Wade fishing

People

We are a dedicated team of scientists committed to innovation in fisheries research

Greg Stunz Ph.D.

Director, Center for Sportfish Science and Conservation

We founded the CSSC in 2012 to serve as a hub for scientists interested in marine fisheries research focused on the many challenges that come with maintaining healthy sportfish populations, both inshore and offshore. Our goal is to ensure the most informed decisions are made when managing and conserving our valuable fisheries and the marine environment they inhabit. Many of us are anglers as well as scientists, and we invest our passion for the Gulf of Mexico and its dynamic fishery into the work we do every day.

Staff

Greg Stunz, PhD

Greg Stunz, Ph.D.

Director, Center for Sportfish Science and Conservation

Greg Stunz, Ph.D.

Greg Stunz, Ph.D. is a marine biologist that specializes in fisheries ecology and sport-fisheries. He was named the Interim Senior Executive Director of the Harte Research Institute for Gulf of Mexico Studies in November 2022. He is also the HRI Chair of Fisheries and Ocean Health, Director of the Center for Sportfish Science and Conservation, and a Professor of Marine Biology at Texas A&M University-Corpus Christi. He received both his M.S. and Ph.D. in Wildlife and Fisheries Sciences from Texas A&M University (1995, 1999), and a B.S. in Biology from the University of Texas at San Antonio (1990). A major goal of Dr. Stunz’s research program is to provide scientific data for sustainable management of our marine fisheries and ocean resources to ensure healthy environments.

Dr. Stunz's research program is diverse but currently focuses on migration patterns of marine life using a variety of state-of-the-art electronic tracking devices, diving and ROV studies of artificial reefs in the Gulf of Mexico, and the understanding the vital role that estuaries and near-shore waters play in sustaining marine populations. Specifically, his research includes understanding how artificial reefs enhance fisheries, the roles of apex predators (i.e., sharks) in Gulf ecosystems and tracking their movement patterns, dolphin-fish migration patterns and life history studies, red snapper ecology and management, several projects dealing with many estuarine fishes such as spotted seatrout and red drum and their sustainable management, and many others. Dr. Stunz is also engaged with numerous boards, panels, and scientific advisory committees from the local to national levels. In addition to numerous scientific publications, his research program is frequently covered by television, radio, print news and other media outlets.

For more information on Dr. Stunz visit: www.harteresearch.org

Office
Suite 318
Email
greg.stunz@tamucc.edu
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Matt Streich

Matt Streich, Ph.D.

Assistant Director, Center for Sportfish Science and Conservation & Associate Research Scientist

Dissertation

Matt Streich, Ph.D.

Dr. Matt Streich is the Assistant Director for the Center for Sportfish Science and Conservation at the Harte Research Institute for Gulf of Mexico Studies (HRI) at Texas A&M University-Corpus Christi. He is a broadly trained marine scientist with expertise in marine fisheries ecology and population dynamics. Dr. Streich’s research interests include marine sportfish life history, population connectivity, and distribution patterns and how they are influenced by fishing.

He earned his Ph.D. in marine biology in 2016 from Texas A&M University-Corpus Christi, where his dissertation research focused on better understanding the role artificial reefs and natural habitats like the South Texas Banks play in maintaining the Gulf of Mexico red snapper population. Some of his more recent research efforts have included evaluating seasonal movements and discard mortality of cobia using advanced electronic tagging approaches, estimating red snapper abundance in the western Gulf of Mexico, and examining the role of estuaries and nearshore waters in supporting healthy sportfish populations. Prior to arriving at HRI, Dr. Streich attended the University of Georgia where he earned B.S.F.R. (‘10) and M.S. (‘12) degrees in fisheries science. During this time, he gained valuable research experience in coastal Georgia studying a variety of species including Atlantic and shortnose sturgeon, bull sharks, and tripletail.

Office
Suite 311
Email
matthew.streich@tamucc.edu
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Kesley Banks

Kesley Banks, Ph.D.

Associate Research Scientist

Kesley Banks, Ph.D.

Kesley Banks is an Associate Research Scientist in the Center for Sportfish Science and Conservation at the Harte Research Institute for Gulf of Mexico Studies (HRI) at Texas A&M University-Corpus Christi. She graduated from Texas A&M University – Corpus Christi in December 2019 with a doctorate in marine biology. Under the mentorship of Dr. Greg Stunz, Kesley’s dissertation focused on movement patterns and habitat use for fishery species of varying life history strategies, including Red Snapper and Shortfin Mako sharks. Her research interests include movement patterns, habitat-use, and population connectivity of sportfish with an emphasis in coastal migratory pelagic and highly migratory species.

Kesley came to HRI after earning her M.S. in Environmental Science (2015) from Troy University where, as the ALFA Research Fellow, she studied federally threatened freshwater mollusks and their sensitivity to various toxicants lacking U.S. EPA Water Quality Criteria. Kesley received her B.S. in Biology (2012) at the University of Tennessee at Martin where she studied the evolutionary relationships within the Millipede suborder Spirobolidea.

Office
Suite 311
Email
Kesley.Banks@tamucc.edu
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Jeff Kaiser

Jeff Kaiser, M.S.

Research Specialist II

Jeff Kaiser, M.S.

Jeff Kaiser has been consumed with the ocean and fishing for, swimming with, and studying the fish and other creatures in it since childhood.  He received a B.S. in Biology from Baylor University and a M.S. in Mariculture from Texas A&M University Corpus Christi and has called the central Texas coast home for nearly thirty years.  During this time, he has had the opportunity to extensively explore both the inshore and offshore realms, conduct research on numerous marine fish in the laboratory, and live on an offshore platform in the Gulf of Mexico.

Past professional experience includes managing a marine fish laboratory with the goal of acquiring, maintaining, spawning, and conducting various research projects on numerous native species.  Mr. Kaiser was also involved in two offshore mariculture ventures and spent a combined five years as a project biologist and diver, gaining a keen appreciation for the ecosystem interactions on an artificial offshore structure. 

Research interests include the artificial reef program, the connection between science and marine recreational fisheries, and the socio-economic impact of marine fisheries on the Texas coast.   Mr. Kaiser will be helping operate the Sportfish Center laboratory as well as conducting field work and outreach activities.   

