Popular species processed include cod, hake, haddock, tuna, herring, mackerel, salmon and pollock.
Processing varies regionally in productivity, type of operation, yield and regulation.
[citation needed] Seventy-five percent of fish processed is for human consumption.
[citation needed] Processing can start either on the fishing vessel or at the plants.
Examples of oily fish include salmon, tuna, mackerel, herring and anchovy.
Due to the oil content, gutting and heading is avoided to reduce the risk associated with oily surfaces.