VII. Diet and Eating Habits.
A. Food preferences and resources.
Diet varies with species. Sea turtles may be carnivorous (meat eating), herbivorous (plant eating), or omnivorous (eating both meat and plants). The jaw structure of many species indicates their diet.
1. Green and black sea turtles have finely serrated jaws adapted for a vegetarian diet of sea grasses and algae. In adulthood, they are the only herbivorous sea turtles, but in an aquarium environment all sea turtle species can be maintained on a carnivorous diet.
2. Loggerheads' and ridleys' jaws are adapted for crushing and grinding. Their diet consists primarily of crabs, mollusks, shrimps, jellyfish, and vegetation.
3. A hawksbill has a narrow head with jaws meeting at an acute angle, adapted for getting food from crevices in coral reefs. They eat sponges, tunicates, shrimps, and squids.
4. Leatherbacks have delicate scissorlike jaws that would be damaged by anything other than their normal diet of jellyfish, tunicates, and other soft-bodied animals. The mouth cavity and throat are lined with papillae (spinelike projections) pointed backward to help them swallow soft foods.
5. Researchers continue to study the feeding habits of flatbacks. There is evidence that they are opportunistic feeders that eat seaweeds, cuttlefish, and sea cucumbers.
B. Eating habits.
Some species change eating habits as they age. For instance, green sea turtles are mainly carnivorous from hatchling until juvenile size; they then progressively shift to an herbivorous diet.
A loggerhead's jaws are adapted for crushing and grinding (left). A leatherback's delicate jaws would be damaged by anything other than soft-bodied animals (right).