Office
HRI 311
Email
jeffrey.kaiser@tamucc.edu
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James Sanchez

James Sanchez, M.S.

Angler Engagement Coordinator

James Sanchez, M.S.

James Sanchez is the Angler Engagement Coordinator for the Center for Sportfish Science and Conservation at HRI. His passion for fishing steered him towards his career to educate anglers on science-based fishing practices to ensure healthy and sustainable fisheries along the Texas Gulf Coast.

He is a graduate of Texas A&M University-Corpus Christi, earning a Bachelor's in Marine Biology in 2012 and Master's in Biology in 2015. He has several years of research experience in Texas coastal ecology. As an undergraduate, he conducted research on how intraspecific variation influences settlement of eastern oysters (published in 2013). His master's thesis focused on how black mangrove expansion into salt marshes altered associated faunal communities (Published in 2017).

From 2016 to June 2023, James was a 7th grade science teacher who loved to share his passion and knowledge of science to his students. He utilized his research and teaching skills to enhance his students' understanding of how the natural world works, to think critically and independently, and learn how science plays a significant role in our society. On his own time, James is an outdoor writer and fishing guide that wades the waters of the Upper Laguna Madre and Baffin Bay chasing trout, redfish, and flounder.

Office
Suite 311
Email
james.sanchez@tamucc.edu
Jensen Smith

Jensen Smith

Research Program Associate

Jensen Smith

Throughout her upbringing in South Lake Tahoe, California, Jensen was always interested in marine life. Her undergraduate studies began at Humboldt State University, but her desire to study Gulf of Mexico marine life led to her to transfer to Texas A&M University-Corpus Christi. What Jensen enjoys most about her work as a Research Associate with the Fisheries & Ocean Health group is the opportunity to learn something new every day. When she’s not studying or working in the lab, Jensen enjoys spending her time outdoors both on and in the water.

Office
HRI 302
Email
jsmith89@islander.tamucc.edu
Tara Topping

Tara Topping, M.S.

Research Specialist II

Tara Topping, M.S.

Tara Topping is the project leader for iSnapper, a groundbreaking smartphone app launched by the Center for Sportfish Science and Conservation to easily collect fisheries data from recreational anglers. Tara’s interest in the ocean was sparked in childhood. Growing up in Connecticut, she was accepted into a tropical marine biology course that included a week-long trip to the now Bermuda Institute of Ocean Sciences, where she felt at home snorkeling among the coral reefs and excelled at reef fish biology. She later attended the University of Rhode Island and graduated magna cum laude with a bachelor’s degree in marine biology, and in 2011 received her master of science in marine fisheries and allied aquacultures from Auburn University. After graduating, she moved to Florida to monitor fisheries with the Florida Fish and Wildlife Conservation Commission in the Big Bend area.

Since joining CSSC in June 2014, Tara has assisted with projects including tagging large migratory sharks, diver and ROV (remotely operated vehicle) surveys of artificial reefs and inshore sampling on the newly-dredged Cedar Bayou.

Office
Suite 311
Email
tara.topping@tamucc.edu
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Jennifer Wetz

Jennifer Wetz, M.S.

Fisheries Program Manager

Jennifer Wetz, M.S.

Jennifer Wetz is the Fisheries Program Manager for the Center for Sportfish Science and Conservation.  

After receiving her bachelor’s degree in ecology from the University of Georgia in 1996, Jennifer earned a master’s degree in marine science from the University of South Florida, where she focused on the reproductive biology of grouper. Subsequent moves to South Carolina, Oregon and North Carolina resulted in a broad scientific background that includes research experience in water chemistry, molecular biology and microbiology. A move to Texas in 2011 to work for the Harte Research Institute finally reunited her with her favorite research topic: fisheries.

During her time at HRI, Jennifer has led the development of various survey techniques to assess reef fish populations across artificial and natural habitats. Currently she works closely with leadership to manage operations of the Center, but she also remains actively engaged in the Center’s research projects. 

Office
Suite 311
Email
jennifer.wetz@tamucc.edu
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Jason Williams

Jason Williams, M.S.

Research Specialist II

Thesis

Jason Williams, M.S.

Jason Williams is a Research Specialist for the Center for Sportfish Science and Conservation, where he specializes in larval fish ecology, GIS, and leads inshore and offshore field operations for the Center.

After graduating with his bachelor’s degree in ecology, evolution and conservation from the University of Texas at Austin, he moved to Port Aransas, ready to pursue a life in and around the water. Jason worked for six years as a lab tech in the University of Texas Marine Science Institute’s larval fish ecology lab before enrolling in the Masters of Biology program at Texas A&M Corpus Christi in 2008. There, under the guidance of Dr. Greg Stunz, he studied the effects of seagrass fragmentation on local marine life and joined the Harte Research Institute’s staff full time in 2011.

Office
Suite 311
Email
jason.williams@tamucc.edu

Students

Isabel Tiller

Graduate Research Assistant

Isabel Tiller

Office
HRI 311
Email
itiller@islander.tamucc.edu
Isabelle Cummings

Isabelle Cummings

MS Student

Isabelle Cummings

Isabelle was born in Wylie, Texas in 2002 and grew up with five other siblings. She was homeschooled most of her life but found numerous volunteering opportunities in aquariums and nonprofit organizations in the area. From these experiences, she developed a love for the ocean that later inspired her to attend Texas A&M University-Corpus Christi.

After attaining a bachelor’s degree of marine biology in 2021, she remains at TAMU-CC to attend graduate school and work with the Harte Research Institute for Gulf of Mexico Studies under Dr. Greg Stunz in the Fisheries and Ocean Health Laboratory. She is currently working with other members of the Fisheries Lab to study flounder populations and how to prevent their continuous population decline. She aspires to continue her studies of fisheries and ocean health throughout her education as well as obtain the knowledge and skills needed to excel in her future career.

Office
Suite 311
Email
icummings@islander.tamucc.edu
Robinson McMillan

Robinson McMillan

MS Student

Robinson McMillan

Rob was born and raised in Corpus Christi, Texas, and graduated from W.B. Ray High School. He attended Texas A&M University in College Station, where he earned a B.S. in Wildlife and Fisheries Sciences ('17). After graduation, he commissioned as an officer in the United States Navy and served for five years as a Surface Warfare Officer onboard USS Arleigh Burke, a guided missile destroyer.

