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 (SSN-585) reduced her speed noticeably. During her shakedown cruise in August 1959, she became the first nuclear ship to pass through the Straits of Gibraltar and operate in the Mediterranean. Following post-shakedown availability at Groton, Connecticut, the nuclear submarine conducted type training and participated in an advanced Atlantic submarine exercise from May through July 1960, which earned the submarine a Navy Unit Commendation, and also a Battle Efficiency "E" award, an award it would receive three more times. In late 1960, "Skipjack" entered the mouth of a long ship channel leading from the Arctic Ocean to Murmansk in the Soviet Union.