(Australophocaena dioptrica)

Morphology

The Spectacled Porpoise is the largest member of the family Phocoenidae. The length of this species ranges from 1.5 to 2.0 meters, with a maximum length of 2.2 meters reported. This porpoises ranges in weight from 60 to 84 kilograms. The Spectacled Porpoise body is robust, while the head is small and rounded. There is little forehead present, and the beack is lacking entirely.

Color

The dorsal portion of this porpoise is blue-black in color, while the underside is white. The lips are black, and a dark stripe extends from the jawline to the flippers. Similarly, a white stripe runs along the dorsal side of the tail stock. The flippers are white but possess black lining along the borders. The top portion of the fluke exhibits the blue-black coloring of the dorsal side of the animal, while the underside of the flue is white, similar to the belly. One of the most striking features of this species is the coloration around the eyes. Spectacled Porpoise eyes are surrounded by a black circle edged in white. This color pattern gives the illusion that the animal is wearing eyeglasses, hence the name Spectacled Porpoise.

Fins

The flippers on this species are small with rounded tips and are located close to the head. The fluke possesses pointed tips and a notch. The dorsal fin is larger than that of other members of this family. In male Spectacled Porpoises, the dorsal fin is taller and the leading edge and peak are both rounded. In females, the dorsal fin is lower and more triangular in shape, with a straight leading edge.

Behavior

The Spectacled Porpoise is considered to be a very shy and elusive animal. This timid creature is typically solitary and rarely spotted in groups of more than two individuals.

Swimming Style

This porpoise is considered a fast swimmer and appears to be weary of boats. Consequently, this species is rarely, if ever, observed bow-riding. Similarly, the Spectacled Porpoise is seldom seen breaching.

Life History

Because this species is rarely observed, very little is known of its reproductive biology. However, calving season is believed to take place from late winter to early spring.

Diet

The primary diet of the Spectacled Porpoise is believed to be fishes and squid.

Distribution/Population

This species inhabits the cold temperate and subantarctic waters of the Southern Hemisphere, specifically the coastal waters of eastern South America. This porpoise is believed to be the only species known to live near offshore islands. This distribution suggests the Spectacled Porpoise may have a circumpolar range that includes the open sea.

Harms

Hunting of the Spectacled Porpoise by man has never been recorded. Accidental entanglement in gill nets is, however, a significant cause of death to this species. Killer whales are the only known natural predators of this porpoise.