by VK Freelance

Created on: July 13, 2009

Harbor porpoise

Appearance: The harbor porpoise is one of six species of porpoise, and is actually one of the smallest ocean mammals at about 1.4 m to 1.9 m (4.6-6.2 ft). It may be small but it is stocky and robust. It has a rounded snout with no beak with 44 to 54 teeth in its mouth. They are usually speckled very dark gray, or brown with a much whiter underside.

The females are usually heavier than the males and weigh in at about 76kg or 167 pounds.

Where found: The harbor porpoise is found in the cooler shallow waters of the northern hemisphere - such as France, Spain, UK, Ireland, Norway

Temperament: The harbor porpoise is shy, so often hard to find - it can prove to be elusive, unlike many other sea mammals such as dolphins which may approach your boat. They usually stay near the surface, but can dive deep more than 200 meters or 655 feet. However they need to come up for air about every 25 seconds, when they do so, they make a distinctive puffing noise, like a sneeze.

Diet: The harbor porpoise will eat small non-spiny fish such as herring, whiting, sprat, cod, sardines and Pollock. For it's small size, the harbor porpoise seems to need a large amount of food everyday - about 10% of it's body weight, to survive.

Conservation: The harbor porpoise is not on the endangered species list, but is one of the most frequently hunted ocean mammals. They are still numerous, but not as much as they once were and substantial numbers are taken from Greenland for their use of food or oil. They often get caught in other fishing nets and drown, plus the destruction of habitat and boat traffic have all led to the decline of their population, so The World Conservation Union currently lists harbor porpoises as a vulnerable species.

Predators: Apart from humans, predators include the white shark and Orcas and in places with a dwindling food supply, bottle nosed dolphins have been known to kill a harbor porpoise to stave off competition.

Breeding: The harbor porpoise will reach sexual maturity at about 4 years old and has a gestation period of 11 months. The offspring are about 30 inches in length or 80cm and weigh 14 to 22 pounds or 6.4 to 10kg. There usually has to be an interval of 2 years between calving as each calf will nurse for up to 8 months.

Captivity: A few harbor porpoises have been taken into captivity but they have a tendency not to survive, they prefer to live in small groups or pairs although up to 100 have been seen in one place, actively feeding. Obviously due to the large amount of food they need, living in large groups in impractical.

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