Growing up in the Coastal Bend, Rob developed a love for the outdoors and an interest in the wildlife that call the Gulf of Mexico home. At TAMU-CC and HRI, he plans to study inshore marine fisheries and pursue a career in coastal conservation.

Office
HRI 311
Email
rmcmillan1@islander.tamucc.edu

Alumni

Kelsey Martin

Kelsey Martin, Ph.D.

Kelsey Martin, Ph.D.

Kelsey Martin graduated from Texas A&M University Corpus Christi in Summer 2022 with a Ph.D. in Marine Biology with her dissertation entitled “The Role of Artificial Reefs and Natural Banks in the Distribution and Abundance of Economically Important Fishes”. Kelsey grew up spending her summers in the Outer Banks of North Carolina and always knew she would pursue a career in the marine sciences. After graduating magna cum laude with a B.S. in Marine Science from Coastal Carolina University, she spent seven months working with sharks as a volunteer at the Bimini Biological Field Station Foundation in Bimini, Bahamas. She then worked on commercial fishing vessels in the North Pacific and the Bering Sea as a fisheries observer for Alaskan Observers Inc.. Then in 2015, she went back to school and obtained her M.S. in Coastal Marine and Wetland Studies from Coastal Carolina University in December 2017. 

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Jill Thompson-Grim

Jill Thompson-Grim, M.S.

Program: M.S., Marine Biology

Jill Thompson-Grim, M.S.

Jill Thompson-Grim is a Master’s student in the marine biology program and is working at the Harte Research Institute Center for Sportfish Science and Conservation. Jill grew up in the Houston area, and has always had an interest in understanding what happens under the ocean’s surface. Jill began her path of discovering more about the ocean when she started as an undergraduate marine biology student at Texas A&M University at Galveston in 2014.

During her time as an undergraduate, Jill was exposed to fisheries science through organizations including Texas Parks and Wildlife Artificial Reef Program and NOAA. As an undergraduate research scholar, Jill conducted research that focused on detecting and quantifying the relative abundance of Lionfish using the environmental DNA shed into the water column. Now as a new Master’s student, Jill hopes to continue her education in Marine Biology while studying Red Snapper populations in the Gulf of Mexico.

Jill joined the CSSC in July of 2018.

Office
Suite 311
Email
jthompsongrim@tamucc.edu
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Kesley Banks

Kesley Banks, Ph.D.

Associate Research Scientist

Kesley Banks, Ph.D.

Kesley Banks is an Associate Research Scientist in the Center for Sportfish Science and Conservation at the Harte Research Institute for Gulf of Mexico Studies (HRI) at Texas A&M University-Corpus Christi. She graduated from Texas A&M University – Corpus Christi in December 2019 with a doctorate in marine biology. Under the mentorship of Dr. Greg Stunz, Kesley’s dissertation focused on movement patterns and habitat use for fishery species of varying life history strategies, including Red Snapper and Shortfin Mako sharks. Her research interests include movement patterns, habitat-use, and population connectivity of sportfish with an emphasis in coastal migratory pelagic and highly migratory species.

Kesley came to HRI after earning her M.S. in Environmental Science (2015) from Troy University where, as the ALFA Research Fellow, she studied federally threatened freshwater mollusks and their sensitivity to various toxicants lacking U.S. EPA Water Quality Criteria. Kesley received her B.S. in Biology (2012) at the University of Tennessee at Martin where she studied the evolutionary relationships within the Millipede suborder Spirobolidea.

Office
Suite 311
Email
Kesley.Banks@tamucc.edu
CV
Zach Olsen

Zach Olsen, M.S.

Program: Ph.D., Coastal Marine System Science

Zach Olsen, M.S.

Zach Olsen is a PhD student in the Center for Sportfish Science and Conservation (CSSC). Concurrent with his PhD research, he works full time for the Texas Parks and Wildlife Department (TPWD) Habitat Assessment Team. Zach’s research interests both at CSSC and at TPWD focus primarily on the link between habitat and fisheries populations and the use of advanced statistical, machine learning, and modeling techniques for finding relevant patterns and trends that can be used for making sound management decisions regarding the long-term conservation of our coastal resources.

Prior to coming to CSSC and TPWD, Zach received his B.A. in Biology from Malone University in Canton Ohio and his M.S. degree in Coastal Sciences from the University of Southern Mississippi- Gulf Coastal Research Laboratory in Ocean Springs, Mississippi.

Office
NRC 2500
Email
zachary.olsen@tpwd.texas.gov
CV
Alex Tompkins

Alex Tompkins, M.S.

Thesis

Alex Tompkins, M.S.

Matt Streich

Matt Streich, Ph.D.

Assistant Director, Center for Sportfish Science and Conservation & Associate Research Scientist

Dissertation

Matt Streich, Ph.D.

Dr. Matt Streich is the Assistant Director for the Center for Sportfish Science and Conservation at the Harte Research Institute for Gulf of Mexico Studies (HRI) at Texas A&M University-Corpus Christi. He is a broadly trained marine scientist with expertise in marine fisheries ecology and population dynamics. Dr. Streich’s research interests include marine sportfish life history, population connectivity, and distribution patterns and how they are influenced by fishing.

He earned his Ph.D. in marine biology in 2016 from Texas A&M University-Corpus Christi, where his dissertation research focused on better understanding the role artificial reefs and natural habitats like the South Texas Banks play in maintaining the Gulf of Mexico red snapper population. Some of his more recent research efforts have included evaluating seasonal movements and discard mortality of cobia using advanced electronic tagging approaches, estimating red snapper abundance in the western Gulf of Mexico, and examining the role of estuaries and nearshore waters in supporting healthy sportfish populations. Prior to arriving at HRI, Dr. Streich attended the University of Georgia where he earned B.S.F.R. (‘10) and M.S. (‘12) degrees in fisheries science. During this time, he gained valuable research experience in coastal Georgia studying a variety of species including Atlantic and shortnose sturgeon, bull sharks, and tripletail.

Office
Suite 311
Email
matthew.streich@tamucc.edu
CV
Chas Downey

Chas Downey, M.S.

M.S.Marine Biology Student

Thesis

Chas Downey, M.S.

