Melon-headed Whale
Order Cetacea : Family Delphinidae : Peponocephala electra Gray

Description. Melon-headed whales are about the same size as pygmy killer whales (Feresa attenuata), with adult males up to 2.7 m and adult females up to 2.6 m in length. Maximum weight is about 225 kg. The profile of the melon-headed whale is not unlike that of the pygmy killer whale; however, while the pygmy killer whale has a totally rounded, bulbous head, that of the melon-headed whale is rounded in profile and on the top, flat below, and seen from bottom or top, forms a distinct triangle between the eyes and the tip of the snout. The dorsal fin is distinct and falcate, and located at the middle of the back. The flippers are long and, unlike those of the pygmy killer whale, pointed at the tips. Each upper jaw has 20-25 sharp-pointed teeth, while there are 22-24 in each lower jaw. This is about twice the number found in the pygmy killer whale and the false killer whale (Pseudorca crassidens), and is a firm identification mark for even decomposed animals.

Coloration is black except on the belly and around the mouth, with the white lips resembling those of pygmy killer whales. Although the belly may be very white, it is usually a light gray and not as distinct as the white belly patch of the pygmy killer whale.

Distribution in Texas. Worldwide in tropical and subtropical waters but most numerous in the Philippine sea. They appear to favor warm, pelagic waters and rarely stray over the continental shelf. Known in Texas on the basis of one animal that stranded alive on Matagorda Peninsula in June, 1990. Previously, the nearest record of occurrence was from the island of St. Vincents in the Caribbean.

Habits. Melon-headed whales travel in groups of 100-1,000, although even larger groups have been reported. In the tropical Atlantic, Pacific, and Indian Ocean they have been reported traveling with Fraser’s dolphin (Lagenodelphis hosei) and with spinner and spotted dolphins (Stenella spp.).

Little is known about their reproductive habits. Calving appears to peak in early spring in the low latitudes of both hemispheres. The length of gestation is not known, but is probably about 12 months. Migration is unknown, and strandings occur year round in tropical and subtropical waters. Melon-headed whales feed mainly on squid and fish.

Illustration credit: Pieter A. Folkens.