Megan La Peyre, PhD
Assistant Unit Leader - Louisiana Cooperative Fish and Wildlife Research Unit
Research Interests
Megan's research focuses on estuarine ecology. Her lab is engaged in field and laboratory studies examining fish and invertebrate use of natural, restored and created shallow estuarine habitats including the ecology and ecosystem function of oyster reefs.
Teaching Interests
Megan teaches classes related to restoration of estuarine coastal systems, and natural resources policy.
Professional Experience
Assistant Unit Leader, Louisiana Cooperative Fish and Wildlife Research Unit, 2000-
Education and Certifications
Ph D Louisiana State University 2000
MS College of William and Mary 1995
BA Duke University 1992
Science and Products
A Case Study Assessing the Cumulative Effects of Deepwater Horizon Restoration Projects on Barrier Island/Barrier Shoreline Ecosystem Resilience in the North-central Gulf of Mexico
USGS and partners will assess the potential cumulative effects of restoration projects on the resiliency of barrier islands and barrier shorelines in the north-central Gulf of Mexico.
A Roadmap for Developing Resilient Coastal Shellfish Populations: Using Spatial and Process-Based Modelling for Restoration Under Current and Predicted Future Water Quality Conditions
Estuaries support valuable recreation, fisheries, and aquaculture and are dependent on healthy and vibrant ecosystems. Along the northern Gulf of Mexico, estuaries sustain local economies through their high productivity. They also receive over 50% of the United States watershed discharge, and water quality within these estuaries is impacted by local management actions. Within these estuaries, eas
Model Improvements for Louisiana’s 2023 Coastal Master Plan
The Louisiana Coastal Protection and Restoration Authority’s Coastal Master Plan is a blueprint for responding to environmental changes. As part of the agency’s continued engagement, USGS supports model developments and improvements for the 2023 Coastal Master Plan.
Information supporting a cumulative effects assessment of restoration in barrier island and shoreline systems of the north central Gulf of Mexico
Information was gathered to support a cumulative effects assessment of restoration in barrier island and shoreline systems of the north central Gulf of Mexico. Information includes: 1) results from two literature searches to help guide the development of a conceptual model of a barrier island and shoreline system and identify drivers and stressors important to that system, and 2) an accounting of
Eastern oyster Dynamic Energy Budget model outputs under current (2014-2020) and projected (2041-2050) temperature and salinity conditions in Texas and Louisiana estuaries and along northern Gulf of Mexico coast
Compilation of all outputs from the modeling study presented in Lavaud et al. (2023; IP-156006). In this study a Dynamic Energy Budget (DEB) model for the eastern oyster, Crassostrea virginica, was run under different scenarios of current (2014–2020) and future (2041–2050) temperature and salinity conditions across six key Texas and Louisiana estuaries to derive an aquaculture index, based on surv
Bio-engineered oyster reef monitoring, Eloi Bay, Louisiana, 2017-2019
This dataset includes annual encrusting organism (oyster, mussel, barnacle) counts and density (ind m-2), and oyster shell height (mm) data for five bio-engineered reef designs: OysterbreakTM (OB), Wave Attenuating Device (WAD), Reef Ball (rows of two, RFB2; rows of three, RFB3), ReefBLK? (RBL), and ShoreJAX (JAX). Data were collected during winter months (i.e., December-January) in 2017, 2018, an
Seagrass habitat suitability modeling for the Alabama Barrier Island restoration assessment at Dauphin Island
A barrier island seagrass habitat suitability index (HSI) model was developed for the Alabama barrier island restoration assessment at Dauphin Island. Shoal grass (Halodule wrightii) was selected as the representative species for seagrass community near Dauphin Island waters since H. wrightii is the dominant species (>62%) of seagrass communities in this area due to its rapid growth and tolerance
Oyster habitat suitability modeling for the Alabama Barrier Island restoration assessment at Dauphin Island
A spatially explicit oyster habitat suitability index (HSI) model was developed for the Alabama barrier island restoration assessment at Dauphin Island. Based on previous oyster habitat suitability studies, seven water quality variables were selected and their relationships with habitat suitability were developed and incorporated into the oyster HSI model for Dauphin Island restoration assessment:
Seed biomass from shallow coastal water areas along a salinity gradient in Barataria Bay, Louisiana (2015)
This dataset provides bi-monthly data on seed biomass collected in shallow water habitats across the fresh to saline gradient at coastal sites in Barataria Bay, Louisiana.