Chas is working on Red Snapper reproduction and diet analysis between several structure types present in the Western Gulf of Mexico.

Office
Suite 315
Quentin Hall

Quentin Hall, M.S.

Research Specialist II

Thesis

Quentin Hall, M.S.

Phil Jose

Phil Jose, M.S.

Former Graduate Student

Thesis

Phil Jose, M.S.

Peter Young

Peter Young, M.S.

Thesis

Peter Young, M.S.

Jason Slocum

Jason Slocum, M.S.

Former Graduate Student

Thesis

Jason Slocum, M.S.

Thesis Title: Macrofaunal food web structure associated with subtidal and intertidal oyster reefs and non-vegetated bottom in the Mission-Aransas estuary

Abstract: Examining food web dynamics is important for identifying species interactions. Tracking energy flow between organisms within habitats clarifies the ecological functions between predators and their prey. Understanding the interactions between organisms and the energy flows within habitats is critical in explaining estuarine ecosystem productivity and structure. The purpose of this study was to examine macrofaunal food web structure associated with subtidal and intertidal oyster reefs and non-vegetated bottom in the Mission-Aransas estuarine system. Food webs were analyzed by combining stomach content analysis and stable isotope techniques. Sampling occurred seasonally from November 2008 to September 2009. A total of 5226 macroinvertebrates and fishes were collected using a modified epi-benthic sled and multi-sized mesh gill nets for both stomach content and stable isotope analyses. Vegetation, particulate organic matter, and benthic organic matter were also collected for stable isotope analysis. Diet preference was reflected as the Percent Index of Relative Importance (%IRI) and showed that decapod crabs, and Crassostrea virginica were the top prey items for predators within the system. Gut content analysis showed a high number (35%) of empty stomachs which could indicate that food availability and resource acquisition may be deficient in the system. The system was going through a historic drought, and experienced high salinities (40+ ppt) and reduced freshwater inflows, and these extreme abiotic conditions may have altered food webs during the course of study. Nonetheless, this study provides food web information that are useful in planning fisheries population management when droughts are expected, and for comparative purposes during "normal" environmental conditions.

Karen Drumhiller

Karen Drumhiller, M.S.

Former Graduate Student

Thesis

Karen Drumhiller, M.S.

Thesis Title: Venting and Rapid Recompression Increase Survival and Improve Recovery for Red Snapper with Barotrauma

Abstract: Red Snapper, Lutjanus campechanus, are the most economically important reef fish in the Gulf of Mexico. Population assessments that began in the mid-1980’s found red snapper to be severely overfished and lead to extensive regulations and harvest restrictions. As a result of these regulations many fish that are captured must be released and are known as regulatory discards. Red snapper live deep in the water column and when captured and rapidly brought to the surface they often suffer pressure-related injuries collectively known as barotrauma. These injuries include a distended abdomen and stomach eversion from the buccal cavity. High mortality of discards due to barotrauma injuries impedes recovery of the fishery. The purpose of this study was to evaluate the efficacy of two techniques designed to minimize barotrauma-related mortality: venting and rapid recompression. In laboratory experiments using hyperbaric chambers, I assessed sublethal effects of barotrauma and subsequent survival rates of red snapper after single and multiple simulated capture events from pressures corresponding to 30 and 60 m. I evaluated the use of rapid recompression and venting to increase survival and improve recovery indices, including the ability to evade a simulated predator. A condition index of impairment, the barotrauma reflex (BtR) score, was used to assess sublethal external barotrauma injuries, reflex responses, and behavioral responses. Greater capture depths resulted in higher BtR scores (more impairment). Nonvented fish had higher BtR scores than vented fish after both single and multiple decompression events. All fish in vented treatments from 30 and 60 m depths had 100% survival after a single capture event. Non-vented fish had 67% survival after decompression from 30 m and 17% survival from 60 m. Behaviorally, non-vented fish ii showed greater difficulty achieving an upright orientation upon release and less ability to evade a simulated predator than vented fish. Rapid recompression also greatly improved survival compared to surface-released fish with 96% of all rapidly recompressed fish surviving. These results clearly show that venting or rapid recompression can be effective tools for alleviating barotrauma symptoms, improving predator evasion after a catch-andrelease event, and increasing survival. Fisheries managers should encourage the use of either of these two techniques to aid in the recovery of this important fishery.

Kim Johnson, M.S.

Kim Johnson, M.S.

Former Graduate Student

Thesis

Kim Johnson, M.S.

Thesis Title: Changes in groundfish community structure and diversity in the northern Gulf of Mexico during the last 2 decades

Abstract: Changes in diversity indices and community structure of the Gulf of Mexico were examined between 1987 and 2010 using univariate and multivariate statistical approaches. Trawl data were used from the National Marine Fisheries Service (NMFS) summer Southeast Assessment and Monitoring Program (SEAMAP) shrimp/bottomfish survey in the Gulf of Mexico (Gulf) between 1987 and 2010. The primary habitat sampled consisted of unstructured seafloor, including soft (sandy or muddy) bottoms or hard (shell-hash or hard-ground) bottom. Diversity and community structure was tested against temporal, spatial, or abiotic variables. Species diversity measures consisted of: number of individuals, number of species, richness, evenness, Simpson’s and Shannon’s diversity indices. Environmental parameters examined were depth (m), temperature (◦C), dissolved oxygen (mg-l ) (dO2), and salinity. Diversity indices significantly increased temporally from the Mississippi River Basin to Brownsville, TX between1987 and 2010 and spatially across the study area in a southwesterly direction. Multivariate partial least squares analysis (PLS) showed dissolved oxygen, depth, and statistical zone contributed 14.6% of the response variable. In general, the community structure between 1987 and 2010 became more consistent. Gulf-wide, the community structure was correlated with depth and DO (49%) or temperature and DO (48%). Dissolved oxygen influences community structure near the Mississippi River outfall but is less important elsewhere. Overall, the Gulf is incredibly complex and no single temporal, spatial or environmental variable completely explains the diversity or community structure. However, the Gulf may have two alternate states with respect to biodiversity and community structure.

Bridgette Froeschke

Bridgette Froeschke, Ph.D.

Former Graduate Student

Dissertation

Bridgette Froeschke, Ph.D.

Office
Suite 314
Laura Payne, M.S.

Laura Payne, M.S.

