What Do Sea Turtles Eat?

Sea turtle diets vary significantly by species. Loggerhead turtles eat crustaceans, molluscs including bivalves and hardhead silverfishes, cephalopods, and ray-finned fishes. Leatherback sea turtles specialize in eating jellyfish and gelatinous organisms including violet snails and carinaria that drift in open ocean. Green sea turtles transition from omnivorous hatchlings to primarily herbivorous adults, eating seagrass and algae. Hawksbill turtles eat sponges, jellyfish, and tunicates found on coral reefs. Kemp's ridley sea turtles eat molluscs, crustaceans, and small fish in shallow coastal areas. Flatback turtles feed on sea cucumbers, sponges, and jellyfish. Adult olive ridley turtles are primarily carnivorous, eating fish, molluscs, and crustaceans. The exact food preferences depend on what prey species are available in each turtle's home ocean region. Learn more about these ocean giants at wildlife.

Sea turtle feeding patterns fluctuate with ocean temperatures, water current changes, and prey availability throughout the year. During warm months when ocean productivity peaks, sea turtles find abundant food. Jellyfish populations, which are critical food for leatherback sea turtles, increase during certain seasons and decrease in others. This seasonal abundance and scarcity drives leatherback migration patterns across entire ocean basins. Green sea turtles feeding in shallow seagrass beds have more consistent year-round food availability than oceanic species. Loggerheads hunting molluscsin nearshore waters experience seasonal prey fluctuations. In cooler seasons, turtles may travel to different water temperatures and regions to follow prey migrations. Cephalopods and ray-finned fishes that sea turtles hunt also show seasonal abundance patterns. Young turtles in nearshore nurseries may experience more seasonal food variation than adults in open ocean. Turtle diving behavior and time spent foraging changes seasonally based on food abundance.

Sea turtle diet varies dramatically based on ocean region and available prey species. Sea turtles in Hawaii eat different fish and invertebrate species than those in Florida waters. Texas Gulf Coast sea turtles feed on local bivalves, small fish, and crustaceans found in shallow bays and estuaries. Atlantic sea turtles have access to different jellyfish species, fish, and molluscs than Pacific sea turtles. Cold-water currents bring different prey species and jellyfish populations to different regions. Tropical turtles find abundant sponges and reef invertebrates in coral reef environments. Temperate-zone turtles adapt to cooler water prey including different fish and cephalopod species. The coral reef ecosystems where hawksbill sea turtles live provide unique sponge and tunicata species unavailable elsewhere. Open ocean leatherbacks follow jellyfish blooms that occur in different ocean basins seasonally. Geographic isolation has led sea turtle populations to specialize on locally available food sources.

Sea turtles use different hunting and feeding strategies based on their species and food preferences. Loggerhead turtles use powerful jaws to crush the hard shells of molluscs and crustaceans found on the ocean bottom. Leatherback sea turtles have flexible jaws and throat allowing them to swallow large jellyfish and gelatinous prey whole. Their esophagus has backward-pointing spines that help retain slippery jellyfish and prevent them from escaping. Hawksbill turtles have pointed snouts that help them probe into coral crevices to extract sponges and other reef invertebrates. Green sea turtles use sharp beaks to bite seagrass and scrape algae from rocks in shallow coastal areas. Sea turtles navigate using ocean currents, temperature changes, and chemical cues to locate food-rich areas. Young sea turtles eating jellyfish, invertebrates, and small fish spend much of their time near the ocean surface where sunlight penetrates. Diving ability increases as turtles mature, allowing adults to forage at greater depths for benthos-dwelling prey including cephalopods and ray-finned fishes.

Sea turtle hatchlings eat a completely different diet than the adults they will become. Hatchlings are small enough to eat tiny jellyfish, zooplankton, and small crustaceans drifting in ocean currents. Young sea turtles spend their first years in open ocean nursery areas where they eat gelatinous organisms and small fish. As juveniles grow larger, they gradually transition toward adult diet preferences specific to their species. Loggerhead turtles shift from eating soft-bodied invertebrates to eating hard-shelled molluscs and crustaceans as their jaws strengthen. Green sea turtles transition from omnivorous juvenile diets to herbivorous adult feeding patterns once they reach about one meter in length. This dietary shift corresponds with movement from open ocean nurseries to nearshore seagrass beds. Kemp's ridley turtles eat whatever appropriately-sized prey they encounter, gradually specializing as they mature. The size of available prey determines what young turtles can eat, as their small mouths cannot accommodate large prey. Growth rate depends heavily on nutrition quality and food abundance during these critical juvenile years.

Sea turtles living in human-populated coastal areas encounter both threats and occasional food sources related to human activity. Plastic bags and other floating debris resemble jellyfish to sea turtles and cause injury or death when eaten. Fishing nets and lines entangle sea turtles and prevent them from feeding or surfacing to breathe. Some sea turtles learn to feed on discarded fish remains at fishing ports and around boats. This behavior increases injury risk from propellers and nets. Boat strikes injure and kill foraging sea turtles in shallow coastal waters. Coastal pollution, including pesticides and chemicals, contaminates prey species and accumulates in turtle tissues. Artificial lighting on beaches disorients hatchlings heading to sea. Protecting critical sea turtle feeding habitats and reducing marine pollution helps ensure turtles find safe, clean food. Supporting regulations that restrict fishing in sea turtle feeding areas allows populations to recover. Reducing single-use plastics prevents entanglement and prevents this toxic prey from entering ocean food webs.

Sea turtles occupy overlapping feeding niches with other large marine animals. Seabirds including cormorants, penguins, and albatrosses also eat fish and squid but have different diving depths and range than sea turtles. Marine mammals including dolphins, seals, and manatees eat fish and invertebrates but use different hunting strategies. Large fish species compete with sea turtles for some prey including small fish and cephalopods. Jellyfish predators including ocean sunfish eat some of the same jellyfish species as leatherback turtles. Sea turtles are unique among marine reptiles in their herbivorous and omnivorous feeding strategies. Green sea turtles are among the few large marine animals that transition from omnivory to herbivory as they mature. The specialized feeding behaviors and prey preferences of different sea turtle species allow them to coexist in the same ocean regions without complete dietary overlap. This specialization by species and life stage makes sea turtles an important part of complex ocean food webs. Learn more about sea turtle behavior and sounds in additional resources.