Opportunistic predator that forages mainly at dawn and dusk (Refs. 1371, 46189). Larvae feed mainly on zooplankton while juveniles prey predominantly on benthic crustaceans; adults feed mainly on zoobenthos and fish (Refs. 5743, 9604, 26813) including juvenile cod. Fish prey becomes more common in the diet with increasing body size (Refs. 1371, 89387). Adults may cover large distances during the feeding period (Ref. 89387). Young cod are also preyed upon by different fish species and octopus. Adult cod are prey items of top predators like sharks, rays, whales, dolphins, seals, and sea birds (Refs. 9023, 9581, 26954, 43651, 45735).In the Baltic it grows up to 5 kg weight in 7-8 years; in the North Sea it reaches 8 kg in the same time span . Natural mortality for adults of both stocks is assumed to be around M=0.2, resulting in a mean adult life expectancy and mean duration of the reproductive phase of 5 years (Ref. 88171).Parasites of the species include protozoans (trypanosome), myxosporidians, monogeneid, trematodes, cestodes, nematodes, acanthocephalan, hirudinid and copepods (Ref. 5951).