Seed biomass from shallow coastal water areas from Texas through Alabama, 2013-2015
This projects primary goal was to provide data on biomass of potential seed resources located within shallow water coastal areas within fresh to saline coastal waters of the northern Gulf of Mexico. The data set provides biomass of seeds, by species or lowest practical taxon from 2013, 2014 and 2015 across 384 randomly selected sites located in shallow water coastal areas. The data were collected
Sediment carbon, submerged aquatic vegetation and environmental variables in deltaic southeast Louisiana (2015-2016)
These present data on sediment carbon from soil cores taken from within submerged aquatic vegetation beds from fresh to saline coastal locations in southeast Louisiana. Water quality, site location, vegetation biomass and species composition are recorded.
Data for Gulf Coast Vulnerability Assessment
This USGS Data Release represents geospatial and tabular data for the Gulf Coast Vulnerability Assessment Project. The data release was produced in compliance with the new 'open data' requirements as way to make the scientific products associated with USGS research efforts and publications available to the public. The dataset consists of 2 separate items:
1. Vulnerability assessment data for ha
Submerged aquatic vegetation and environmental data for coastal areas from Texas through Alabama, 2013-2015
This projects primary goal was to provide data on occurrence and abundance of SAV resources within the fresh to saline coastal waters of the northern Gulf of Mexico, and to relate these findings to key environmental variables. The data set provides the collected data from 2013, 2014 and 2015 on site location, discrete water quality, aquatic vegetation cover and biomass by species. The same 384 sit
Filter Total Items: 87
In-situ valve opening response of eastern oysters to estuarine conditions
High-frequency recordings of valve opening behavior (VOB) in bivalves are often used to detect changes in environmental conditions. However, generally a single variable such as temperature or the presence of toxicants in the water is the focus. A description of routine VOB under non-stressful conditions is also important for interpreting responses to environmental changes. Here we present the firs
Authors
Romain Lavaud, Stephanie K. Archer, Megan K. La Peyre, Finella M. Campanino, Sandra M. Casas, Jerome F. La Peyre
Rates of osmoconformation in triploid eastern oysters, and comparison to their diploid half-siblings
Triploid eastern oysters (Crassostrea virginica) suffer greater mortalities than diploids in the U.S. Gulf of Mexico estuaries when extreme low salinities (< 5) and elevated temperatures (≥ 28 °C) coincide. To investigate potential causes, changes in plasma osmolality, hemolymph pH, valve opening and mortality in diploid and triploid oyster half-siblings were compared during a step-down gradual ac
Authors
Sandra M. Casas, Devin Comba, Megan K. La Peyre, Scott Rikard, Jerome F. La Peyre
Hypoxia and anoxia tolerance in diploid and triploid eastern oysters at high temperature
Increasing reliance on the use of triploid oysters to support aquaculture production relies on their generally superior growth rate and meat quality over that of diploid oysters. Reports of elevated triploid mortality have generated questions about potential trade-offs between growth and tolerance to environmental stressors. These questions are particularly relevant as climate change, coastal acti
Authors
Nicholas Coxe, Genesis Mize, Sandra M. Casas, Megan K. La Peyre, Romain Lavaud, Brian Callam, Scott Rikard, Jerome F. La Peyre
DNA virome composition of two sympatric wild felids, bobcat (Lynx rufus) and puma (Puma concolor) in Sonora, Mexico
With viruses often having devastating effects on wildlife population fitness and wild mammals serving as pathogen reservoirs for potentially zoonotic diseases, determining the viral diversity present in wild mammals is both a conservation and One Health priority. Additionally, transmission from more abundant hosts could increase the extinction risk of threatened sympatric species. We leveraged an
Authors
Natalie Payne, Leigh Combrink, Simona Kraberger, Rafaela S. Fontenele, Kara Schmidlin, Ivonne Cassaigne, Megan K. La Peyre, Arvind Varsani, Koenraad Van Doorslaer
Differential hypoxia tolerance of eastern oysters from the northern Gulf of Mexico at elevated temperature
Increasing prevalence of hypoxia in shallow waters of U.S. Gulf of Mexico (GoM) estuaries can pose a serious threat to eastern oysters (Crassostrea virginica). Their tolerance to hypoxia, however, is not well characterized, especially at elevated temperatures (>30 °C) typical of GoM estuaries in summer. Moreover, it is unknown whether differences in hypoxia tolerance exist between GoM oyster popul
Authors
Nicholas Coxe, Sandra M. Casas, Danielle A. Marshall, Megan K. La Peyre, Morgan W. Kelly, Jerome F. La Peyre
Are we falling short on restoring oysters at a regional scale?
