Do loggerhead sea turtle (Caretta caretta) gut contents reflect the types, colors and sources of plastic pollution in the Southwest Indian Ocean?

We analyzed plastic debris ingested by loggerheads from bycatch between 2007 and 2021 in the Southwest Indian Ocean (SWIO). We also analyzed plastic debris accumulated on beaches of the east coast of Madagascar as a proxy for ocean plastics to compare the characteristics of beached plastics and plastic ingested by turtles. We conducted a "brand audit" of the plastics to determine their country of origin. An oceanic circulation model was used to identify the most likely sources of plastics in the SWIO. In total, 202 of the 266 loggerheads analyzed had ingested plastics. Plastics categorized as "hard" and "white" were equally dominant in loggerheads and on beaches, suggesting no diet selectivity. Both the brand audit and circulation modeling demonstrated that Southeast Asia is the main source of plastic pollution in the region. This study demonstrates that loggerheads can be used as bioindicators of plastic pollution in the SWIO.

• Publication year

  2023

• Venue

  Marine Pollution Bulletin

• Publication date

  2023-07-31

• Fields of study

  Medicine, Environmental Science

• Identifiers
  DOI 10.1016/j.marpolbul.2023.115343PMID 37531795
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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