The annual seal count, carried out by the resident rangers, is triggered by the birth of the first pups. Rangers from the conservation charity spend two months each autumn monitoring the success rate of the breeding seals which is crucial to understanding how the seal population is faring.
Every year, over 1,500 pups are born on the islands, which is one of the largest Atlantic grey seal colonies in England with a population estimated at 5,000. The breeding season for seals on the Farnes sometimes starts as early as mid-September with the majority of pups born in November.
Grey seals are currently thriving on the Farne Islands. In 2014, 1,740 pups were recorded – the highest number since 1971. Then in 2015, the count rose by 7.8% to 1,876.
National Trust ranger, Ed Tooth says: “A lack of predators and a plentiful supply of sand eels and gadoids (cod) – which make up a majority of the seals’ diet – has contributed to the success of the colony.
“The seals have also selected a different location for their rookeries, the breeding sites for the seals. Previously more pups were born on the islands of North and South Wamses, but now many seals try to breed on Brownsman and Staple islands. This has resulted in mortality rates dropping, possibly because these islands offer better protection from storms and high seas.”
The rangers, who live on the Islands for nine months of the year, count the seals every four days, weather permitting. Once born, they’re sprayed with a harmless dye to indicate the week they are born; using a rotation of three or four colours allows the rangers keep track of the numbers.
This year the team is also contributing to a genetic study being carried out along the East Coast and in the Netherlands to determine if the Farnes colony acts as a ‘seeding colony’ for the Dutch seals.
Ed continues: “Waiting for the first seal pup to be born is always an exciting time of year. It’s impossible not to be fascinated by the bright white, fluffy, wide-eyed pups even though we will hopefully see more than 2,000 pups over the coming weeks. Although they are cute, in those four weeks after birth they’ll put on 30kg and be able to survive a winter in the North Sea.”
The pups are fed for anywhere between 16-21 days before they are weaned and then it’s another few weeks until they moult their soft white coats and their dense grey waterproof fur comes through.
The best way to see seal pups is from one of the boat trips that go from Seahouses and sail round the Farne Islands. Until the end of October, boats can still land on Inner Farne, where visitors can get off to explore the Island and enjoy its heritage and birdlife.