The greatest threat to the fin whale in the late 20th century is marine pollution.
Hunting of fin whales depleted the population, although stopped in 1975 some continued in the North Atlantic and there is little evidence of recovery.
An estimated 50,000 to 100,000 fin whales inhabit the North Atlantic, Mediterranean, and Southern Hemisphere. Pre exploitation levels in the Southern hemisphere alone are thought to have been between 300,000 and 1,650,000.