It shares with the blue whale the distinction of having the deepest voice on earth. The finback often feeds by coursing through the water on its side, straining out krill and small fish through its baleen plates. This species also makes some of the deepest dives of the baleen whales, and has remained submerged for as long as 50 minutes on a single breath.
Finbacks tend to be restless and easily spooked.
They avoid noisy boats, but will swim up beside a stopped vessel. In autumn, these whales migrate several thousand miles to equatorial waters. During winter, they fast almost completely, living off their fat reserves. Mating occurs throughout the winter and young are born a year later between December and April. A calf, measuring 20 feet at birth, will nurse for about 7 months and reach sexual maturity at the age of 5-6 years.