Cephalopod beaks from the stomachs of Indo-Pacific finless porpoises (Neophocaena phocaenoides) and a green turtle (Chelonia mydas) stranded in the Gulf of Thailand

During January 2020 to February 2022, 115 cephalopod beaks (62 upper beaks and 53 lower beaks) were collected from the stomachs of seven Indo-Pacific finless porpoises (Neophocaena phocaenoides) and one green turtle (Chelonia mydas) that had stranded along the Gulf of Thailand in Phetchaburi, Prachuap Khiri Khan, and Samut Sakhon provinces, Thailand. The beaks came from four prey species: needle cuttlefish (Sepia aculeata), sandbird octopus (Amphioctopus aegina), bigfin reef squid (Sepioteuthis lessoniana), and pharaoh cuttlefish (Sepia pharaonis). The Indo-Pacific finless porpoises contained 114 beaks (108 from Sepia aculeata, 4 from A. aegina, and 2 from Sepioteuthis lessoniana), and the green turtle contained a single upper beak from Sepia pharaonis. Prey mantle lengths were estimated from beak dimensions and ranged from 3.95 to 6.94 cm (5.21 +/- 0.76) in Sepia aculeata and from 5.15 to 6.73 cm (5.89 +/- 0.80) in A. aegina. Mantle lengths of Sepioteuthis lessoniana and Sepia pharaonis were not estimated due to the limited data available for these species in Thai waters.