Notes On the Food of Sea Turtles: Eretmochelys Imbrica Ta (Linnaeus) and Dermochelys Coriacea (Linnaeus)

Abstract

The present paper deals with the results of a study of the contents of the entire alimentary canal of a small hawksbill turtle (Eretmochelys imbricata (L.)), captured at Selvagem Pequena (subtropical eastern Atlantic), and of a sample of stomach contents of a leathery turtle (Dermochelys coriacea (L.)), taken near Malta (Mediterranean). Apart from some man-made litter and vegetable material, the stomach and the intestines of the hawksbill appeared to contain mainly animal matter: remains of sponges, sea anemones (Anemonia sulcata (Pennant)) and other coelenterates, oceanic squid, gastropods, etc., of which Anemonia sulcata constituted the main bulk. So far, sea anemones were never reported to be preyed upon by sea turtles. Hawksbill turtles are generally considered omnivorous, as they appear to devour both animal and vegetable matter. Their ability, however, to digest (to a significant degree) the vegetable components of their diet, is here disputed. The sample of stomach contents of the leathery turtle demonstrated that it had eaten at least two species of Siphonophora and one species of Scyphozoa. The presence of remains (nematocysts) of the mesopelagic siphonophore Apolemia uvaria Lesueur might imply that the leathery turtle reaches considerable depths in search for food.