Age and Growth of the Sandbar Shark (Carcharhinus plumbeus) from the Northern Gulf of Mexico and the Western North Atlantic Ocean

Age and growth analysis of the sandbar shark, Carcharhinus plumbeus, from the northern Gulf of Mexico and western North Atlantic Ocean was completed with vertebral samples (n = 1,194). Three parameter von Bertalanffy growth curves were run for male and female sandbar sharks separately, and growth parameters were estimated: theoretical maximum length (L∞) = 172.9 ± 1.3 cm straight-line fork length [FL], growth coefficient (k) = 0.15 ± 0.01 yr-1, x-intercept (t0) = 22.3 ± 0.2 SE (male); and L∞ = 181.2 ± 1.5 cm FL, k = 0.12 ± 0.01 yr-1, t0 = 23.1 ± 0.2 SE (female). The oldest sandbar shark was a 27-yr-old female, and the oldest male was 22 yr old. The age and growth parameters estimated during this study differed from those in previous studies. The differences in the age and growth parameters may indicate growth overfishing, or they may be due to the bias in sampling from a fishery that targets a limited size range of sharks

Temporal and Spatial Distribution of Finfish Bycatch in the U.S. Atlantic Bottom Longline Shark Fishery

Bycatch in U.S. fisheries has become an increasingly important issue to both fisheries managers and the public, owing to the wide range of marine resources that can be involved. From 2002 to 2006, the Commercial Shark Fishery Observer Program (CSFOP) and the Shark Bottom Longline Observer Program (SBLOP) collected data on catch and bycatch caught on randomly selected vessels of the U.S. Atlantic shark bottom longline fishery. Three subregions (eastern Gulf of Mexico, South Atlantic, Mid-Atlantic Bight), five years (2002–06), four hook types (small, medium, large, and other), seven depth ranges (300 m), and eight broad taxonomic categories (e.g. Selachimorpha, Batoidea, Serranidae, etc.) were used in the analyses. Results indicated that the majority of bycatch (number) was caught in the eastern Gulf of Mexico and that the Selachimorpha taxon category made up over 90% of the total bycatch. The factors year followed by depth were the most common significant factors affecting bycatch