Satellite Marking project

Project developed and executed by the Azul Marino Foundation in collaboration with the Oceanogràfic Foundation
Phase 4:

Satellite marking project of four postneonates of Caretta Turtle

The Azul Marino Foundation has financed the purchase of satellite transmitters for the subsequent monitoring of 4 specimens from a nest located on the Serradal beach in Castellón (07/13/2019). These specimens were released after 15 months from the ARCA del Mar of the Oceanogràfic Foundation (neonates 4 and 9) and in the Seville Aquarium (neonates 12 and 27).

Newly hatched sea turtles (Caretta caretta) are very vulnerable to predators, such as crabs, birds, and fish, due to their small size. It is estimated that mortality in the first days reaches 90% and that only 1 in 1000 specimens will reach adulthood. Captive breeding within head- start projects have a better chance of survival due to larger sizes reducing predation.

To evaluate the survival of the animals once released and to know their movements, we currently have an indispensable tool: satellite transmitters.

They are small devices that are fixed with putty and silicone to the shell. After a few months of growth the devices come off without causing harm to the animal. For this project, solar satellites brands of the Desert Star model Seatag-TT 21 g have been used.

When the turtle is on the surface of the water they emit a signal that can be detected by Argos satellite system. Precision of location will Depend on the number and strength of the signals received from a device.

With the marking of these specimens the following objectives are pursued:

  • monitoring of survival of the animals and their adaptation to the environment, helping to evaluate the degree of success of the head-start project;
  • generate basic information on the species during this open ocean life phase that before was relatively unknown, enabling the observation and analyzation of the routes, dispersal zones and habitat use of turtles.


Since the turtles were released (10/15/2020), we are constantly receiving data from all transmitters. After the first weeks, which are considered critical in the reintroduction process, all data received indicates that they have adapted well to life at sea.

The monitoring will continue while the devices are in operation and we hope to generate information on their routes and dispersal areas, thereby supporting the work being carried out by other entities within the Sea Turtle Conservation Strategy of the Valencian Community.

By contributing these emitters we are actively contributing to the conservation of the species, classified as “Vulnerable” in the Spanish Catalog of Threatened Species and included in


Annexes II (Species for which it is necessary to designate special conservation areas) and IV (Species that require strict protection) of the “Habitats Directive”.

This project is part of the collaboration agreement signed between the Azul Marino Foundation and the Oceanogràfic Foundation.

marcas satelites
Play Video

Greater knowledge,
greater protection

The satellite tagging of turtles allows us to expand the knowledge and information we have and apply it to the protection of a species included as “Vulnerable” in the Spanish Catalog of Threatened Species

Flecha arriba
The Oceanogràfic Foundation released 20 loggerhead turtles (Caretta caretta) this afternoon on El Serradal beach in...
Flecha arriba
Two of the three chelonians were accidentally captured in Benicarló and Burriana and the other in...
Flecha arriba
After thousands of kilometers and several months on the coasts of Greece, the turtle released in...