Population Genetic Structure of Spotted Eagle Rays,Aetobatus narinari,off Sarasota, Florida and the Southeastern United States

Abstract

The Spotted Eagle Ray, Aetobatus narinari, is a semi-pelagic myliobatoid recognized as near threatened by the World Conservation Union. A decreasing population trend, K-selected life history, and primarily inshore, coastal habitat renders this species susceptible to over-exploitation by targeted fisheries, drift netting, and capture as bycatch. Recent molecular investigations and subsequent taxonomic recognition as a species complex have left a large deficiency in current knowledge of A. narinari and a complete absence of data concerning population structure and genetic health for the northwestern Atlantic Ocean. Our study is the first to examine fine-scale structure on a regional basis in the Gulf of Mexico and coastal Atlantic waters off the United States. Individuals sampled non-invasively from four sites, Sarasota, FL (n = 143), the Everglades, FL (n = 36), Ft. Pierce, FL (n = 8), and the southeastern U.S. Atlantic coast (n = 24), were genotyped across eight microsatellite loci. Standard tests...