Former Graduate Student

Thesis

Laura Payne, M.S.

Thesis Title: Evaluation of Large-Scale Movement Patterns of Spotted Seatrout (Cynoscion nebulosus) Using Acoustic Telemetry

Abstract: Recreational saltwater fishing is a multi-billion dollar industry in Texas, with spotted seatrout (Cynoscion nebulosus) being the most sought after game fish in Texas’ near-shore waters. Recently, spotted seatrout population and spawning stock biomass declines prompted regionalized management strategies within Texas waters. Effective fishery management requires an understanding of movement patterns of managed species; although little is known about migratory patterns and residency times. Spotted seatrout are presumed to be estuarine resident with limited movement outside of natal estuaries. Anecdotal information suggests that spotted seatrout migrate from near-shore waters into bays to spawn and that these migratory fish may sustain populations of spotted seatrout within the Laguna Madre system. To further explore spotted seatrout movement patterns both laboratory tagging trials and acoustic tracking technology was employed to investigate movement patterns on a large-scale. A preliminary laboratory study was performed to determine the most effective surgery technique and suture material when implanting acoustic transmitters. Six treatment groups were used to investigate two incision locations (midline and off-midline) and three suture materials (braided, monofilament, and staples). Based on survival, tag retention, and healing scores, these results showed that the size of the fish as opposed to incision location or suture material had the most influence on tagging success. Following surgical trials, a total of 81 spotted seatrout greater than 400 mm TL were captured via hook and line between 8 December 2009 and 20 October 2010 and implanted with acoustic tags: 31 within bay waters, 30 fish from surf zones, and 20 live-release tournament fish. Movements were monitored with an array of 24 stationary receivers strategically placed between Port Aransas and Port Mansfield inlets. We found an overall minimal survival rate of 70% between angler recaptures and receiver detections. Many long distance travels were recorded and movement patterns varied greatly. Seventy-five percent of fish tagged in surf waters were detected on our receivers in tidal inlets, and two fish from the Upper Laguna Madre were detected leaving the Laguna into CC Bay. These data suggest Gulf-bay and inter-bay mixing of spotted seatrout populations. The high percentage of angler recaptures validates previous studies that determined catch-and-release practices are viable to help maintain healthy fish stocks. These data will be useful for fisheries managers to evaluate regionalized management tactics to further improve management of spotted seatrout in Texas.

Jason Williams

Jason Williams, M.S.

Research Specialist II

Thesis

Jason Williams, M.S.

Jason Williams is a Research Specialist for the Center for Sportfish Science and Conservation, where he specializes in larval fish ecology, GIS, and leads inshore and offshore field operations for the Center.

After graduating with his bachelor’s degree in ecology, evolution and conservation from the University of Texas at Austin, he moved to Port Aransas, ready to pursue a life in and around the water. Jason worked for six years as a lab tech in the University of Texas Marine Science Institute’s larval fish ecology lab before enrolling in the Masters of Biology program at Texas A&M Corpus Christi in 2008. There, under the guidance of Dr. Greg Stunz, he studied the effects of seagrass fragmentation on local marine life and joined the Harte Research Institute’s staff full time in 2011.

Office
Suite 311
Email
jason.williams@tamucc.edu
John Froeschke

John Froeschke, Ph.D.

Former Graduate Student

Dissertation

John Froeschke, Ph.D.

Dissertation Title: Defining Essential Fish Habitat: The Influence of Life History,  Biotic, and Abiotic Factors

Abstract: The world’s fisheries have been the subject of much recent concern due to dramatic declines in their abundance, and have continued despite increased single-species management of many harvested species. As a result, management of marine ecosystems is shifting toward an ecosystem-based approach, where the importance of interactions among physical, biological, and human components of the system is recognized. However, ecosystem-based approaches rely on our ability to efficiently and effectively assess critical habitat necessary for ecosystem sustainability; for fisheries, this is known as Essential Fish Habitat (EFH). Currently, few marine systems have adequate information about EFH to implement ecosystem-based approaches to resource management, despite federal mandates to delineate and characterize these areas. The paucity of data is particularly absent beyond typical habitat-density assessments. Undoubtedly, what makes a habitat essential is a variety of abiotic and biotic interactions, but these types of information for even the most important fisheries have seldom if ever been evaluated. This dissertation research seeks to combine several aspects of Essential Fish Habitat, specifically, the influences of abiotic, biotic, and life history on habitat use of estuarine and coastal fishes. Research was carried out using a multi-disciplinary approach integrating biological and physical sciences to improve our understanding of habitat requirements for ecologically and economically important species.

The primary goal of this dissertation was to assess environmental and biological factors that influence the quality of fish habitat. However, applying general habitat requirements for marine fishes that exhibit widely diverse and complex life history strategies can be particularly problematic. Thus, representative species from highly migratory species (sharks) and both estuarine dependent and estuarine-resident teleosts were assessed to make predictions concerning EFH across a broad spectrum of life history strategies.

Using a long-term fisheries independent dataset, I conducted the first experimental test of the 'shark nursery area concept' and identified areas along Texas’ central coast as shark nursery habitat. This concept was further investigated by developing spatially-explicit estuarine habitat use models based on environmental conditions for three coastal shark species: bull (Carcharhinus leucas), blacktip (Carcharhinus limbatus), and bonnethead (Sphyrna tiburo) to delineate within-bay patterns of habitat usage and to determine relationships between environmental predictors and shark distribution. Status and trends of shark species in the nearshore Gulf of Mexico were also assessed using historical and current fishery-dependent data. From 1973 to 1986 and 2008 to 2009, I examined shark capture logs from recreational shark anglers on the Texas coast to characterize catch patterns, species composition, and temporal patterns of coastal shark abundance in this region as no data currently exist and the population status for sharks in this region is uncertain.

Habitat selection and movement patterns were also investigated for representative species exhibiting a more typical estuarine-dependent life cycle using experimental mesocosms and otolith stable isotope analyses. Mesocosm experiments examined the relative influence of dissolved oxygen concentration, food abundance, habitat complexity, and predator density on habitat selection patterns of juvenile pinfish (Lagodon rhomboides) and Atlantic croaker (Micropogonias undulatus). Results from experimental mesocosoms indicate that for young (or small) fishes, the influence of predator density may be the primary determinant of fish habitat use. However other factors including dissolved oxygen or habitat type also influence habitat selection, often in complex or interactive patterns.

