Whaling reduced the populations of Sei whales from an estimated 50,000 in 1963 to a low of 20,000 in 1974. At present the populations are thought to be recovering.

Brief Description:

• Typical full-grown length: up to 19 meters (62 feet)

• Color: dark steel gray on back, often with grayish-white scars that make body appear mottled; white on front of belly; undersides of flippers and flukes are dark

• Dorsal (back): fin is up to 2/3 meters high and strongly hooked ("falcate"); it's located more than one-third forward from end of fluke ("tail"), and it usually forms an angle of more than 40 degrees with its back

• Tail movement: not raised on dives

• Other distinguishing characteristics: baleen ("teethlike") are black with fine white to light gray bristles

• Habitat: extensively distributed; not very common in the coldest waters in either hemisphere and may have a greater tendency than fin whales to enter tropical waters; found more northernly in the summer.