An Evaluation of a Reduced Bar Spacing Turtle Excluder Device in the U.S Gulf of Mexico offshore Shrimp Trawl Fishery

Shrimp are the most economically valuable internationally-traded seafood commodity, and wild-caught, trawled shrimp make up almost half of the ~6.6 million metric tons of annual global production. Shrimp trawling is responsible for one-third of the world’s total fisheries bycatch, leading many to consider shrimp trawling to be the single most destructive fishing practice in the world. Though the bycatch of large marine animals can be significantly reduced by use of turtle excluder devices (TEDs) on shrimp trawls, current TED designs are ineffective at reducing the capture of smaller organisms which represent a large portion of the total bycatch. To further reduce bycatch in the United States Gulf of Mexico shrimp trawl fleet, a variety of bycatch reduction devices (BRDs) are currently being used in conjunction with TEDs. I evaluated the efficiency of a new TED design, intended to reduce bycatch and maintain target shrimp catch. The new TED model is characterized by 5-cm spacing between flat bars, as opposed to the current industry standard of 10-cm spacing between round bars. Comparative towing experiments under standard commercial shrimp trawling operations in waters off of Georgia, Texas and Mississippi during the summer of 2012 demonstrated shrimp losses or gains of -4.32%, +6.07%, -1.58% respectively and an overall reduction in the capture weight of sharks (41.1-99.9%), rays and skates (76.5-93.4%) and horseshoe crabs (100%). These experiments were limited in time and space, and therefore not fully representative of fishing conditions throughout the year, but this study demonstrates the new TED’s effect on the catch rates of target shrimp and bycatch. This thesis research should lead to a broader understanding of the benefits of using reduced spacing flat bar TEDs in the U.S. shrimp trawl industry

Knowledge Modelling and Learning through Cognitive Networks

One of the most promising developments in modelling knowledge is cognitive network science, which aims to investigate cognitive phenomena driven by the networked, associative organization of knowledge. For example, investigating the structure of semantic memory via semantic networks has illuminated how memory recall patterns influence phenomena such as creativity, memory search, learning, and more generally, knowledge acquisition, exploration, and exploitation. In parallel, neural network models for artificial intelligence (AI) are also becoming more widespread as inferential models for understanding which features drive language-related phenomena such as meaning reconstruction, stance detection, and emotional profiling. Whereas cognitive networks map explicitly which entities engage in associative relationships, neural networks perform an implicit mapping of correlations in cognitive data as weights, obtained after training over labelled data and whose interpretation is not immediately evident to the experimenter. This book aims to bring together quantitative, innovative research that focuses on modelling knowledge through cognitive and neural networks to gain insight into mechanisms driving cognitive processes related to knowledge structuring, exploration, and learning. The book comprises a variety of publication types, including reviews and theoretical papers, empirical research, computational modelling, and big data analysis. All papers here share a commonality: they demonstrate how the application of network science and AI can extend and broaden cognitive science in ways that traditional approaches cannot

Gulf States Marine Fisheries Commission

Headquartered in Ocean Springs, Mississippi, the GSMFC is an organization of the five states (Texas, Louisiana, Mississippi, Alabama, and Florida), whose coastal waters are the Gulf of Mexico. Objective is the conservation, development, and full utilization of the fishery resources of the Gulf, to provide food, employment, income, and recreation. Site features information on Commission programs, publications, meetings, fishing and boating regulations, and area-specific issues. Educational levels: High school, General public

Habitats and Biota of the Gulf of Mexico: Before the Deepwater Horizon Oil Spill: Volume 1: Water Quality, Sediments, Sediment Contaminants, Oil and Gas Seeps, Coastal Habitats, Offshore Plankton and Benthos, and Shellfish

environmental management; marine; freshwater science