Katsuwonus

Katsuwonus is a genus of pelagic tuna in the family Scombridae. The best-known member is Katsuwonus pelamis, the skipjack tuna, a highly migratory species of major commercial importance. In some classifications, Katsuwonus is treated as monotypic with K. pelamis as the sole valid species; other treatments describe additional species within the genus, but these are not consistently accepted and are often treated as synonyms of K. pelamis.

Katsuwonus pelamis is found in tropical and subtropical oceans worldwide. It inhabits open-water environments from the surface to mid-water and forms large, fast-swimming schools. Juveniles occur in warmer, shelf-edge waters, while adults undertake extensive migrations.

Skipjack are opportunistic predators, feeding on small fishes, crustaceans, and cephalopods. They grow to about a meter in length and can weigh up to several tens of kilograms, with most individuals smaller. Reproduction occurs in warm waters with females capable of multiple spawning events during a season.

Skipjack tuna is among the most widely caught tunas, targeted by purse seines, longlines, and pole-and-line fisheries. Caught fish are primarily processed for canned tuna and other products, contributing substantially to global fish commerce.

Regional stock management is handled by international bodies such as ICCAT (Atlantic), IOTC (Indian Ocean), IATTC (Eastern Pacific), and WCPFC (Western and Central Pacific). The IUCN lists Katsuwonus pelamis as Least Concern, reflecting its broad distribution and high productivity, although regional overfishing and bycatch remain concerns in some areas.