Caretta caretta (loggerhead turtle)

morphological characteristics

  • Somewhat flatter, heart-shaped carapace
  • 5 ventral scutes, 5 lateral scutes. 11-13 marginal scutes, supracaudal scute is split; nuchal scute is in contact with the first lateral scute on each side
  • Plastron with 3 pairs of inframarginal scutes without pores 
  • Large head with more then 1 pair of prefrontal scutes and 1 interprefrontal scute; jaws have thick rhampotheca (beak shaped structure).
  • 2 claws on each front flipper,  2-3 claws on each hind flipper
  • Size: 70 - 110 cm carapace length
  • Weight: 70 - 150 kg


Caretta caretta prefers subtropic waters. Its main breeding coasts are in Florida, Georgia, Carolina, the Caribbean, Mocambique and South Africa. Europe’s major nesting beaches are in Turkey and Greece. This species feeds on molluscs, echinoderms and crabs. Adult female Caretta caretta turtles nest every 2-4 years and during one nesting season they make 2-4 nests in 2 weeks. Eggs per nest can vary from 23-134. The incubation time ranges from 44 to 64 days.



Caretta caretta feeds on many different species and is therefore a generalist. Specialists include Eretmochelys imbricata (green turtle) which feeds on sponges or Dermochelys coriacae (leatherback turtle) which feeds mainly on jellyfish. This makes loggerhead turtles very adaptable. They feed on algae, seagrass, jellyfish, sponges, crabs, corals and many more.

Seagrasses play an important role in marine ecosystems as refuge areas for juvenile fish and breeding areas for other organisms. Regular grazing (for example by sea turtles) helps keep sea grasses healthy (avoiding dense overgrowth, low oxygen conditions and diseases.

home for epibionts


Barnacles are among the permanent inhabitants on the carapace of sea turtles. Some crabs such as the Columbus crab (Planes minutus) also travel with their host turtle, including Caretta caretta. These crabs feed on animals and algae growing on the carapace and therefore help to reduce the water resistance (drag). Loggerhead turtles have the most diverse epibiont species of all sea turtles. Epibionts have a neutral relationship with their hosts (i.e. are not parasites in the true sense of the word) but are threatened with drying out during the nesting season when the females are on the beach.


nutrient carrier


Caretta caretta turtles travel long distances in the oceans during their lives and carry nutrient matter and energy from one place to another. Especially the females transport nutrients from energy-rich habitats, like seagrass meadows, to nutrient-poor habitats, like beaches through their nests or excrements.

turtles as prey

Sea turtles play an important role as prey for many different predators in the ecosystem, especially the smaller hatchlings. Fully grown adults can only be attacked by the largest predators, such as sharks. Dead embryos or hatchlings on the beach provide important nutrients for dune vegetation and microorganisms.