Sporadic nesting grounds of loggerhead turtle on the Aegean coasts of Türkiye

Oguz Turkozan, Bahattin Sürücü

ORCID IDs: O.T. 0000-0001-6889-7908; B.S. 0009-0004-9318-4781

Department of Biology, Faculty of Science, Aydın Adnan Menderes University, Aydın, TÜRKİYE
EKODOSD, Şafak Sok. No. 7, 09400, Kuşadası, Aydın, TÜRKİYE

Abstract

Loggerhead sea turtles (Caretta caretta) are expanding their nesting range in the Mediterranean, likely in response to rising sea surface temperatures. While major nesting grounds are well-documented in southern Türkiye, sporadic nesting in the Central Aegean remains poorly understood. We analysed 14 years (2012–2025) of nesting data from Kuşadası and the surrounding region, evaluating temporal trends, spatial hotspots, and reproductive parameters, including clutch size, hatching success, and incubation duration. Nesting activity exhibited a significant exponential increase (y=0.070⋅e ^0.402x), transitioning from an average of 1.3 nests per year (2012–2022) to a record high of 13 nests in 2025. Spatial analysis identified Parlamenterler Sitesi (Didim) and Ayyıldız Cafe (Kuşadası) as emerging hotspots. While clutch size (70.7±15.6) did not correlate with hatching success (p>0.05), seasonal declining trend in success was observed, with June nests (75.2%) outperforming August (48.6%) nests. Mean incubation duration (53.2±4.5 days) confirms the thermal suitability of these beaches. The Kuşadası region is transitioning from a sporadic to a regular minor nesting ground. Conservation efforts should prioritize the “early-season success window” and the protection of newly identified hotspots to support this range expansion.

Keywords: Caretta caretta, nest, hatchlings, Kuşadası, Türkiye

Pages: 79-91

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