Influences of Artificial Reefs on Juvenile Red Snapper along the Mississippi Gulf Coast

Abstract

Red Snapper Lutjanus campechanus represent one of the more economically important fisheries in the northern Gulf of Mexico; as such, Red Snapper abundance has decreased dramatically in the past two decades. The use of artificial reefs could aid in the rehabilitation of Red Snapper stocks by providing refuge for juveniles and a place of foraging and recruitment. A study was initiated to determine the effectiveness of different artificial reef distribution patterns in attracting and sustaining juvenile Red Snapper in the northern Gulf of Mexico. Fish traps (0.97 m long; 0.64 m high; funnel mouth size = 175×115 mm) were used to collect Red Snapper (<406 mm TL) that were associated with pyramid‐shaped artificial reef structures (3.7‐m triangular base; 2.4‐m height; 3.2 metric tons) to evaluate two reef distribution designs: (1) five closely spaced pyramid units (“clumped” pattern) and (2) five closely spaced pyramids plus two sets of two pyramids at 30.5, 61.0, or 91.5 m from the five pyramids (“outlier” pattern). In 26 sampling trips, 927 Red Snapper were captured. Catch per unit effort (number of fish/trap soak‐hour) did not differ significantly among artificial reef patterns (P = 0.396). Red Snapper TLs differed significantly among patterns (P = 0.005), with the largest mean TL (235 mm; SE = 5.14) occurring at the outlier pattern with 61.0‐m spacing. Results from this study indicate that reef spacing and horizontal extension are important factors to consider when designing an artificial reef program, especially those that target juvenile Red Snapper.Received February 2, 2012; accepted September 26, 2012

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