Habitat Utilization and Vertical Movements of the Pelagic Stingray Pteroplatytrygon violacea (Bonaparte, 1832) in the Western North Atlantic Ocean Using Short-Duration Pop-Up Archival Satellite Tags

The pelagic stingray Pteroplatytrygon violacea (Bonaparte, 1832) 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 pelagic longline fishing gear could be used to develop fisheries bycatch mitigation techniques. Four pop-up satellite archival tags (PSATs) with 13-day deployment durations were attached to pelagic stingrays in 2010 and 2011 in both the South Atlantic Bight (n=2) and the northern Gulf of Mexico (n=2). Analysis of the minimum straight-line distances from the first transmission locations showed that pelagic stingrays moved between 151-258 kilometers (km) from where each stingray was released (11.6-19.8 km/day). PSAT data indicate significant diel difference in behavior, with all four animals utilizing deeper depth during daylight periods. All four stingrays appeared to follow a temperature regime above all other variables. 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. Applying the known habitat utilization and behavior of less economically important species will help fisheries managers better understand both overall interactions with more economically valuable target species and the overall pelagic ecosystem.