Why cod can be called quaternary fourth consumer?

Cod can be classified as a quaternary consumer because it occupies a high trophic level in marine food webs. As a carnivorous fish, it preys on smaller fish and invertebrates, which are themselves secondary and tertiary consumers. This position in the food chain means that cod is at the top of the aquatic ecosystem, feeding on organisms that have already consumed primary producers. Consequently, it plays a crucial role in regulating the populations of its prey species.