Efficacy and Feasibility of Alginate Bait for the Louisiana Commercial Blue Crab (Callinectes sapidus) Fishery

• Main Author: Clowes, ElizaBeth Lorraine
• Other Authors: Lively, Julie Anderson
• Format: Others
• Language: en
• Published: LSU 2016
• Subjects: Renewable Natural Resources
• Online Access: http://etd.lsu.edu/docs/available/etd-04062016-203518/

Louisiana leads all U.S. states in blue crab (Callinectes sapidus) landings, but high fuel and bait costs have hindered commercial fishing productivity of Louisiana in recent years. The primary baitfish, Atlantic menhaden (Brevoortia tyrannus), has steadily increased in price and decreased in availability, while crab prices remain low. To reduce costs for fishermen, an alternative bait was developed that incorporates shrimp waste into a semi-rigid alginate matrix. Lab testing and preliminary field tests show that shrimp-alginate bait may be a suitable alternative to menhaden for Louisiana crab fishermen. I evaluated bait performance by conducting field sampling to compare catch rates and longevity of standard baitfish and shrimp-alginate bait. I performed seasonal fishery-independent testing at three sites across Southern Louisiana from summer 2014 to spring 2015, and tested the bait on commercial crabbing boats throughout coastal Louisiana during peak crab season in 2015. Catch rates of shrimp-alginate were less than menhaden overall, however, bait performance changed with site and season, and did not significantly differ when I evaluated commercially relevant crab classes. Analysis of remaining bait quantity after fishing showed that shrimp-alginate remains intact as long, or longer, than standard baitfish during peak crab fishing from June through August. After testing shrimp-alginate bait in the field, I evaluated the economic feasibility of producing the bait with a partial budget supply line. With its current formulation, shrimp-alginate can only be produced at a cost lower than menhaden (currently $0.50/lb.) under optimal production scenarios, however, slight modifications that improve shelf life could dramatically decrease the cost of bait production. Findings from both field work and feasibility analysis show promise in the alternative shrimp-alginate bait with given improvements to catch rate efficacy and product storage.