Across coastal areas of the northern Gulf of Mexico, the Deepwater Horizon oil spill resulted in significant ecological injury, and over 8 billion USD directed to restoration activities. Oyster restoration projects were implemented with regional goals of restoring oyster abundance, spawning stock, and population resilience. Measuring regional or large-scale ecosystem restoration outcomes challenge
Authors
Megan K. La Peyre, Danielle Aguilar Marshall, Sarah Catherine Leblanc Buie, Ann Hijuelos, Gregory Steyer
Long-term assessments are critical to determining persistence and shoreline protection from oyster reef nature-based coastal defenses
Nature-based coastal defense using bivalve reefs provides a potentially self-sustaining approach for regions facing high coastal land loss, relative sea level rise and increasing frequency and intensity of storms. Success of such nature-based coastal defense depends on the reef-building species' life history, habitat requirements, and ability to thrive through short-term and longer-term environme
Authors
Megan K. La Peyre, Sarah Catherine Leblanc Buie, Ryann Rossi, Brian J. Roberts
Local populations of eastern oyster from Louisiana differ in low salinity tolerance
Eastern oysters Crassostrea virginica support a critical commercial industry and provide many ecosystem services to coastal estuaries yet are currently threatened by changing estuarine conditions. A changing climate and the effects of river and coastal management are altering freshwater inflows into productive oyster areas, causing more frequent and extreme salinity exposure. Although eastern oyst
Authors
Lauren Swam, Megan K. La Peyre, Brian Callam, Jerome F. La Peyre
Defining oyster resource zones across coastal Louisiana for restoration and aquaculture
Eastern oysters (Crassostrea virginica) are a critical ecological and commercial resource in the northern Gulf of Mexico facing changing environmental conditions from river management and climate change. In Louisiana, USA, development of restored reefs, and off-bottom aquaculture would benefit from the identification of locations supportive of sustainable oyster populations (i.e., metapopulations)
Authors
Lauren M. Swam, Brady Couvillion, Brian Callam, Jerome F. La Peyre, Megan K. La Peyre
Nekton community dynamics within active and inactive deltas in a major river estuary: Potential implications for altered hydrology regimes
High fisheries production within estuaries is associated with coastal upwelling, tidal mixing, and land-based runoff facing increasing impacts from climate and human activities. Active river deltas receive large riverine inflows compared to inactive river deltas, providing contrasting estuaries to compare impacts of river inflow on estuarine nekton. We quantified nekton assemblages and stable isot
Authors
Caleb B. Taylor, John Andrew Nyman, Megan K. La Peyre
Five years of monitoring a bio-engineered living shoreline: Comparison of oyster population development by reef technology.
