Social media posts help shed light on the impacts of “turtle spotting” in Laganas bay, Zakynthos
The reduction of human disturbances from nesting beaches during 2020 has eased the egg-laying of sea turtles, but who can forget the race for turtles performed by ‘turtle spotting’ boats during the last years in Laganas bay? Tourist and sea turtle interactions at sea need to be better regulated in the National Marine Park.
The island of Zakynthos has become a major international tourist destination, receiving hundreds of thousands of holiday makers per year. Every summer, a large number of tourists typically observe sea turtles either from a boat, usually by organized boat tours or by snorkeling in the blue waters of Laganas bay.
Two ARCHELON members - Kostas Papafitsoros and Aliki Panagopoulou- along with Gail Schofield are the authors of an innovative scientific study shedding light in tourist and sea turtle interactions in Laganas bay, which was published in the journal Animal Conservation as open access article last month.
The study examined more than 3500 social media photos and videos of loggerhead sea turtles taken in Laganas bay during 2018 and 2019. The team used photo-identification techniques to quantify how much and how often each individual loggerhead was photographed by people on boats and by snorkelers. It was thus possible to obtain entries of 139 unique turtles in a total of 1684 viewings in 2018 and 122 unique turtles in 2105 viewings in 2019 (boats and underwater viewings combined).
One might have expected that turtles uniquely identified would have a similar representation in the viewings, but this was not the case. It was shown that only a few of them featured in the vast majority of social media posts both during 2018 and 2019. In fact, 54 “resident” turtles (defined as males encountered after June, females encountered after early August and immature turtles frequenting the area at any given time) were found to represent 81.9% and 87.9% of all entries in 2018 and 2019 respectively. This finding suggests that boat tour operators may be specifically targeting the areas of Laganas bay that these “resident” turtles are frequenting.
The study also showed evidence of carapace damage by boats on 9 out of the 54 “resident” turtles viewed in 2018 and 2019. One of them, the male loggerhead which was found to be the most photographed turtle by people on boats in both years, was the one that ended up fatally injured in 26 July 2019 by boat propeller, possibly during “turtle spotting” activities.
Amongst other interesting findings, it was shown that snorkelers photographed different turtles than those photographed by people on the boats. This suggests that snorkelers tend to be more uniformly distributed around the Bay and their encounters with turtles are more "random" than those of the “turtle spotting’ boats.
The authors point to the need of further studies but also to a stricter enforcement of the 6 knot speed limit that currently exists in the bay. They also suggest that the use of propeller guards should be made compulsory to all the boats used for turtle spotting in Laganas Bay.
Concerns about the impacts of the ever increasing “turtle spotting” pressure in Laganas Bay have been raised consistently by ARCHELON and MEDASSET during the last years. Clearly there is more to be said and done to improve sea turtle conservation in this area.
Read or download the publication in our page here.
Check out the on line publication and supporting material.