The shy Harbour porpoise is in all of the coastal waters of the Northern Hemisphere, but most boaters probably never even know they’ve passed near them. Most often these small cetaceans seem to disappear when a boat nears. They even seem to vanish when you’re looking right at them. They blend into their environment so well that you may only hear the puffing sound of the quick breath they take. This is how they acquired the nickname the “puffing pig”. The pig part, well, I’m not quite sure how they managed that one, but puffing is easy once you’ve heard them.
Not only are they very shy, they are the smallest of the cetaceans reaching a mere 1.8 m or 6 feet maximum in length, and weighing in at a maximum of around 90 kg or just under 200 lbs.
Although they, as with other porpoises and dolphins, can reach higher speeds, Harbour porpoises tend to travel relatively slowly. They are seen usually in pairs or a family group of three or four, but seldom in larger groups.
While at anchor in a bay, a boater might hear the puffing and perhaps catch a glimpse of this porpoise’s small triangular shaped dorsal as the Harbour porpoise forages for small fish or squid to eat. They are usually seen in bays or estuaries, and there are known populations in a few specific locations.
Even though their actual numbers are unknown, it is known that the populations of Harbour porpoises have declined in certain areas. There have been mulitple strandings of these small cetaceans for unknown reasons. One of the most recent strandings was just outside of Victoria, BC. Unfortunately the eight porpoises died. One was a pregnant female which is quite disconcerting. Necropsies are in the process of being performed to determine the cause of death. And there are some deaths that cannot be attributed to any specific cause. With a very high metabolism rate, there is thought that Transient Orca, the meat eating variety, chase and exhaust these little animals.
Harbour porpoises in recent years, perhaps to avoid their own extinction, have been known to be the only cross breeding cetacean, so far. They have mated with Dall’s porpoises; usually the mother is a Dall’s and the father a Harbour porpoise. These Hybrid Dall’s / Harbour porpoises look very similar to a Harbour porpoise, but have other characteristics that are indicative of Dall’s porpoises, and are seen with Dall’s. There are a few that are documented and a few photographed.
Harbour Porpoise – Phocoena phocoena – Statistics:
up to 1.8 m (6 ft)
up to 90 kg (200 lbs)
Dark brown or grey back
(the lightest brown I have seen is in these photos)
Light grey to white on belly
Small roundish head
No beak and short mouth
Dark triangular dorsal fin