Harbour Porpoise (Phocoena Phocoena) are one of the smallest mammals living in the sea. We have a resident pod on the south coast of Cornwall of between 8 and 10 individuals (they're a bit difficult to count!) They are quite hard to spot due to the small size of their dorsal fin so we tend to see them on relatively calm days. They are generally shy and don't interact with the boat as much as the dolphins might do.
How to identify a Harbour Porpoise:
Only 1.3- 1.8 metres in length
Grey/ dark brown coloured above, paler belly
Often makes a 'puffing' noise when at the surface breathing through its blowhole
Feeding and Distribution: Harbour Porpoises feed on herring, cod, sardines and pollack. As their name suggests, they are found close to the coastline and sometimes even venture up large rivers. They inhabit the North Pacific and the North Atlantic oceans. Threats and Conservation:
Due to its inshore distribution, the Harbour Porpoise was easy prey in the past so has been hunted. Now their biggest threat to survival is being accidentally caught in fishing activities, like so many other cetacean species.
Over fishing and climate change also pose a threat as they both deplete the porpoises' food source.
Living close to shore they are at risk of collecting pollutants, such as PCBs and pesticides, in their fat reserves. When they need to draw on their fat reserves, such as during periods of food shortage, any pollutants stored can have potentially toxic effects.
Research in Scotland has found that Bottlenose dolphins will attack and kill Harbour porpoises if there is strong competition for food. This can only be set to increase with constantly depleting fish stocks.
*All photos are taken by Orca Sea Safaris and/or their customers.