For the first time, a mackerel tuna—also known as kawakawa and long considered nearly impossible to breed—has reproduced naturally in captive conditions at a research center in the Philippines. The tuna (Euthynnus affinis), known in the Philippines as “tulingan,” spawned at the Southeast Asian Fisheries Development Center Aquaculture Department (SEAFDEC/AQD) in Tigbauan, Iloilo, without the use of hormone injections. The first spawning event under fully captive conditions was recorded in July 2025, with repeated spawning observed through September.

SEAFDEC achieves world's first natural captive spawning of mackerel tuna. (2026, January 17-18). DailyGuardian, pp. 7, 11.