The Impact of Lunar Phases and Illegal Light Use on Purse Seine Fishery in Türkiye’s Mediterranean Waters

Year 2025, Volume: 14 Issue: 1, 1 - 9, 31.03.2025

Sevil Demirci , Emrah Şimşek

https://doi.org/10.33714/masteb.1598558

Abstract

This study examines the purse seine fishing activities along the Mediterranean coast of Türkiye between 2013 and 2020, with a particular focus on the apparent fishing hours in regions such as Iskenderun, Mersin, Anamur, Antalya, and Fethiye. Data obtained through the Global Fishing Watch platform have been used to assess the impact of lunar phases and illegal light usage on fishing practices. Analyses indicate intensified fishing activities in regions like Fethiye, where light usage is permitted, and Iskenderun, where it is prohibited. This intensity is especially evident during the dark lunar phases, highlighting increased fishing efforts associated with illegal light usage. The research observes how fishing activities differ in regions with varying legal regulations, such as Iskenderun and Fethiye. Despite the prohibition, an increase in fishing activities due to illegal light usage has been observed in Iskenderun, raising questions about the effectiveness and enforceability of current bans. In Fethiye, where light usage is allowed, there has been a significant increase in fishing hours. Findings and analyses reveal the adverse effects of illegal light usage on sustainable fishing practices and the health of marine ecosystems. The results offer significant insights for developing policies and management strategies to ensure the ecological and economic sustainability of fishing activities along Türkiye’s Mediterranean coast.

Keywords

Lunar phase, Purse Seine, Illegal Fishing, Eastern Mediterranean

Ethical Statement

For this type of study, formal consent is not required.

Supporting Institution

This study was carried out without financial support from any institution.

Thanks

The authors would like to thank the Turkish State Meteorological Service and Global Fishing Watch platform for data collecting and making them available.

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