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
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When we analyzed the turtles’ codes, we realized that this was a turtle that had been tagged for the first time in the area 32 years ago! Specifically, turtle P4849 was tagged on July 7, 1993 and today is the turtle with the longest documented reproductive lifespan in Kyparissia Bay!
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The presentation of our Accounts for 2025 was held with great success on Saturday, February 14th in Glyfada, honoring the people who are on the front lines for the protection of the Mediterranean.


