phocoena

Phocoena is a genus of small toothed whales in the family Phocoenidae, consisting of four living species of porpoises: the harbor porpoise (Phocoena phocoena), the spectacled porpoise (Phocoena dioptrica), the vaquita (Phocoena sinus), and Burmeister’s porpoise (Phocoena spinipinnis). Some classifications treat the Mediterranean porpoise as a subspecies of harbor porpoise (Phocoena phocoena relicta) rather than a separate species.

Description and ecology

Porpoises in the genus Phocoena are robust, compact toothed whales with a short, blunt beak and a rounded head. They typically measure about 1.4 to 2.0 meters in length and display a coloration range from dark gray to almost black on top with a lighter belly. They use echolocation to hunt for small fish, squid, and crustaceans. Social behavior is generally quiet and shy; individuals and small groups are common, with larger congregations observed in productive feeding areas.

Distribution

Harbor porpoises inhabit coastal temperate and subarctic waters of the northern hemisphere, while spectacled porpoises occur in cooler southern oceans. The vaquita is restricted to the northern Gulf of California, Mexico, and Burmeister’s porpoise ranges in the southeastern Pacific, from Peru to southern Chile. Habitat use tends to be coastal or in continental shelf regions, though some species venture offshore.

Reproduction and threats

Reproduction involves a gestation period around 9 to 11 months, with calves nursing for several months. Lifespans in the wild commonly reach 15 to 25 years. Conservation concerns vary by species, but threats include bycatch in gillnets, habitat degradation, and pollution. The vaquita is critically endangered, with only a small remaining population reported in recent assessments; other Phocoena species are listed as vulnerable or near threatened in many regions. Protective measures focus on bycatch reduction, fishing regulation, and habitat protection.