CFI Research

CFI faculty and staff conduct research on a wide variety of topics related to coastal fisheries resources. Basic and applied research projects are funded by Federal and State government agencies and private foundations to address environmental issues important to coastal resources and fish. Several recent projects are highlighted below.

	Age and Growth The Age and Growth Laboratory of the Coastal Fisheries Institute was established in 1985 to develop age and growth information about important fish species in the northern Gulf of Mexico. Since its establishment, the laboratory has processed otoliths of over forty thousand fish from variety of species (mullet, red drum, black drum, trout, amberjack, cobia, swordfish, tuna, sheepshead, red snapper, vermillion snapper, and others) and the resultant data have been used in the development of both state and federal fishery management plans.
	Hydroacoustics / Artificial Reef Program Research is currently underway studying the effects of oil and gas platforms on fish populations and their function as artificial reefs. This work is being conducted using state of the art hydroacoustic and remotely operated underwater vehicle (ROV) technologies to estimate the species composition, abundance and size distribution of fish at these defacto artificial reefs. Long term studies have been conducted or are in progress at various sites in the Gulf of Mexico with the goals of determining what affects the abundance of fishes at these structures and how they function as artificial reefs.
	The CFI Ichthyoplankton Lab Located in Tiger Stadium, The Ichthyoplankton lab is responsible for processing plankton samples and the identification of larval and juvenile fishes of the northern Gulf, as well as zooplankton. Since its establishment in 1981, the Icthyoplankton Lab has identified tens of thousands of larvae for a variety of state and federally funded research projects. Current research, headed by Dr. Richard F. Shaw and funded by the Minerals Management Service, focuses on determining the abundance, distribution, and seasonality of larval and juvenile fish at offshore petroleum platforms near the Mississippi River Delta. Due to the dearth of hard bottom in the northern Gulf, the platforms may have a significant function as habitat for postlarval and juvenile fish, acting as nursery grounds and/or refugia.
	Reproductive Biology The fish Reproductive Biology Laboratory of the Coastal Fisheries Institute was established in 1985 to develop reproductive biology information about important fish species in the northern Gulf of Mexico. Like the Age and Growth Lab, the Reproductive Biology Lab has processed thousands of fish of a variety of species and the resultant data have been used in the development of both state and federal fishery management plans. The personnel associated with this laboratory have established reproductive analysis techniques that have become routine in many other laboratories around the world.
	Otolith Microchemistry An emergent field in fisheries biology is the use of chemical analyses of otoliths to infer life history characteristics of fishes. In our laboratory, personnel are involved with several projects utilizing otolith microchemistry as a tool to examine the population ecology of northern Gulf of Mexico fishes. Among these projects are 1) discriminating among red snapper, Lutjanus campechanus, northern Gulf of Mexico continental shelf nursery habitats with elemental signatures of age-0 fish, 2) discriminating among red drum, Sciaenops ocelatus, natal estuaries in north central Gulf of Mexico with otolith microchemical fingerprints of juvenile fish, and 3) discriminating among south Atlantic and Gulf of Mexico king mackerel, Scomberomorus cavalla, stocks with minor and trace elements detected in whole adult otoliths.
	A High-Resolution Digital Imaging System Optical sensing systems are one of the most promising new technologies for measuring the fine-scale (cm to km) distributions of small organisms in the sea. CFI researchers are developing a vertically-profiling, high-resolution digital imaging system capable of imaging zooplankton-sized particles in water depths down to 250 meters. This system will generate profiles of the concentration, composition, and size of zooplankton in their natural environment. Spatial statistical methods are then used to create three dimensional visualizations of the imaged data. Results will provide naval and civilian oceanographers with a powerful tool for probing and visualizing the distributions of living and non-living zooplankton-size particles.
	Zebra Mussels in the Lower Mississippi River Zebra mussels, an exotic intruder first found in the Great Lakes, are now found in the lower Mississippi River. Zebra mussels can fundamentally alter an aquatic system due to their extremely rapid population growth resulting in extensive removal of particles in water by their feeding. CFI researchers are measuring the growth and mortality of zebra mussels in the field to establish their habitat requirements in the lower Mississippi River, which is the southernmost extreme of their current range. Relating the gathered data to observed recruitment and settlement patterns will provide important information on the effectiveness of different methods for zebra mussel control as they continue their invasion southward.
	Stock Identification of Red Snapper in the Gulf of Mexico Management of the red snapper fishery assumes there is one stock in the Gulf of Mexico. In a large, collaborative effort with the University of South Alabama and Texas A&M University, CFI researchers are performing the first large scale test of the one stock hypothesis. Comparative analyses of DNA, otolith microchemistry, and growth and reproductive rates of red snapper from different locations will be used to determine the number of discrete stocks inhabiting the western Gulf of Mexico. Such findings could profoundly affect the management of red snapper.
	Effects of Endocrine Disruptor Chemicals on Estuarine Fish Populations Very low concentrations of endocrine disruptor chemicals can change the hormonal balances in fish and other taxa. These changes in hormones have sublethal effects on fish, such as slowed escape response to predators and reduced reproductive capabilities. CFI researchers, in collaboration with several other universities, have embarked on a study that will use a variety of computer modeling techniques to scale up laboratory assays of endocrine chemical effects on fish to long-term, population-level responses.
	Shrimp Population Dynamics and Fishery in the Gulf of Mexico Brown shrimp landings in the Gulf of Mexico display substantial inter-annual variability. CFI researchers are using regression and simulation modeling techniques to better understand how environmental and biological factors affect shrimp recruitment. Regression and other statistical methods are being applied to nearly 30 years of life stage abundances and environmental variables to determine factors important in affecting survival over the entire life cycle. Simulation modeling is being used to understand the role of marsh habitat in affecting the survival and growth of young shrimp. Results can be used to improve shrimp fisheries management and quantify the role of marsh habitat in shrimp population dynamics.
	Economic Analysis of Private Market Wetland Values in Coastal Louisiana More than five million acres of wetlands, or about 40% of the nation's total, are contained in Louisiana's coastal zone. Approximately 80% of this acreage is privately owned. Current wetland loss, primarily through the processes of erosion and subsidence, is estimated to approach 35 thousand acres annually. CFI researchers are developing a set of economic instruments which will encourage private landowners to maintain their wetland properties to benefit the public. The stability of ownership and the characteristics of wetlands that influence their market value are being quantitatively analyzed to develop public policy that will encourage private landowners to maintain wetland properties.
	Shark Nursery Areas in the Gulf of Mexico Sharks are long-lived and are highly migratory. Atlantic shark populations are currently threatened because of over-fishing and a lack of basic biological data. CFI researchers are presently quantifying the mortality rates, ages, growth rates, and maturity status of sampled sharks off of Louisiana's coast. Results will document the nursery role of Gulf of Mexico coastal waters, and will provide critical information needed for the effective management of this top predator.
	Sub-lethal Effects of Petroleum Additives on Fishes Development of deepwater petroleum resources can result in the exposure of commercial, sport, and forage fishes to chemicals. Chronic low-level exposure of fishes to dissolved contaminates may not cause them to die outright, but they may exhibit changes in performance that ultimately lead to reduced fitness. CFI researchers and colleagues from other universities are using an experimental approach to study the effects of sub-lethal contaminant exposure on the swimming abilities of three common fishes. Consequent changes in whole animal performances are relevant to ecological situations such as predator-prey interactions and ultimately to chances for individual survival and reproduction.