Other names: Aku, Atu, Atun, Bonite, Bonite á ventre rayé, Bonito, Banjo, Cachurreta, Faolua, Ga'oga Gaiado, Lesser Tunny, Listado, Merma, Mushmouth, Nzirru, Palamatu, Stripe Bellied Bonito, Striped Bellied Tunny, Tunna, Victor Fish.
A skipjack tuna hatchling of 3 millimetres will feed on plankton and then small fish, crustaceans and molluscs to grow to 40cm in its first year. Skipjack are prolific tuna - reaching sexual maturity within a year. They breed rapidly, one female tuna creating 80,000 to 2 million eggs per year until they die at about 5 years old (maximum age is 8 - 12 years). Large skipjack tuna can reach around 20 kilos but most are significantly smaller.
The location of schools of skipjack tuna varies widely and is thought to depend on ocean currents and temperatures, with schools mostly found enjoying water temperatures above 25ºC (68º F). Countries between latitude 10ºN and 10ºS are particularly rich in skipjack tuna schools. Skipjack like to travel with floating objects or large marine mammals; and often school according to size so that tuna swimming together have the same speed for travelling and feeding. All the large predators such as sharks and billfish commonly prey on skipjack tuna.
Skipjack tuna can be caught on lines or by net. They are commonly caught by Pacific Island pole-and-line fleets, Japanese pole-and-line fleets, and domestic fleets in Indonesia and Philippines using a variety of methods. Small, local fisheries for skipjack and other tuna (using mainly trolling and traditional methods) occur in many of the Pacific Islands. Some Pacific Islands are looking at reviving pole and line fishing to meet local and niche markets.
By far the most common way for skipjack tuna to be caught is in the large purse seine nets of far-roaming national fleets from Japan, Korea, Taiwan and the USA in the Western and Central Pacific Ocean. Philippines and Indonesia have made up to 20 - 25% of the total skipjack tuna catch in recent years. Stocks of skipjack tuna are considered abundant, making up 70% of the total tuna catch in the Pacific Ocean. During the 1990s, annual catches from this region were about 500,000 - 800,000 tonnes before increasing sharply to approach 1,000,000 tonnes from 2004 to 2006.
High quality sashimi skipjack tuna has deep red coloured flesh that becomes lighter when cooked. It has a stronger taste than other tunas and a short shelf life. It must be consumed 6 days after landing or the red flesh will quickly turn brown and soft. Most skipjack tuna is canned in Thailand, Vietnam and Philippines. However, Pacific Island countries of Samoa, PNG and Solomon Islands also have active canneries. A portion of skipjack is sold fresh and frozen. In Japan, skipjack tuna is known as katsuo, and is commonly smoked and dried to make katsuobushi the central ingredient in making dashi (fish stock).