"Pygmy sperm whales are usually seen in small groups of six or fewer individuals, but there are few documented sightings. They tend to stay in deep water, beyond the continental shelf, and not much is known about their behavior. Calves are about 1.2 m long at birth (an adult's total length ranges from 2.7 to 3.4 m); gestation lasts 9 to 11 months; and the calf nurses for about a year. Although strandings are relatively frequent in the southeastern United States, sometimes because the whales have swallowed plastic bags, these animals are sighted so infrequently that they are considered uncommon for conservation purposes. Pygmy sperm whales are believed to feed mostly on cephalopods, and may mistake floating plastic bags for squid."

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Mammal Species of the World