Loggerhead turtles rely on their vision while hunting for jellyfish in the open ocean — not their hearing or sense of smell, new research has found. The new research — from the University of Tokyo — was done by tracking the turtles’ underwater movements with with 3D loggers and National Geographic Crittercams.
The researchers also found that the turtles observed for the study foraged for jellyfish — and similar prey — roughly twice every hour. The researchers think that this means that the turtles may be more reliant upon jellyfish for nutrition than was previously thought.
“Previous studies have shown that turtle diets vary with their age, habitat and other factors, but adult turtles depend on deep-sea hard-shelled animals like mollusks for food. The gelatinous prey studied here are low-energy, easily digestible foods that are unlikely to replace these other prey. However, the authors suggest that opportunistic foraging on such prey may benefit loggerhead turtles during oceanic migrations, when prey at the bottom of the sea is harder to reach.”
The researchers note that the new insight into the diet of the endangered animal may aid in the development of maps detailing where the “areas with higher foraging opportunities along oceanic migratory routes for loggerhead turtles” are.
The new research was just published in the open access journal PLOS ONE.