Connectivity among essential areas is also recognized as a critical factor influencing population dynamics of aquatic organisms. Spotted seatrout (Cynoscion nebulosus) is an economically and ecologically important species in the Gulf of Mexico and supports large recreational fisheries throughout its range. However, regional declines of spotted seatrout stocks on the south Texas coast have prompted concerns about the connectivity of fish among management regions in this area and the effectiveness of recently implemented regional management for this species, but essential habitat and connectivity among populations hinders proper management To examine connectivity of trout populations over a large scale, stable carbon (δ13C) and oxygen (δ18O) isotopes in otoliths were used to assess the degree of exchange of adult spotted seatrout from five regions on the south Texas coast. Cross-validated classification success to five regions of the coast was 64% and indicated that mixing was most likely between adjacent regions although some long-term migrations likely occur.

Isis Dominguez Gain

Isis Dominguez Gain, M.S.

Former Graduate Student

Thesis

Isis Dominguez Gain, M.S.

Thesis Title: Oyster Reefs as Nekton Habit in Estuarine Ecosystems

Abstract: Oyster reefs are important components of marine ecosystems and function as essential habitat for many estuarine species. However, few studies have focused on the interaction and synergy of oyster reefs with other estuarine habitat types (e.g., seagrasses, marsh). This research was designed to characterize the macrofaunal community associated with shallow water, intertidal oyster reefs. I examined the functional habitat relationships of oyster reefs and the effects of structural complexity, spatial synergy, and predator influence on habitat selection. Two sites in Corpus Christi Bay, Texas, were sampled using a throw-trap sampler. Replicate, intertidal oyster reef plots, marsh edge, and seagrass habitats were compared. Results showed higher overall densities of nekton and benthic crustaceans on oyster reefs compared to seagrass and marsh edge habitat types. Oyster reefs supported a distinctive community of nekton and benthic crustaceans. The spatial relationships of habitat types was evaluated by sampling oyster reef adjacent to mud bottom, oyster reef adjacent to seagrass, and oyster reef adjacent to marsh edge. Highest densities were collected on oyster reefs near seagrass and mud bottom. Predator exclusion cages were used to evaluate community differences on oyster reefs with and without predation pressure. Differences in nekton densities were found among predator exclusion treatments during fall. To evaluate the role of structural complexity on oyster reefs, habitat selection of a fish, juvenile red drum (Sciaenops ocellatus), and a crustacean, brown shrimp (Farfantepaneaus aztecus), were examined using experimental mesocosms. Selection patterns were also evaluated in the presence and absence of large predators, pinfish (Lagodon rhomboides). Red drum habitat selection was not influenced by structured habitats in the absence of a predator. However, when exposed to predators, red drum showed clear selection patterns for more structured, complex habitat. Brown shrimp were not exposed to predators, and did not show a strong selection pattern for more or less complex reefs. These results suggest that the structurally complex estuarine habitat provided by oyster reef may function similarly to seagrass or marsh edge habitat types and may provide a refuge from predation for some fish and crustaceans.

 

Jenny Oakley

Jenny Oakley, M.S.

Former Graduate Student

Thesis

Jenny Oakley, M.S.

Thesis Title: Spatiotemporal and Habitat-Mediated Food Web Dynamics in Lavaca Bay, Texas

Abstract: Examining food web dynamics is important for understanding ecosystem-wide interactions in marine systems. The purpose of this study was to examine spatial and temporal trophic structure in subtidal oyster reefs as compared to other estuarine habitat types (i.e., intertidal marsh and non-vegetated bottom) in Lavaca Bay, Texas. This study also integrated spatiotemporal food web analysis by combining stomach content analysis and stable isotope techniques. Sampling occurred seasonally from July 2006 to April 2007. Samples of macroinvertebrates and fishes were collected using epi-benthic sleds, modified epi-benthic sleds, and gill nets for both stomach content and stable isotope analyses. In addition, samples of vegetation, particulate organic matter, and benthic organic matter were collected for stable isotope analysis. The Lavaca Bay food web is dynamic supporting a variety of organisms representing trophic levels from primary producers to tertiary consumers. Stomach content analysis showed that economically important species, such as Brevoortia patronus and penaeid shrimp, were not only exceptionally abundant within the estuary, but also have a high index of relative importance as prey items. The distribution of trophic levels among habitat types varied, with the subtidal oyster reef habitat supporting a higher mean trophic level as compared to the marsh and non-vegetated habitats. Subtidal oyster reef was the only habitat that supported both large numbers of low trophic level consumers and apex predators. Spatially, the lower region of the bay supports a more robust food web with comparably more links. This could be due to many factors such as variation in fresh water inflow (i.e. salinity), available habitat types, and proximity to a tidal inlet. Temporally, the summer and fall food webs of Lavaca Bay support a higher trophic level food web with more secondary and tertiary consumers and available links. Combining both stomach content and stable isotope methods provides detailed assessments of food web dynamics in these systems, especially for lower trophic level species. This information is particularly timely because oyster reef coverage in the Lavaca Bay system, and many others, have been diminishing in recent years, and alterations to this habitat type may have wideranging impacts. Thus, this study provides information on the ecological roles of subtidal oyster reefs and aids in planning for improved management ensuring the persistence of these reefs.

Office
Suite 314
Amanda Bushon

Amanda Bushon, M.S.

Former Student

Thesis

Amanda Bushon, M.S.

Thesis Title: Recruitment, Spatial Distribution, and Fine-Scale Movement Patterns of Estuarine Dependent Species Through Tidal Inlets in Texas

Abstract: Information on geographical recruitment patterns of estuarine-dependent fish is critical to understanding their ecology. Red drum (Sciaenops ocellatus), southern flounder (Paralichthys lethostigma), blue crab (Callinectes sapidus), and penaeid shrimp (Farfantepenaeus aztecus, F. duorarum, Litopenaeus setiferus) use estuaries as nurseries; therefore, they make ideal model species for this study.

Estuaries are considered nurseries in that they provide plentiful food supplies for growth and structured habitat types for protection from predators. While generalities concerning estuarine recruitment dynamics are somewhat understood, spatial recruitment patterns from an inlet are unknown.

