Once abundant in tropical and subtropical waters worldwide, green sea turtles (Chelonia mydas) suffered devastating population declines during the last few centuries. Intense hunting for their meat, shells, and eggs nearly erased them from many regions. However, the tide began to turn with the introduction of legal protections, turtle excluder devices in fishing nets, and the protection of critical nesting beaches. After decades of dedicated conservation work around the world, green sea turtles have reached an extraordinary milestone. In 2025, the International Union for Conservation of Nature (IUCN) has officially reclassified green sea turtles from “Endangered” to “Least Concern” in its Red List of Threatened Species reflecting the global recovery of the species.

In Greece, ARCHELON has been monitoring and protecting sea turtle populations for over 40 years. While the loggerhead sea turtle (Caretta caretta) nests on many beaches in our country, the green turtle prefers warmer waters. Typically, its breeding areas in the Mediterranean are limited to its easternmost tip, mainly in eastern Turkey, Cyprus and Syria. However, in recent years, some green turtle nests have been recorded in Greece, indicating that the geographical spread of this species’ nesting areas in the Mediterranean is beginning to expand.

ARCHELON researchers and partners have contributed significant scientific knowledge on the changing distribution and behavior of green turtles in the region:

2007: First Green Turtle Nest Recorded in Crete Margaritoulis et al., 2019 ARCHELON recorded the first green sea turtle nest in 2007 on the beach of Rethymno, confirmed by the hatchlings that emerged.

2019: Second Green Turtle Nest Recorded in Crete Margaritoulis et al., 2023 In July 2019, a green turtle was observed laying eggs on Kalamaki beach (Messaras Bay) in southern Crete.

2023: First Green Turtle Nest Recorded in Rhodes Teneketzis et al., 2024 The first green sea turtle nest on the island of Rhodes was recorded during the surveys conducted by ARCHELON with the help of researchers from Rhodes Aquarium - Hydrobiological Station of HCMR and local volunteers.

2024: Two More Green Turtle Nests in Crete Panagopoulou et al., 2025 Researchers from ARCHELON and from the Natural History Museum of Crete documented two additional green turtle nests in Crete (Damnoni beach and Chryssi island) confirming the westward expansion of the species' nesting range, possibly linked to increased sea temperatures due to climate change.

2025: First Green Turtle Nests Recorded in Naxos Lykouropoulou and Orfanos, 2025 In the summer of 2025, the organization “Naxos Wildlife Protection” recorded two green turtle nests on the island. These nests are the northernmost green turtle nests in the Mediterranean, an indication that the green turtle’s breeding range expansion continues not only westwards but also northwards.

The IUCN’s most recent assessment reports a 28% increase in global green turtle numbers since the 1970s, demonstrating the power of coordinated conservation actions. This marks one of the most encouraging success stories in marine conservation: a species once driven to the brink by overexploitation, now showing signs of long-term recovery thanks to international cooperation, protective legislation, and grassroots efforts across the globe.

Still, conservationists emphasize that this is not the end of the story. Continued research, protection and monitoring are essential to prevent backsliding. As new nesting sites emerge across the Aegean, ARCHELON remains at the forefront, ensuring that this hard-won recovery is protected and carried forward into the future.