Are we even close? Five years marine litter ingestion monitoring in loggerhead turtles along Italian coast reveals how far we are from the Good Environmental Status

• Published in: Marine pollution bulletin 2024-08, Vol.205, p.116647, Article 116647
• Main Authors: Matiddi, Marco, Valente, Tommaso, Camedda, Andrea, Centelleghe, Cinzia, Cocumelli, Cristiano, Dara, Salvatore, de Lucia, Giuseppe Andrea, Di Renzo, Ludovica, Ferri, Nicola, Gioacchini, Giorgia, Hochscheid, Sandra, Lucifora, Giuseppe, Maffucci, Fulvio, Monteverde, Vincenzo, Pelamatti, Tania, Petrella, Antonio, Pietroluongo, Guido, Roncari, Chiara, Terracciano, Giuliana, Silvestri, Cecilia
• Format: Article
• Language: English
• Subjects: Animals; Caretta caretta; Environmental Monitoring - methods; GES; Italy; Marine Strategy Framework Directive; Mediterranean Sea; Plastic ingestion; Plastics; Turtles - physiology; Water Pollutants, Chemical - analysis
• ISSN: 0025-326X; 1879-3363; 1879-3363
• DOI: 10.1016/j.marpolbul.2024.116647

The loggerhead sea turtle Caretta caretta has been chosen as bioindicator to monitor the amount of litter ingested by marine animals within the European Marine Strategy Framework Directive and the Barcelona Regional Sea Convention. European Member States and Contracting Parties are committed to achieve the Good Environmental Status (GES), which is reached when the quantity of ingested litter does not adversely affect the health of the species concerned. Although the monitoring strategy has been outlined for more than a decade, to date no threshold values have been adopted to verify GES achievement. After five years of extensive monitoring along the Italian coasts, this study evaluates the suitability of five different GES scenarios and proposes a new threshold value (i.e., “there should be less than 33% of sea turtles having more than 0.05 g of ingested plastic in the GI”) for its implementation in the European seas and the Mediterranean basin. •C. caretta is a good bioindicator of marine litter ingestion at subregional scale.•Two GES scenarios are suitable to monitor the health of the species concerned.•Marine litter ingestion rates seem to be affected by food availability.•C. caretta cannot be considered as a marine litter passive sampler for GES.•No lethal impact has been observed in individuals with ≤0.05 g of ingested litter.