Donna Nook Grey Seal Colony
It is an amazing fact that Britain has nearly half of the world’s population of grey seals on its shore line. The Grey Seal also called the Atlantic seal Halichoerus grypus meaning Hook nosed sea pig, can be found on remote Scottish islands. There are four colonies of grey seals thriving along the east coast of Britain, namely the Farne Islands, Donna Nook, Blakeney and Horsey along the North Norfolk coast. They are one of our largest mammals and although huge to look at they are extremely nervy during their winter pupping season.
The reserve at Donna Nook is managed by the Lincolnshire Wildlife Trust and covers around six miles of coastline between Grainthorpe Haven in the north and Saltfleet in the south.
Grey Seals have to come ashore to breed and records show that they have been breeding at Donna Nook since the early 1970’s.
The females arrive at the breeding sites first and will usually give birth a day later. They give birth to just a single pup weighing approximately 15kg at birth. As mammals they feed their pups on their milk for the next three weeks. Their milk is 60%fat similar in consistency to that of condensed milk, consequently the pups can gain 2kg per day. The pups are born with a white silky fur coat which they keep for about three weeks until they are weened. Once their parent leaves them they start to moult and get their mottled waterproof coat. Now their mothers have left them they have to learn to live in the sea and fend for themselves.
Once the cubs have weaned from their mothers the mothers will mate before returning to the sea. The gestation period of the female Grey seal is 11.5 months, including a 3 month delay in the implantation of the fertilised egg. Female Grey seal can breed at around 4 years and males must be 3 – 8 years old.
In the wild, grey seal females live up to 40 years, while males live up to 30 years.
The Bulls can grow to over 3m in length and weigh more than 300kg. Cows are much smaller and about half the weight.
Unfortunately more than half of the pups born won’t survive their first year.
At Donna Nook the first pup to be born in 2017 was on Friday 13th October.
By the 21st October there were 57 Bulls, 46 cows and 13 pups, a week later the numbers had risen to 199 Bulls, 329 cows and 152 pups. Last year there were 1,959 seal pups born.
There are well signed and fenced paths for the public to see the seals, access to see this colony is from the Stonebridge car park. The seals especially the curious pups come right up to the fence.
The reserve is made up of mudflats and sand dunes and rich in birdlife, nearly fifty species of bird breed here regularly, but more importantly it is a popular spot for the passing migrants of which 250 species have been recorded.
What is quite remarkable about this reserve is that the Ministry of Defence operate an off shore bombing range and as such great care should be taken when the red warning flags are being flown although access to the dune area is accessible and not affected by the off shore flying.
To view the gallery 'left click' on the picture below
|
|
|
