ANOTHER LIFE:IT IS SOMETIMES good to be reminded that nature, like the sea, goes all round the island, and has some determined guardians. I like this month's report to the Irish Whale and Dolphin Group (www.iwdg.ie), about a young harbour porpoise that took a leap too far at Portstewart in Co Derry, where the River Bann rushes into the ocean. Surfing the swells that were pounding the shore, the animal was flung on to the rocky estuary breakwater and left wedged into boulders, upside down, some three metres above the sea.
A call to the local Coastal Zone Centre of the Northern Ireland Environment Agency alerted a vet and brought a three-man rescue team, plunging along through soft sand and dodging the spring tide’s violent surges. Eventually, perched on the slippery rocks and knocked sprawling by one especially huge wave, they managed to unwedge the porpoise and heave it into the water. It was stiff and bruised after some four hours of stranding, and was promptly washed back by the waves. But the third refloat saw it right itself to breathe, and start to swim rapidly seawards, even breaking exuberantly through the surf.
After all the dramatic whale sightings off our southern and western coasts last year, the northern waters this winter have provided really exceptional sightings of big groups of bottlenose dolphins. The average group recorded off Ireland is no more than half-a-dozen animals, but several large groups of 50 and 100 have been seen off Co Antrim, and a group of 90 off Donegal. There were similar records off the British shores of the Irish Sea and the Isle of Man, and one huge group off western Scotland’s Isle of Muck in December was estimated by several observers at between 100 and 500 animals.
Such record numbers are hard to explain, notwithstanding the “sanctuary” our territorial waters offer to whales, dolphins and porpoises (grouped together as cetaceans) by Charles Haughey’s direction in 1991. This added no new legal protection, but blessed the intensive work by the IWDG that has woken us all up to the heavy-breathing, beautiful wildlife round our shores.
It has also underlined a special responsibility in marine conservation. At sea, Bord Iascaigh Mhara has led development of warning “pingers” on fishing nets to reduce the bycatch of dolphins and porpoises: the EU has made these devices mandatory in the Celtic Sea, which holds some 80,000 of Ireland’s estimated 100,000 porpoises. In shore, these animals are key species of Special Area of Conservation (SAC) orders under the EU’s Habitats Directive.
Best known are the bottlenose dolphins of the Shannon Estuary, now one of the most thoroughly studied groups in Europe. More recently, the porpoises have been given SAC protection around the Blaskets, off Kerry, and in Roaringwater Bay, Co Cork. Now, the IWDG is pressing for four more SACs for porpoises and another for the dolphins.
A European Commission meeting in Galway next week, hosted by the Department of the Environment, will discuss the designation and management of SACs for all species and habitats. It will be given survey results by the IWDG that suggest Dublin Bay and north County Dublin have some of the island’s highest densities of porpoises (as keen-eyed Dubliners on the Dart or walking Howth Head might readily attest).
Galway and Donegal Bay would add representative ranges for the animal, in compliance with the Habitats Directive. Donegal Bay has already yielded impressive sightings of bottlenose dolphins, which, like the Shannon group, seem to be showing “site fidelity”; and another obvious candidate for a dolphin SAC is the coast on my own doorstep, from north Connemara to Achill, including Inishbofin and Inishturk.
ANY IRISH NOMINATIONS of further SACs have to be confirmed by the EU Commission, guided by marine science and ecology. But not all the threats to our smaller cetaceans are obvious. Some new ones for porpoises in particular are suggested as a possible cost of developments in renewable energy offshore wind farms, tidal and wave turbines, seaweed farming for biofuel.
At an IWDG conference on the porpoise last autumn, Dr Ben Wilson of the Scottish Association for Marine Science urged early dialogue with developers and more research into possible hazards. While the operating noise from offshore wind turbines is unlikely to bother porpoises, the percussive noise from driving piles for foundations is enough to damage hearing both of the mammals and their prey.
The small size of porpoises could cause them to be shredded in fixed tidal turbines, and a Scottish research model predicted that the whirling blades of 100 turbines could endanger up to 1,300 porpoises, especially in collisions in poor visibility or at night.
Like the “pingers” on fishing nets, new ocean installations of many kinds may need acoustic signals to spare our smallest cetaceans yet another human hazard.
EYE ON NATURE
Do mullet come up river for a change of diet, to breed, to rid themselves of sea lice, for Vitamin D from the sun?Tony Kelly, College Road, Cork
Mullet come into rivers and estuaries to feed on algae and sometimes at the outlets from food factories and abattoirs. They breed at sea.
The wendy house in my garden has been taken over by bees. Does anybody want them?
Phil McCooey, Killiney, Co Dublin
You will need the expert help of an experienced beekeeper to remove them.
My small garden pond has a filtering system and is netted. It is stocked with about 16 goldfish. I usually remove frogspawn to develop elsewhere. Recently I saw spawn in the pond, but two days later it was gone. What happened?Tom Hensey, Dublin, 9
The goldfish ate it.
Recently, near Harold's Cross Bridge, I saw a bird on the bank of the canal. Bigger than a starling but not as big as a seagull it had long red/orange legs, grey and white plumage and a long beak. What was it?G Monaghan, Parnell Road, Dublin, 12
It sounds like a redshank.
Michael Viney welcomes observations at Thallabawn, Carrowniskey PO, Westport, Co Mayo. E-mail: viney@anu.ie. Include a postal address.