The Living Shoreline Demonstration Project (PO-148) used five bio-engineered reef technologies (Reef Balls in two configurations; Figure 1) acting as breakwaters to protect vulnerable shorelines. While the primary goal is to attenuate wave energy, the sustainability and success of these products as “living” shorelines are based on their ability to enhance oyster habitat, enabling the reef to maint
Authors
Lauren M. Swam, Danielle Aguilar Marshall, Megan K. La Peyre
Effects of sample gear on estuarine nekton assemblage assessments and food web model simulations
Long-term fisheries-independent sampling data inform population status and trends of species-specific biomass and are often used to drive biomass-based food web models such as the Comprehensive Aquatic Systems Model (CASM). Indicators such as total biomass and mean trophic level derived from these data and from CASM outputs inform management and facilitate assessments of on-going and predicted coa
Authors
Megan K. La Peyre, S. Sable, C. M. Taylor, Katherine S. Watkins, E. Kiskaddon, M. Baustian
Science and Products
A Case Study Assessing the Cumulative Effects of Deepwater Horizon Restoration Projects on Barrier Island/Barrier Shoreline Ecosystem Resilience in the North-central Gulf of Mexico
USGS and partners will assess the potential cumulative effects of restoration projects on the resiliency of barrier islands and barrier shorelines in the north-central Gulf of Mexico.
A Roadmap for Developing Resilient Coastal Shellfish Populations: Using Spatial and Process-Based Modelling for Restoration Under Current and Predicted Future Water Quality Conditions
Estuaries support valuable recreation, fisheries, and aquaculture and are dependent on healthy and vibrant ecosystems. Along the northern Gulf of Mexico, estuaries sustain local economies through their high productivity. They also receive over 50% of the United States watershed discharge, and water quality within these estuaries is impacted by local management actions. Within these estuaries, eas
Model Improvements for Louisiana’s 2023 Coastal Master Plan
The Louisiana Coastal Protection and Restoration Authority’s Coastal Master Plan is a blueprint for responding to environmental changes. As part of the agency’s continued engagement, USGS supports model developments and improvements for the 2023 Coastal Master Plan.
Information supporting a cumulative effects assessment of restoration in barrier island and shoreline systems of the north central Gulf of Mexico
Information was gathered to support a cumulative effects assessment of restoration in barrier island and shoreline systems of the north central Gulf of Mexico. Information includes: 1) results from two literature searches to help guide the development of a conceptual model of a barrier island and shoreline system and identify drivers and stressors important to that system, and 2) an accounting of
Eastern oyster Dynamic Energy Budget model outputs under current (2014-2020) and projected (2041-2050) temperature and salinity conditions in Texas and Louisiana estuaries and along northern Gulf of Mexico coast
Compilation of all outputs from the modeling study presented in Lavaud et al. (2023; IP-156006). In this study a Dynamic Energy Budget (DEB) model for the eastern oyster, Crassostrea virginica, was run under different scenarios of current (2014–2020) and future (2041–2050) temperature and salinity conditions across six key Texas and Louisiana estuaries to derive an aquaculture index, based on surv
Bio-engineered oyster reef monitoring, Eloi Bay, Louisiana, 2017-2019
This dataset includes annual encrusting organism (oyster, mussel, barnacle) counts and density (ind m-2), and oyster shell height (mm) data for five bio-engineered reef designs: OysterbreakTM (OB), Wave Attenuating Device (WAD), Reef Ball (rows of two, RFB2; rows of three, RFB3), ReefBLK? (RBL), and ShoreJAX (JAX). Data were collected during winter months (i.e., December-January) in 2017, 2018, an
Seagrass habitat suitability modeling for the Alabama Barrier Island restoration assessment at Dauphin Island
A barrier island seagrass habitat suitability index (HSI) model was developed for the Alabama barrier island restoration assessment at Dauphin Island. Shoal grass (Halodule wrightii) was selected as the representative species for seagrass community near Dauphin Island waters since H. wrightii is the dominant species (>62%) of seagrass communities in this area due to its rapid growth and tolerance
Oyster habitat suitability modeling for the Alabama Barrier Island restoration assessment at Dauphin Island
A spatially explicit oyster habitat suitability index (HSI) model was developed for the Alabama barrier island restoration assessment at Dauphin Island. Based on previous oyster habitat suitability studies, seven water quality variables were selected and their relationships with habitat suitability were developed and incorporated into the oyster HSI model for Dauphin Island restoration assessment:
Seed biomass from shallow coastal water areas along a salinity gradient in Barataria Bay, Louisiana (2015)
This dataset provides bi-monthly data on seed biomass collected in shallow water habitats across the fresh to saline gradient at coastal sites in Barataria Bay, Louisiana.
