es have from 10 to 12 large
prominent teeth, curved slightly backwards and inwards on each side of
each jaw. (_Photos from Point Mugu, Calif. by S. Leatherwood._)]

FALSE KILLER WHALE (T)

_Pseudorca crassidens_ (Owen 1846)

Other Common Names

Mongoose (St. Vincent).

Description

False killer whales in the western North Atlantic reach a length of at
least 18 feet (5.5 m). Males are slightly larger than females. Calves
from 5 to 7 feet (1.5 to 2.1 m) may be seen at any time throughout the
year.

The dorsal fin, located just behind the midpoint of the back, is from 7
to 16 inches (17.8 to 40.6 cm) tall, falcate, and variable to sharply
pointed on the tip. The flippers are characterized by a broad hump on
the front margin near the middle, a characteristic which is diagnostic
for the species.

The body of the species is all black except for a blaze of gray on the
belly between the flippers. This blaze varies from barely visible to
light grayish white similar to but generally fainter than that of pilot
whales. The body is long and slender, and the head is narrow and gently
tapered from the area of the blowhole forward.

Natural History Notes

False killer whales are a social form and may occur in herds of up to at
least 100 individuals. They often jump clear of the water and frequently
ride the bow waves of vessels. They are the only "blackfish" which are
known to do so. False killer whales feed primarily on squid and large
fishes and are notorious for their habit of stealing fish from the lines
of fishermen. The large prominent teeth may be visible on a swimming
animal.

May Be Confused With

False killer whales may be confused with killer whales, pilot whales, or
the smaller, poorly known pygmy killer whale (p. 138) and many-toothed
blackfish (p. 142).

The characteristics distinguishing the species from the killer whale are
tabularized on p. 84; its differences from the pilot whales are
summarized on p. 92.

At sea, false killer whales are distinguishable from the other two
species primarily by their larger size and differences in coloration.
False killer whales are up to 18 feet (5.5 m) in length. Pygmy killer
whales and many-toothed blackfish reach only 8-9 feet (2.4-2.7 m) in
length. Pygmy killer whales have an extensive region of white on the
belly which may extend onto the sides and both pygmy killer whales and
many-toothed blackfish have a distinctive white region on the lips,
us