Population genetics of the nurse shark (Ginglymostoma cirratum) in the western Atlantic

Abstract

The nurse shark, Ginglymostoma cirratum, inhabits shallow, tropical, and subtropical waters in the Atlantic and the eastern Pacific. Unlike many other species of sharks, nurse sharks are remarkably sedentary. We assayed the mitochondrial control region and eight microsatellite loci from individuals collected primarily in the western Atlantic to estimate the degree of population subdivision. Two individuals from the eastern Atlantic and one from the Pacific coast of Panama also were genotyped. Overall, the mtDNA haplotype (h = 48 ± 5%) and nucleotide (π = 0. 08 ± 0. 06%) diversities were low. The microsatellite data mirror the mitochondrial results with the average number of alleles(N̄ =9)an..