Skipjack tuna important prey species for sharks and large pelagic fishes and is often used as live bait when fishing for Marlin. It has no scales, except on the lateral line and the corselet (a band of large, thick scales forming a circle around the body behind the head). It commonly reaches fork lengths up to and a weight of . Its maximum fork length is and maximum weight is . Ageing skipjack tuna is difficult, and the estimates of its potential lifespan range between 8 and 12 years. Skipjack tuna is a batch spawner. Spawning occurs year-round in equatorial waters, but
USS Skipjack (SS-184) upward angle developed almost immediately, forcing the submarine to surface. By the time control of the boat had been regained, the water in the torpedo room was only a few inches from the top of the water tight door, but fortunately there were no casualties, and "Skipjack" resumed the attack. The submarine then torpedoed and sank the converted seaplane tender "Okitsu Maru" (). She returned to Pearl Harbor on 7 March. Following repairs, "Skipjack" participated in performance tests on new torpedoes in cold water off the Pribilof Islands until 17 April and then headed for the Mare Island Navy Yard