus trossulus) abundance in the northern Gulf of Alaska: the recent Pacific marine heatwave (PMH,
Authors
Sarah Beth Traiger, James L. Bodkin, Heather Coletti, Brenda Ballachey, Dean Thomas, Daniel Esler, Katrin Iken, Brenda Konar, Mandy Lindeberg, Daniel Monson, Brian H. Robinson, Robert M. Suryan, Ben Weitzman
Gene expression profiles in two razor clam populations: Discerning drivers of population status
With rapidly changing marine ecosystems, shifts in abundance and distribution are being documented for a variety of intertidal species. We examined two adjacent populations of Pacific razor clams (Siliqua patula) in lower Cook Inlet, Alaska. One population (east) supported a sport and personal use fishery, but this has been closed since 2015 due to declines in abundance, and the second population
Authors
Heather A. Coletti, Lizabeth Bowen, Brenda Ballachey, Tammy L. Wilson, Shannon C. Waters, Michael Booz, Katrina L Counihan, Tuula E. Hollmen, Benjamin Pister
Sea otter population collapse in southwest Alaska: Assessing ecological covariates, consequences, and causal factors
Sea otter (Enhydra lutris) populations in southwest Alaska declined substantially between about 1990 and the most recent set of surveys in 2015. Here we report changes in the distribution and abundance of sea otters, and covarying patterns in reproduction, mortality, body size and condition, diet and foraging behavior, food availability, health profiles, and exposure to environmental contaminants
Authors
M. Tim Tinker, James L. Bodkin, Lizabeth Bowen, Brenda Ballachey, Gena Bentall, Alexander Burdin, Heather Coletti, George G. Esslinger, Brian B. Hatfield, Michael C. Kenner, Kimberly A. Kloecker, Brenda Konar, A. Keith Miles, Daniel Monson, Michael J. Murray, Ben Weitzman, James A. Estes
Monitoring nearshore ecosystem health using Pacific razor clams (Siliqua patula) as an indicator species
An emerging approach to ecosystem monitoring involves the use of physiological biomarker analyses in combination with gene transcription assays. For the first time, we employed these tools to evaluate the Pacific razor clam (Siliqua patula), which is important both economically and ecologically, as a bioindicator species in the northeast Pacific. Our objectives were to (1) develop biomarker and ge
Authors
Lizabeth Bowen, Katrina Counihan, Brenda E. Ballachey, Heather A Colletti, Tuula E. Hollmen, Benjamin Pister, Tammy L Wilson
Timelines and mechanisms of wildlife population recovery following the Exxon Valdez oil spill
Research and monitoring activities over the 28 years since the T/V Exxon Valdez ran aground and spilled oil into Prince William Sound, Alaska have led to an improved understanding of how wildlife populations were damaged, as well as the mechanisms and timelines of recovery. A key finding was that for some species, such as harlequin ducks and sea otters, chronic oil spill effects persisted for at l
Authors
Daniel Esler, Brenda E. Ballachey, Craig O. Matkin, Daniel Cushing, Robert Kaler, James L. Bodkin, Daniel Monson, George G. Esslinger, Kimberly A. Kloecker
Variation in abundance of Pacific Blue Mussel (Mytilus trossulus) in the Northern Gulf of Alaska, 2006–2015
Mussels are conspicuous and ecologically important components of nearshore marine communities around the globe. Pacific blue mussels (Mytilus trossulus) are common residents of intertidal habitats in protected waters of the North Pacific, serving as a conduit of primary production to a wide range of nearshore consumers including predatory invertebrates, sea ducks, shorebirds, sea otters, humans, a
Authors
James L. Bodkin, Heather A. Coletti, Brenda E. Ballachey, Daniel Monson, Daniel Esler, Thomas A. Dean
Gene transcription patterns in response to low level petroleum contaminants in Mytilus trossulus from field sites and harbors in southcentral Alaska
The 1989 Exxon Valdez oil spill damaged a wide range of natural resources, including intertidal communities, and post-spill studies demonstrated acute and chronic exposure and injury to an array of species. Standard toxicological methods to evaluate petroleum contaminants have assessed tissue burdens, with fewer assays providing indicators of health or physiology, particularly when contaminant lev
Authors
Lizabeth Bowen, A. Keith Miles, Brenda E. Ballachey, Shannon C. Waters, James L. Bodkin, Mandy Lindeberg, Daniel Esler
*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