Seed biomass from shallow coastal water areas from Texas through Alabama, 2013-2015
This projects primary goal was to provide data on biomass of potential seed resources located within shallow water coastal areas within fresh to saline coastal waters of the northern Gulf of Mexico. The data set provides biomass of seeds, by species or lowest practical taxon from 2013, 2014 and 2015 across 384 randomly selected sites located in shallow water coastal areas. The data were collected
Sediment carbon, submerged aquatic vegetation and environmental variables in deltaic southeast Louisiana (2015-2016)
These present data on sediment carbon from soil cores taken from within submerged aquatic vegetation beds from fresh to saline coastal locations in southeast Louisiana. Water quality, site location, vegetation biomass and species composition are recorded.
Data for Gulf Coast Vulnerability Assessment
This USGS Data Release represents geospatial and tabular data for the Gulf Coast Vulnerability Assessment Project. The data release was produced in compliance with the new 'open data' requirements as way to make the scientific products associated with USGS research efforts and publications available to the public. The dataset consists of 2 separate items:
1. Vulnerability assessment data for ha
Submerged aquatic vegetation and environmental data for coastal areas from Texas through Alabama, 2013-2015
This projects primary goal was to provide data on occurrence and abundance of SAV resources within the fresh to saline coastal waters of the northern Gulf of Mexico, and to relate these findings to key environmental variables. The data set provides the collected data from 2013, 2014 and 2015 on site location, discrete water quality, aquatic vegetation cover and biomass by species. The same 384 sit
Filter Total Items: 87
In-situ valve opening response of eastern oysters to estuarine conditions
High-frequency recordings of valve opening behavior (VOB) in bivalves are often used to detect changes in environmental conditions. However, generally a single variable such as temperature or the presence of toxicants in the water is the focus. A description of routine VOB under non-stressful conditions is also important for interpreting responses to environmental changes. Here we present the firs
Authors
Romain Lavaud, Stephanie K. Archer, Megan K. La Peyre, Finella M. Campanino, Sandra M. Casas, Jerome F. La Peyre
Rates of osmoconformation in triploid eastern oysters, and comparison to their diploid half-siblings
Triploid eastern oysters (Crassostrea virginica) suffer greater mortalities than diploids in the U.S. Gulf of Mexico estuaries when extreme low salinities (< 5) and elevated temperatures (≥ 28 °C) coincide. To investigate potential causes, changes in plasma osmolality, hemolymph pH, valve opening and mortality in diploid and triploid oyster half-siblings were compared during a step-down gradual ac
Authors
Sandra M. Casas, Devin Comba, Megan K. La Peyre, Scott Rikard, Jerome F. La Peyre
Hypoxia and anoxia tolerance in diploid and triploid eastern oysters at high temperature
Increasing reliance on the use of triploid oysters to support aquaculture production relies on their generally superior growth rate and meat quality over that of diploid oysters. Reports of elevated triploid mortality have generated questions about potential trade-offs between growth and tolerance to environmental stressors. These questions are particularly relevant as climate change, coastal acti
Authors
Nicholas Coxe, Genesis Mize, Sandra M. Casas, Megan K. La Peyre, Romain Lavaud, Brian Callam, Scott Rikard, Jerome F. La Peyre
DNA virome composition of two sympatric wild felids, bobcat (Lynx rufus) and puma (Puma concolor) in Sonora, Mexico
With viruses often having devastating effects on wildlife population fitness and wild mammals serving as pathogen reservoirs for potentially zoonotic diseases, determining the viral diversity present in wild mammals is both a conservation and One Health priority. Additionally, transmission from more abundant hosts could increase the extinction risk of threatened sympatric species. We leveraged an
Authors
Natalie Payne, Leigh Combrink, Simona Kraberger, Rafaela S. Fontenele, Kara Schmidlin, Ivonne Cassaigne, Megan K. La Peyre, Arvind Varsani, Koenraad Van Doorslaer
Differential hypoxia tolerance of eastern oysters from the northern Gulf of Mexico at elevated temperature
Increasing prevalence of hypoxia in shallow waters of U.S. Gulf of Mexico (GoM) estuaries can pose a serious threat to eastern oysters (Crassostrea virginica). Their tolerance to hypoxia, however, is not well characterized, especially at elevated temperatures (>30 °C) typical of GoM estuaries in summer. Moreover, it is unknown whether differences in hypoxia tolerance exist between GoM oyster popul
Authors
Nicholas Coxe, Sandra M. Casas, Danielle A. Marshall, Megan K. La Peyre, Morgan W. Kelly, Jerome F. La Peyre
Are we falling short on restoring oysters at a regional scale?
