Monday, 1 March 2010

Grey Seals little competition to fisheries

It had been a while since I last visited the Grey Seals at Horsey, one of Norfolk’s finest wildlife spectacles. Setting out from Winterton we headed north through the dunes in sunshine before dropping down onto the beach and the lure of the water’s edge. It felt glorious; the warmth in the sun’s rays suggesting a change of season and it seemed as if we’d shrugged off the winter gloom for one last time. Of course, such are the vagaries of the weather that the sunshine proved to be short-lived, a bank of fog rolling in off the sea, dropping the temperature and coating hair and clothing with a sheen of moisture. The fog also reduced the visibility and our first view of the seals was an uncertain one. The bulky shapes of several dozen seals matched those of the rocks, positioned as sea defences to reduce the effects of the North Sea swell. The smell of the seals, however, was sufficient for us to resolve what we were looking at. As we drew closer, still keeping a respectful distance, some of the seals raised or turned their heads to get a better look at us. Content that we posed no threat, they returned to their slumber.

These seals spend a good proportion of their time hauled out during the first quarter of the year. They will have pupped back in November, the females producing a single calf high above the tide line. It is for this reason that the beach at Horsey is closed through into February, allowing the mothers to suckle their pups undisturbed. The pups, which increase in weight from 15kg at birth to 60kg at weaning – just 18 days later – have usually left the haul-out sites by the time that the adults begin their moult in February, so now is a good time to visit.

Our east coast Grey Seals have been doing well in recent years, part of a wider North Atlantic population, and perhaps contributing 2,000+ pups annually. Of course, it will be a good few years before this season’s pups breed themselves; the females do not become sexually mature until they are 3-5 years of age, the males 8-10.

Grey Seals in the southern part of the North Sea often feed close to the sea floor, ‘grazing’ on sandeels or adopting a ‘sit and wait’ approach to snatch unwary cod, ling and other fish. This has brought them into conflict with fishermen (less so here than further north), who may regard them as a threat to their livelihood. Mind you, the numbers of fish taken by the seals are an order of magnitude less than the commercial catch limits operated in the North Sea.

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