Ηow important is it to protect adult sea turtles in the Med?
The work of A. Rees, P. Theodorou and D. Margaritoulis of ARCHELON for estimating the clutch frequency of loggerheads nesting in Kyparissia bay, Greece, was recently published. Kyparissia Bay is hosting the largest concentration of loggerheads turtles in the Mediterranean in recent years. This is the first time that clutch frequency (the number of nests made by the same female in a season) has been determined for the sea turtles breeding there.
Satellite tags were used on 21 female loggerheads to monitor their inter-nesting movements in the areas in 2018 and 2019. Thanks to ARCHELON’s multiannual tagging and monitoring efforts, it is known that approximately 366 turtles are expected to nest in south Kyparissia Bay every year. In 2019, the average clutch frequency was found to be 3.8 nests/ turtle and ranged from 3-5 nests.
The important news is that these results were fed into the models used to estimate the breeding population of loggerheads in the Mediterranean region. The new data, although more accurate, does not change predicted long-term trends in nest numbers. It is impressive though that the estimated number of sea turtles breeding in the Mediterranean is shown to be overestimated by 73%. This is due to the fact that previous calculations used the clutch frequency that was calculated for Cyprus in 2002, which is no longer the case. “Now that we know there are fewer sea turtles breeding in the Mediterranean than we thought, more efforts to protect adult turtles must be taken up” said Thomas Arapis, ARCHELON’s Chair of the Board of Directors.
Once more, the monitoring work undertaken systematically in Kyparissia bay by ARCHELON is bearing useful conservation results. “I hope we will be able to use new tags this year as well”, said Alan F. Rees, the main author of the report. “Thanks are due to MAVA Foundation for their support but also to the volunteers who supported ARCHELON projects in Kyparissia”, he added.
Check ARCHELON’s website: publications
ARCHELON meets with the loggerheads while taking up special protection against COVID19
News flash for volunteers in ARCHELON’s sea turtle conservation programs - Update 30/4/2020
RECENT NEWS
- OUR NEWS17/12/2025
ARCHELON’s Research: Expanding the Map of Mediterranean Green Turtles
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.
- OUR NEWS12/12/2025
The Power Behind Sea Turtle Conservation: Our 2025 Field Leaders
With deep gratitude, we honor all the Field Leaders who contributed to the success of the 2025 Field Projects.
- OUR NEWS10/12/2025
Unprecedented appearance of Leatherback Turtle on a Mediterranean beach
A new scientific record brings to light an extremely rare event for the marine life of the Mediterranean: the first confirmed appearance of an adult Leatherback Turtle (Dermochelys coriacea) attempting to nest in the Mediterranean basin.
- OUR NEWS08/12/2025
Applications Now Open for 2026 ARCHELON Field Leaders Posts!
ARCHELON is pleased to announce that applications are now open for the 2026 Field Leader positions across all nesting projects (applications open until January 31st).
- OUR NEWS05/12/2025
Saving Sea Turtles Together – A Tribute to Volunteers
On Volunteer Day, we take a moment to celebrate all those who came from near and far, put on the blue T-shirt, and embraced this important responsibility.
- OUR NEWS01/12/2025
Laganas Bay, Zakynthos: Successful Loggerhead Reproduction, Ongoing Habitat Problems
On the beaches of the Zakynthos National Marine Park, around 2,155 turtle nests successfully hatched thanks to active protection measures, but human pressures on coastal and marine habitats continue.
- OUR NEWS26/11/2025
A Second Chance: Two Loggerhead Sea Turtles Return to the Sea Thanks to Dedicated Rescues
This summer, two adult loggerhead sea turtles, ‘Aktaia’ and ‘Herbert’, arrived at ARCHELON’s Sea Turtle Rescue Centre needing urgent help after sustaining severe head injuries.
- OUR NEWS11/11/2025
Volunteering Projects 2026: Sea Turtles Need You, the Planet Needs Us!
ARCHELON welcomes volunteers from all over the world and of all ages (over 18) and no prior experience is required! If you speak English, are at least 18 years old, and are in good physical condition, you can do this!
- OUR NEWS10/11/2025
Outstanding Recognition for ARCHELON at the Effective Dialogue Conference 2025
On Thursday, November 6, 2025, ARCHELON received an honorary distinction for its substantial contribution to effective dialogue on sustainability, social responsibility, and the environment
- OUR NEWS06/11/2025
6th Year of Online Tours: The sea turtles are traveling across Greece once again!
Students from every corner of the country, as well as from international schools, have the opportunity to learn up close about the lives of the turtles cared for at the Sea Turtle Rescue Centre in Glyfada, Attica, and to discover how rescue efforts impact the marine world.
- OUR NEWS31/10/2025
The lecture turned into reality: A real turtle rescue for the students from Kallithea!
The students spotted a sea turtle floating in the water right after their educational tour of the ARCHELON Rescue Centre and immediately notified the rescuers.
- OUR NEWS24/10/2025
LIFE MareNatura Documentary Premier
From seabird monitoring and genetic sampling, to unique underwater footage of marine mammals, the testimonies of scientists bring to life the hidden stories of the sea.
- OUR NEWS23/10/2025
ARCHELON participates in the "Science Festival 2025 – The Voice of the Ocean"
The French Institute of Greece is organizing a celebration from 10 to 27 November 2025 dedicated to science and the ocean! World premiere of the LIFE MareNatura documentary on November 13th.
- OUR NEWS22/10/2025
Kyparissia Bay: ARCHELON Records 6,100 Nests and Calls on the State to Immediately Implement the National Action Plan for the Loggerhead
In 2025 approximately 6,100 nests were recorded, marking a 74% increase compared to the average of the previous 12 years!
- OUR NEWS10/10/2025
We bid farewell to a devoted environmentalist and friend, Yiannis Roussopoulos.