Across coastal areas of the northern Gulf of Mexico, the Deepwater Horizon oil spill resulted in significant ecological injury, and over 8 billion USD directed to restoration activities. Oyster restoration projects were implemented with regional goals of restoring oyster abundance, spawning stock, and population resilience. Measuring regional or large-scale ecosystem restoration outcomes challenge
Authors
Megan K. La Peyre, Danielle Aguilar Marshall, Sarah Catherine Leblanc Buie, Ann Hijuelos, Gregory Steyer
Long-term assessments are critical to determining persistence and shoreline protection from oyster reef nature-based coastal defenses
Nature-based coastal defense using bivalve reefs provides a potentially self-sustaining approach for regions facing high coastal land loss, relative sea level rise and increasing frequency and intensity of storms. Success of such nature-based coastal defense depends on the reef-building species' life history, habitat requirements, and ability to thrive through short-term and longer-term environme
Authors
Megan K. La Peyre, Sarah Catherine Leblanc Buie, Ryann Rossi, Brian J. Roberts
Local populations of eastern oyster from Louisiana differ in low salinity tolerance
Eastern oysters Crassostrea virginica support a critical commercial industry and provide many ecosystem services to coastal estuaries yet are currently threatened by changing estuarine conditions. A changing climate and the effects of river and coastal management are altering freshwater inflows into productive oyster areas, causing more frequent and extreme salinity exposure. Although eastern oyst
Authors
Lauren Swam, Megan K. La Peyre, Brian Callam, Jerome F. La Peyre
Defining oyster resource zones across coastal Louisiana for restoration and aquaculture
Eastern oysters (Crassostrea virginica) are a critical ecological and commercial resource in the northern Gulf of Mexico facing changing environmental conditions from river management and climate change. In Louisiana, USA, development of restored reefs, and off-bottom aquaculture would benefit from the identification of locations supportive of sustainable oyster populations (i.e., metapopulations)
Authors
Lauren M. Swam, Brady Couvillion, Brian Callam, Jerome F. La Peyre, Megan K. La Peyre
Nekton community dynamics within active and inactive deltas in a major river estuary: Potential implications for altered hydrology regimes
High fisheries production within estuaries is associated with coastal upwelling, tidal mixing, and land-based runoff facing increasing impacts from climate and human activities. Active river deltas receive large riverine inflows compared to inactive river deltas, providing contrasting estuaries to compare impacts of river inflow on estuarine nekton. We quantified nekton assemblages and stable isot
Authors
Caleb B. Taylor, John Andrew Nyman, Megan K. La Peyre
Five years of monitoring a bio-engineered living shoreline: Comparison of oyster population development by reef technology.
The Living Shoreline Demonstration Project (PO-148) used five bio-engineered reef technologies (Reef Balls in two configurations; Figure 1) acting as breakwaters to protect vulnerable shorelines. While the primary goal is to attenuate wave energy, the sustainability and success of these products as “living” shorelines are based on their ability to enhance oyster habitat, enabling the reef to maint
Authors
Lauren M. Swam, Danielle Aguilar Marshall, Megan K. La Peyre
Effects of sample gear on estuarine nekton assemblage assessments and food web model simulations
Long-term fisheries-independent sampling data inform population status and trends of species-specific biomass and are often used to drive biomass-based food web models such as the Comprehensive Aquatic Systems Model (CASM). Indicators such as total biomass and mean trophic level derived from these data and from CASM outputs inform management and facilitate assessments of on-going and predicted coa
Authors
Megan K. La Peyre, S. Sable, C. M. Taylor, Katherine S. Watkins, E. Kiskaddon, M. Baustian