ecology of sea turtles

140 million years ago, 4 different taxonomic families of sea turtles roamed the oceans. Today, the 7 remaining species are restricted to 2 families, whereby 1 family contains only a single species:

Family Cheloniidae

Loggerhead Turtle (Caretta caretta)*
Green Turtle (Chelonia mydas)*

Flatback Turtle (Natator depressus)
Hawksbill Turtle (Eretmochelys imbricata)
Kemp’s Ridley (Lepidochelys kempii)
Olive Ridley (Lepidochelys olivacea)

Family Dermochelyidae

Leatherback Turtle (Dermochelys coriacea)


(* : During field work these species can be encountered, and they are therefore described in more detail than others)


Most sea turtles inhabit tropical or subtropical seas. In addition to providing a home for the loggerhead and green turtles, the Mediterranean is known to contain a few hawksbill, leatherback and Kemp’s ridley turtles. Only the loggerhead and green turtles actually nest here.

breeding season

After mating, the female loggerhead turtle emerges onto the beach at night to lay approx. 100 eggs. She then immediately returns to the sea. After about 2 months, the young turtles, so-called hatchlings, emerge from the nests and make their way to the water. This normally takes place at night as well, which provides protection against the heat of the sun and predators (crabs, dogs, birds, fishes). According to an often-cited estimate, only 1 of 1000 hatchlings will reach sexual maturity and return to the nesting beach. As the turtles typically return to the same beach where they were born, it is particularly important to protect these beaches. Even if they rarely actually see a turtle, tourists can play an important role on nesting beaches by heeding the following rules and tips:

international conservation efforts

Turtle studies conducted worldwide generally show the same disturbing trend: the number of individuals in the respective populations is sinking. All species are therefore classified as endangered or threatened (IUCN) and therefore protected by a wide range of conventions and agreements.

  • Convention on the International Trade in Endangered Species (CITES), which regulates trade with sea turtles or sea turtle products between signatory states. All sea turtles are listed in Appendix 1 (highest protection status).
  • Bern Convention (Convention on the Conservation of European Wildlife and Natural Habitats.
  • Bonn Convention (Convention on the Conservation of Migratory Species of Wild Animals).
  • SPA protocols (Special Protected Areas) designed to protect the marine environment and to avoid environmental pollution.


Our partner in the sea turtle project, Turkey, is a member of all the above conventions.


There is a broad range of reasons for the decline of sea turtles. These include collisions with boats, beach pollution and destruction, so-called by-catch in marine fisheries, and increased egg predators on the beach. Sea turtle projects strive to protect turtles both in the sea and on their nesting beaches. Protective measures on the beaches, for example, can include setting up protective cages around the nests, constructing hatcheries (transferal of eggs to more suitable locations), collecting hatchlings and releasing them in better suited, darker sections of the beach, and recognizing and documenting threats on the beach. The latter include fires and lights at night, automobile and motorcycle traffic, sand removal for the construction industry, the erection of buildings or other structures on the beach, the planting of trees, illegal garbage dumps ...

Most tourists are unaware that they are spending their vacation on sea turtle nesting beaches. One reason for this is that they rarely actually see a turtle because the adult animals lay their nests at night and the young hatchlings also emerge at night. This makes public relations efforts in the broadest sense an important element of our project. Therefore, there is broad cooperation with the local media, and our Turkish-Austrian turtle team gives numerous interviews to local TV teams and newspaper reporters. At regular intervals, an information desk is set up on the promenade and brochures are distributed to passersby. This is supplemented by the sale of turtle-related souvenirs such as T-shirts, postcards, and coloring books and colored pencils. An effort is made every year to hold short talks in selected hotels, although this is not always successful.