Be on the lookout for puffing porpoises
Welcome to our new column. Each month the Community of Arran Seabed Trust (COAST) will be bringing our readers family friendly stories and facts about Arran’s sea life. Here is their first report.
When David Nairn from the Clyde Marine Mammal Project sailed into Arran’s waters a few months ago, he knew he was on to something: ‘We never dreamt there would be so many porpoises around Arran. The Marine Protected Area could be so important for the conservation of this species in the Clyde’. A small pod has taken a liking to the waters off the Holy Isle lighthouse and a real ‘porpoise soup’ has been found off our south west coast, in the Kilbrannan Sound. But it’s not all fun and play for porpoises. They need to eat up to 10 per cent of their body weight every day to cope with our cold Atlantic waters.
These clever creatures make click sounds that bounce off objects, allowing them to echo-locate sand eels, mackerel, shrimps or octopus to feed on. This also allows David’s hydrophone to find out where and how many there are and explore their behaviour. But this also makes them highly vulnerable to noises from powerboats or military activities. A female will give birth to one calf at a time, which is half her size. It is rushed up to the surface for its first ‘puff’, the sound it makes when breathing air, and then swims by her side to suckle. Sadly, chemical pollutants are passed from mother to calves through their milk. Porpoises are shy animals and their triangular dorsal fins are difficult to spot in choppy seas. With a blunt rounded head and shape, they are smaller and chubbier than dolphins. One of the smallest cetaceans on earth, they are normally about the size of a small human adult. Grab your binoculars and set sail or find a good vantage point on the shore on a calm day. Look out for diving seabirds like gannets as there could well be feeding porpoises beneath the waves and remember to post your sightings to www.clydemarinemammalproject.org. Their sailing research boat, Saorsa (Freedom), will be back to study porpoises in our Marine Protected Area in March. For more information contact: info@arrancoast.com