ARCHELON has just successfully completed the 2025 deployment of satellite transmitters on Loggerhead Sea Turtles (Caretta caretta) in Crete, as part of the ongoing LIFE MareNatura Project. This year’s work in Crete was extra special: the LIFE MareNatura Documentary team joined us in the field!

Satellite Telemetry in Action

Satellite telemetry allows researchers to track turtle movements in real time, offering insights into their migration routes, foraging areas, and marine habitat use. Waterproof transmitters, attached to the turtles’ shells, send location data to ARGOS satellites every time the turtles surface to breathe. These data are then mapped to visualize their journeys. Furthermore, these high-end transmitters log temperature and diving depth data providing further insights into their behavior at sea.

Following the 2024 deployment of 20 transmitters in the Peloponnese and Crete, our 2025 field team has started the second round with 20 more transmitters, focusing again on the same key nesting beaches. These deployments take place during standardized night survey work, targeting nesting females and are performed by highly trained ARCHELON stuff led by ARCHELON’s Research Coordinator, dr Aliki Panagopoulou and Field Projects Coordinator, Michalis Souroulidis.

Tissue Sampling and Habitat Connections

Complementing the telemetry work, ARCHELON is collecting tissue samples from turtles across five coastal regions in Greece between 2024–2025. Stable isotope analyses of these samples (carbon, nitrogen, and sulfur) provide information on the turtles’ diets helping to identify key feeding areas and ecological links between nesting and foraging habitats.

By prioritizing samples from satellite-tagged turtles, researchers aim to connect where turtles nest with where they feed — offering a fuller picture of their life cycle and threats faced across habitats.

Captured on Film: LIFE MareNatura Documentary

This year’s work in Crete was extra special: the LIFE MareNatura Documentary team joined us in the field! Director Roberto Lo Monaco and MEDASSET’s production team, Nadia Andreanidou and Onteta Netzipi, visited Messara Bay in Crete to capture breathtaking footage of the nesting process and ARCHELON’s satellite tagging and monitoring procedures. In fact, Crete was the last stop of the filming as the Documentary team has filmed all over Greece (and Italy) in order to immortalize the actions of all the different partners and highlight the work of LIFE MareNatura. “This Documentary can function as a tool for raising public awareness, but also as a narrative “bridge” that connects science with society,” explains Nadia.

Informing Protection and Policy

By combining satellite tracking, isotope analysis and other research activities during the LIFE MareNatura project, ARCHELON aims to

a) identify important marine areas like internesting areas, foraging/ overwintering grounds and migratory corridors,

b) assess whether current marine Natura 2000 protections are sufficient,

c) recommend new or expanded marine protected areas, and

d) guide policy changes to reduce threats such as fishing and habitat degradation.

“An expansion of the European Natura 2000 Network by the declaration of new marine protected areas will be the first step to ensure other vital parts of the turtle life cycle further to the breeding”, explains Aliki Panagopoulou.

With satellite tagging completed in Crete and efforts moving into the Peloponnese, the 2025 season continues to bring us closer to understanding the complex journeys of sea turtles. Each turtle is given a name and can be tracked live on our website, connecting the public to their stories and the science behind them.

Stay tuned as the live maps of the 2025 turtle journeys will be posted soon!