Habitat Utilization and Short-Duration Movements of the Pelagic Stingray Pteroplatytrygon violacea in the Western North Atlantic and Northern Gulf of Mexico

The pelagic stingray Pteroplatytrygon violacea is the only true pelagic dasyatid stingray, and the species is commonly encountered as bycatch in the pelagic longline fishery targeting swordfish and tunas. However, very little is known about its habitat utilization and whether depth or temperature differences between the pelagic stingray and the pelagic longline gear type could be used to develop fisheries bycatch mitigation techniques. Four pop-up satellite archival tags (PSATs) with 13-day deployment durations were deployed on pelagic stingrays in 2010 and 2011 in both the South Atlantic Bight (n=2) and the northern Gulf of Mexico (n=2). Data from these tags indicate clear diel difference in behavior, with all four animals displaying deeper depth utilizations during daylight periods. All four stingrays appear to be following a temperature regime above all other variables. Differences in depth were examined to determine the speed and the range of the vertical movement between sequential 90 second point data. All four animals also displayed frequent short-duration (ca. 5-minute lengths) movements of more than 50 m from the “baseline” depth of the diel period and a thermal range of approximately 8°C over 24-hour periods