The purpose of this research is to characterize how far red drum, southern flounder, blue crabs, and penaeid shrimp disperse from an inlet before settling into a nursery habitat (e.g., seagrass meadows) and to examine the effects of a new inlet on recruitment. Packery Channel is a natural tidal inlet that connects Corpus Christi Bay to the Gulf of Mexico and was closed since the 1930’s until recently opened.

This is a unique opportunity to study recruitment patterns in an area that was previously inaccessible to newly settling fishes and crustaceans. On a smaller scale, I also assessed the effect of artificial habitat and corridors within tidal inlets on red drum recruitment dynamics as well as fine-scale movement patterns of newly settled wild and hatcheryreared red drum using mark and recapture techniques.

To examine the effect of distance and the effect of opening Packery Channel on the recruitment of juvenile fishes and decapod crustaceans, I evaluated densities of juvenile red drum, southern flounder, blue crabs, and penaeid shrimp in seagrass beds of Halodule wrightii at varying distances from Aransas Pass and Packery Channel pre- and post-opening. I found that densities of these species were repeatedly higher at sites closest to the inlet, suggesting that high levels of recruitment occur at the first extensive seagrass meadows new recruits encounter.

Prior to the opening of Packery Channel, newly settled individuals typically did not occur in areas near Packery Channel. However, after the opening of Packery Channel, densities of small individuals of all species were high in these areas suggesting they are recruiting through the new inlet. Once fully opened, the Packery Channel could have a great impact on the densities of recruiting nekton in the upper Laguna Madre. I also examined the role that settlement habitat within an inlet plays on recruitment to seagrass beds within the bay.

My results suggest that seagrass beds within the tidal inlet do not affect the densities of red drum within a bay and that these fish are not using the habitat in the channel as corridors. I also evaluated the use of visible implant elastomer (VIE) for mark and recapture studies on juvenile red drum and performed a preliminary study on the finescale movement patterns of red drum within a seagrass bed. I found that VIE is an effective method for marking small red drum, and they may have a much larger dispersal potential than previously suspected.

Overall, seagrass beds nearest to the inlet appear to be the most important for settling juvenile fish and crustaceans, and the opening of Packery Channel has allowed access to habitats in upper Laguna Madre that were previously inaccessible to newly settling juveniles, possibly enhancing fisheries productivity in that area.

Office
Suite 314
Megan Robillard

Megan Robillard, M.S.

Program Manager

Thesis

Megan Robillard, M.S.

Megan Robillard is a fisheries biologist and Program Manager for the Center for Sportfish Science and Conservation, managing overall program operations and research. 

Megan was raised in Minnesota and received her bachelor’s degree in biology from St. Cloud State University. In 2004, she headed south to enroll in the Master of Science program at Texas A&M University-Corpus Christi. In her thesis work, Megan studied the newly opened Packery Channel tidal inlet that separates Padre and Mustang islands, evaluating its impact on juvenile sportfish seeking access to important nursery habitats in the marshes and seagrass of the Laguna Madre.

Since 2006, Megan has been a full-time Harte Institute researcher, acquiring experience in a broad range of areas from juvenile fishes in the estuary to large, prized, highly-migratory sportfish in the Gulf’s offshore waters.

Suraida Nañez-James, M.S.

Suraida Nañez-James, M.S.

Former Graduate Student

Thesis

Suraida Nañez-James, M.S.

Thesis Title: Identification and Characterization of Nursery Habitat For Juvenile Southern Flounder, Paralichthys lethostigma, in Aransas Bay, Texas

Abstract: Southern flounder Paralichthys lethostigma populations in Texas have been in steady decline over the last 25 years. Despite the economic importance of this species, little is known about their juvenile habitat requirements. The goal of this study was to determine temporal and spatial habitat use patterns for juvenile southern flounder and characterize these patterns in terms of habitat selection. Monthly sampling was conducted over a two-year recruitment period (January-April 2004, and January-March 2005) in the Aransas-Copano estuaries on the Texas coast. The bay complex was divided into three zones based on a decreasing salinity gradient and increasing distances from Aransas Pass. Replicate estuarine habitat types were sampled in each of these zones. Triplicate samples were taken using a beam trawl in different habitats, seagrass (Halodule wrightii), marsh (Spartina alterniflora), and open-water (nonvegetated bottom), at each of nine sampling sites within each zone. Catch data indicated distinct habitat distribution patterns. Highest densities occurred closest to Aransas Pass in vegetated, sandy bottom areas. Lowest densities occurred in nonvegetated, muddy bottom areas farthest from the pass. Habitat selection patterns for southern flounder were examined using experimental mesocosms. Since wild fish occurred at low densities, hatchery-reared fish were used. Four common natural habitat types were simulated in twelve 38-L glass tanks: (1) oyster reef, (2) salt marsh (Spartina alterniflora) (3) seagrass (Halodule wrightii), and (4) nonvegetated, sand bottom. Mesocosms were divided in half with each containing a different constructed habitat type. Selection patterns were compared for all possible combinations of habitat pairings. Habitat selection experiments showed juvenile southern flounder selected nonvegetated sand bottom over structured habitat (vegetated and oyster habitats) and selected seagrass over all other structured habitats when nonvegetated sand bottom was not available for selection. Habitat use patterns show vegetated habitats near a tidal inlet serve as important nursery grounds for juvenile southern flounder. Habitat selection experiments indicated juvenile flounder select to settle in nonvegetated sand bottom habitats near or in vegetated areas. A 25- year bag seine data set from Texas Parks and Wildlife Department (TPWD) was analyzed to assess long-term spatial and temporal patterns. Bag seine data were interpreted using Arc GIS 9.1 to calculate southern flounder catch per hectare (catch per unit effort) during the peak recruitment period (December-April). Data maps showed high numbers of flounder near tidal inlets, with the highest number of flounder collected during April. These observations were similar to field observations and support the importance of vegetated habitats near tidal passes as nursery areas.

Jason James

Jason James, M.S.

Former Graduate Student

Thesis

Jason James, M.S.

