Trophic relationships revealed by dart tags found in the stomachs of large pelagic fishes in the Atlantic Ocean

• Published in: Fisheries research Vol. 248; p. 106224
• Main Authors: Silva, Guelson Batista, Ailloud, Lisa Elma, Amandé, Justin Monin, Muniz, Rafael Ferreira, Hazin, Fabio Hissa Vieira, Beare, Doug
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2022
• Subjects: Acanthocybium solandri; Atlantic Ocean; Brazil; Cannibalism; Cote d'Ivoire; Dart tags; Euthynnus; Katsuwonus pelamis; Makaira nigricans; pelagic fish; Predation; Sao Tome and Principe; sharks; stomach; Tag-recapture; Thunnus albacares; Thunnus obesus; Trophic interaction; Brazil; Sao Tome and Principe; Atlantic Ocean; Cote d'Ivoire; Trophic interaction; Tag-recapture; Dart tags; Predation; Cannibalism
• ISSN: 0165-7836; 1872-6763
• DOI: 10.1016/j.fishres.2022.106224

Plastic dart tags are the main type of tag used in all major fish tagging projects but their potential for studying trophic relationships has never been addressed. The occurrence of dart tags in the stomach contents of large pelagic fishes and direct observations onboard tagging vessels reveal novel information on predation and cannibalism by tropical tunas in the Atlantic Ocean. The observations were all made during the Atlantic Ocean Tropical Tuna Tagging Programme (AOTTP), which targeted bigeye tuna (Thunnus obesus), yellowfin tuna (Thunnus albacares), skipjack tuna (Katsuwomis pelamis), wahoo (Acanthocybium solandri), and little tunny (Euthynnus alletteratus). During the programme (so far) 5 conventionally tagged fish have been reported in stomach contents from captures made in Brazil, São Tome and Principe, and Ivory Coast: including one yellowfin tuna and two skipjack tunas in a yellowfin tuna, one yellowfin tuna in a blue marlin (Makaira nigricans), and one yellowfin tuna in a non-identified shark. We use these observations to illustrate the potential role that dart tags could play in helping describe trophic interactions among marine pelagic fish species. •First report of dart tags in the stomach content of large pelagic fishes.•Case of cannibalism by yellowfin tuna.•Potential use of dart tags to study trophic relationships.