Spatial, temporal, and dietary overlap of leatherback sea turtles (Dermochelys coriacea) and ocean sunfishes (family Molidae)

Investigation of the spatio-temporal movements of leatherback sea turtles (Dermochelys coriacea) and ocean sunfishes (family Molidae), as well as analyses of their prey, support the hypothesis that they may occupy similar ecological niches. This study examined the spatial and temporal occurrences of sunfishes (Mola mola and Masturus lanceolatus) and leatherbacks in the western Atlantic Ocean and assessed dietary overlap. Analyses of leatherback and sunfish distributions, estimated from aerial surveys, showed greater spatial and temporal overlap along the Northeast coast of North America than in the Gulf of Mexico. Both species co-occur more often during warmer months. Pelagic longline fisheries bycatch data and aerial survey data revealed slightly different trends in spatio-temporal distributions. Nematocysts found within gastrointestinal tract contents of stranded animals indicate that they may feed on similar prey, including cnidarians in the classes Scyphozoa, Hydrozoa, and Cubozoa.