Atlantic grey seal pup numbers at the Farne Islands have reached a new record thanks to a good supply of food and lack of predators, the National Trust has revealed.
Over the last five years the overall number of seal pups have increased by 50 per cent (2,602) indicating a positive picture for this intriguing mammal.
The grey seal is a protected sea mammal with global numbers estimated to be around 300,000 half of which live in British and Irish waters.
The rangers, who live on the Islands for nine months of the year, count the seals every four days in the autumn once pupping season begins, weather permitting. Once born, they’re sprayed with a harmless vegetable dye to indicate the week they are born. Using a rotation of three or four colours allows the rangers keep track of the numbers.
Ranger Thomas Hendry said: “Once all the seabirds leave in late summer, our attention turns to the seals. The seal breeding season on the Farnes is usually mid to late September until December, with the majority of pups being born in October and November.
“We wait until the first pups are born and then begin the process of counting and marking all pups born on the Islands.
“A lack of predators and a plentiful supply of sand eels – which makes up about 70 per cent of the seals’ diet – has helped bolster our seal pup numbers.
“This new record for the grey seal colony is certainly a milestone and could be good news for the health of our seas around the islands, indicating a good food supply due to fishing being limited partly due to several protected areas of sea around the islands.
“Over the next few years we will monitor the effect of a growing seal population and to manage the island habitats accordingly.”
For the first time, following a successful trial last year, rangers have also used a drone to help make the count more accurate and less stressful for the seals.
Thomas continued: “The drone gives us an excellent view of the islands and from the clear images we can count the total numbers of seal pups on each island. As the footage is taken whilst we are spraying, we use the image counts to check against the numbers we get on the ground. It also allows us to see onto the smaller islands which are more challenging to land in
difficult sea conditions.”
The seals are born with bright white fluffy coats. Although the pups can swim at an early age they don’t normally leave the breeding colony until they have been weaned and after they have moulted their soft white coats. This happens when they are about two or three weeks old and their dense grey waterproof fur grows through.
The rangers have also noticed changes to the location of the rookeries (the breeding sites).
While more pups used to be born on the islands of North and South Wamses, now many seals try to breed on Brownsman and Staple islands which are both bigger and have higher
ground, therefore offering better protection from storms and high seas.
Seal pup numbers have also hit record highs at the charity’s Blakeney Point in Norfolk, where figures have reached 2,802 in this year’s count, versus 2,000 in 2014.
For more information about the Farnes visit www.nationaltrust.org.uk/farne-islands For information on how you can help support its work on the coast, visit https://www.nationaltrust.org.uk/appeal/coast-campaign-appeal