See the seals on our coast
It’s the season of the seal. The grey seal, or Halichoerus grypus, which translates unflatteringly as ‘hook nosed sea pig’ if you prefer.
It is now that these sea mammals will be visiting our largely unmolested beaches to haul out and breed. During November to January increasing numbers of these large animals – some bulls reach nearly three metres in length and weigh in at more than 300kg – use our shores to raise their young.
The cows which are smaller and lighter arrive first, already heavily pregnant from last year’s mating; they will give birth within a day or two of beaching. The bulls arrive shortly afterwards and set about establishing a loose territory within which a harem of females will be birthing. Most territorial skirmishes between rival males are somewhat half-hearted, duels being no more violent than clumsy chases across the beach or grumpy snarling and posturing, much like the antics adopted by professional footballers. However, occasionally a fierce contest does take place with the testosterone fuelled creatures squaring up and taking chunks out of one another in an effort to assert dominance. This all generally leads to just a small number of males monopolising the mating process.
Nearly 50% of the world population of grey seals is found in the UK, with the East Anglian coastline representing a significant breeding resource. The colony at Horsey and the surrounding area on the east Norfolk coast is perhaps the best known and most easily accessible rookery. Here, friendly volunteer wardens are on hand to provide information about the seals’ life-cycle and breeding behaviour.
The beach is subject to a voluntary closure during the winter months to allow the seals to breed without interference; the cows are very sensitive to disturbance, particularly by dogs, so providing a safe zone for them to nurse their young is essential to breeding success. Should the cow be disturbed, it exposes the pup to the risk of moving into a bull’s territory or the territory of another cow resulting in an attack leading to injury or death. Despite the beach being roped off, there are still excellent opportunities for observing and photographing the
“It is a tremendous experience – especially so for children – and an opportunity to get close to some remarkable wildlife”
seals up close, with some suckling their attractive, dark liquid-eyed pups within a few metres of the adoring public. These pups, which only weigh around 14kg at birth, are covered with a thick white fur but soon grow fat on the rich milk supplied by their mothers. This milk is so fat rich that the pups increase their weight by two kilograms a day. Unlike common seal pups which can swim within a few hours of birth, it takes three weeks of intense feeding and a few more to grow a waterproof coat before grey seal pups reach sufficient size and weight to take on the rigours of the North Sea. The cows do not themselves feed during the weaning process and will lose a significant percentage of body weight. They abandon their offspring once they judge them capable of an independent life, will mate with the dominant bull and then hungrily return to the cold depths that is their home.
Grey seals are quite extraordinarily adept swimmers and hunters. They hunt singly, diving to a depth of up to 70 metres to catch their favourite food, fish, squid and sand eels. Their ability to slow their heart rate while underwater allows them to stay submerged for several minutes at a time. They are almost exclusively sea dwellers, but I’ve watched individuals actively hunting along the tidal rivers of Norfolk, tearing into a hapless flatfish with relish. They hunt by sound as well as sight, which would seem to be invaluable in the murky waters surrounding our coastline. They are long lived animals, typically attaining an age of 25 to 30 years although first year mortality is very high with only 50% of pups making it beyond their first birthday.
If you get a chance over the next few weeks I can thoroughly recommend a visit to a grey seal breeding colony. It is a tremendous experience – especially so for children – and an opportunity to get close to some remarkable wildlife. At Horsey visitors are monitored and paths well marked and policed; at other sites it is essential you enjoy the seals while exercising caution.
There are a few simple rules to follow (Friends of Horsey Seals website – friendsofhorseyseals.co.uk):
• Stay at least 10 metres from the seals
• Look out for seals in the dunes and give them a wide berth
• Be careful – seals have a nasty bite
• Keep dogs on a lead
• Keep to marked viewing areas and respect the fencing
• Remember grey seals are wild animals and should not be approached
• Respect other visitors For more of Barry Madden’s brilliant nature musings and artwork, take a look online at: www.easternbushchat.blogspot.co.uk
The grey seal colony spread across a large part of the beach at Horsey, on the Norfolk coast.
Peeping out from among the dunes at Horsey.
The grey seal colony on the beach at Horsey, Norfolk.
A baby seal pup with its mother on the beach at Horsey.