Alaska pollock is the most abundant species in the cod family. Its body is oblong, spotted or silvery in color, and it has large eyes. Alaska pollock inhabits cold waters (2..9° C). It usually lives at depths of 200-300 m, but may descend to 500-700 m when migrating. During spawning, it enters shallow, 50-100 m deep waters. Its lifespan is 15-18 years. Adult pollocks can weigh up to 5 kg and grow to 1 m, but most fish in schools are 40-45 cm long and weigh up to 1.5 kg. It mainly feeds on plankton.