Thesis Title: Catch-and-Release Mortality of Spotted Seatrout

Abstract: The spotted seatrout (Cynoscion nebulosus) is a highly sought-after marine sportfish along the Gulf Coast and in Texas. Despite the apparent abundance of spotted seatrout, increasing fishing pressure has raised concerns over its sustainability, particularly as it relates to the larger individuals. As a result, a maximum size limit management regulation has been enacted that requires the release of larger individuals. This strategy will work only if the fish survive post-release. The purpose of this study was to estimate catch-and-release mortality associated with hook-and-line captured spotted seatrout by recreational anglers as a function of anatomical hooking location, season, and tournament-related mortality. From July 2004 to June 2005, a total of 479 spotted seatrout ranging from 220 – 555 mm TL were captured by hook-and-line in Aransas and Corpus Christi Bays and maintained in replicated 3.5-m3 field enclosures for 72 h. Overall mortality for the experimental studies was 19%. For anatomical studies, hooking location was assigned to four body regions: mouth, gills, esophagus, and external. Study results suggest anatomical hooking location is a major factor influencing spotted seatrout mortality. Fish hooked in the gills and esophagus had mortality rates of 75% and 95%, respectively, whereas fish hooked external and in the mouth had mortality rates of 8% and 10%, respectively. A significant relationship was found between season and catch-and-release mortality of spotted seatrout with higher mortality rates in spring and summer months than fall and winter. Trends were observed when examining monthly mortality rates and environmental conditions. These trends showed significant relationships with water temperature, dissolved oxygen, and salinity. Data was also collected on 1,373 spotted seatrout from nine live-release tournaments. Overall tournament mortality was 23% with initial and delayed mortality rates of 11% and 14%, respectively. To assess delayed long-term tournament survival, fish were maintained in a laboratory holding facility for up to 30 d. These results reveal a high percentage (>80%) of tournament caught fish survive post-release. No significant relationship was observed between size class and percent mortality of fish caught during the seasonal study or tournament-caught fish held for long-term studies. A tagging study was conducted to assess movement and long-term, post-release survival of spotted seatrout. Seven hundred twenty-six spotted seatrout were tagged and released. Tag recovery rate was 1.2% with a total of nine fish recaptured with variable movement patterns. Overall, relatively low mortality rates for hook-and-line captured spotted seatrout were observed suggesting current catch-and-release management regulations in the spotted seatrout fishery are a viable management strategy.

Todd Neahr

Todd Neahr, M.S.

Former Graduate Student

Thesis

Todd Neahr, M.S.

Thesis Title: Habitat Use Patterns of Newly-Settled Spotted Seatrout Cynoscion nebulosus in Gulf Coast Estuaries

Abstract: Estuaries are notable for high diversity making them one of the most productive marine ecosystems. Many fish species of economic importance use estuaries during at least one phase of their life cycle. Despite the recognition of the importance of habitat within estuaries, there are considerable gaps in knowledge concerning the specific patterns of habitat use for many important fishery species including the spotted seatrout Cynoscion nebulosus. The primary goal of this study was to examine the habitat use patterns of newly-settled spotted seatrout in three Texas Coastal Bend bays. In each bay, newly-settled trout were sampled using an epibenthic sled in three different habitat types: seagrass (Halodule wrightii), marsh edge (Spartina alterniflora), and nonvegetated bottom. These results suggest bay specific patterns of habitat use with the highest juvenile spotted seatrout densities occurring in seagrass meadows. A secondary goal was to examine spotted seatrout habitat use in marsh dominated bay systems from Barataria Bay, Louisiana to the seagrass dominated systems of the Lower Laguna Madre, Texas using data provided by NOAA Fisheries Service, Galveston, Texas. The NOAA Fisheries Service determined nekton abundance using enclosure samplers along the Gulf Coast from 1982 to 1997. These data show that in areas with no submerged aquatic vegetation, highest densities of juvenile spotted seatrout occurred at the marsh edge open water interface. Spotted seatrout habitat selection was examined using experimental mesocosms. These trials were conducted for both hatchery-reared and wild-caught spotted seatrout by subjecting them to selection trials using every possible pair-wise combination of common estuarine habitat types. The general pattern was that hatcheryreared and wild-caught mesocosm fish showed selection patterns for structured habitats (oyster reef, seagrass beds and marsh edge) over nonvegetated bottom, but selection among structured habitat types did not show strong patterns. Size related habitat selection patterns were also observed, where habitat selection was not as apparent for larger individuals. These results suggest that structured habitat types, particularly seagrass meadows and marshes, are important nursery habitat for juvenile spotted seatrout and strong habitat selection patterns may diminish as fish grow.

 

Dana Burfeind

Dana Burfeind, Ph.D.

Former Graduate Student

Thesis

Dana Burfeind, Ph.D.

Thesis Title: Effects of Propellor Scarring on Seagrass-Associated Fauna

Abstract: Seagrasses play a critical role in the function and structure of coastal ecosystems, and they are an important habitat for a variety of marine organisms. Damage to seagrass beds from boat propellers is significant in many areas. Recognizing the need to protect this valuable habitat, three voluntary no motor zones were established in Redfish Bay, Texas. This study was designed to test the effectiveness of these protected areas and to assess the impact of propeller scarring on nekton. To examine compliance, I made visual observations of boat activity in these areas. My data showed zero boater compliance in the voluntary no motor zones. I characterized the effects of the propeller scarring on seagrass-associated fauna by: (1) comparing measures of fish and decapod crustacean at three distinct scarring intensities to unscarred sites; and (2) characterizing the functional relationships size, mortality; growth rate to scarring intensity. I selected 10 replicate (10 x 25m quadrats) sites representing three distinct scarring intensities: reference (0%), low (5% or less), moderate (5-15%), and severe (>15%). Sites were sampled in 2003-2004 for nekton during 4 seasons (summer, fall, winter, and spring) using epibenthic sleds. Growth rates of selected fauna were examined using field enclosure experiments and otolith microstructure analysis. My results suggest that even severe (>15%) propeller scarring may not affect density patterns, mean size, or mortality of the organisms collected. Otolith microstructure analysis on pinfish (Lagodon rhomboides) indicated no difference in growth rate at various scarring intensities; however, field growth enclosure experiments with white shrimp (Litopenaeus setiferus) showed significantly lower growth in highly scarred areas than reference sites. These results suggest the need for further study at different spatial scales and at higher scarring intensities to determine at what level propeller scars affect the functionality of seagrass.