Seal of approval: Farne Islands population boom gathers pace

National Trust rangers predict another bumper year as they begin their count of grey seal pups

They are one of the world's rarest seal species, officially endangered by a combination of water pollution, fishing nets and seaside tourism. But on the Farne Islands, off the Northumberland coast, the population of grey seal pups has increased by 57% in five years, with 2,737 born last year.

Rangers from the National Trust, which owns the islands, were predicting another bumper year as they began their pup count this week, taking aerial shots by drone and spraying newborns with special paint to keep tabs on their movements.