Seabirds are facing a “storm of decline” in Scotland’s coastal areas, according to new research.

The populations of birds such as the guillemot and kittiwake have fallen by as much as 63per cent since 2000, the RSPB said.

Now scientists have fitted the birds with “sat nav” devices to try to understand why the population is falling.

Initial results suggest the birds are flying hundreds of miles further than thought to find food.

The RSPB said the change could indicate that the population is falling because food supplies are getting scarcer. A study of birds living on the northern islands of Scotland found some were flying as far south as Dundee – some 217 miles – to find the sandeels and other small fish they feed on.

The Future of the Atlantic Marine Environment RSPB-backed project traced the birds’ flight patterns using GPS technology, while a separate study by the RSPB found Scottish seabirds were “in big trouble”, with populations in Orkney and Shetland in decline.

The charity said the fall in numbers in the so-called “seabird cities” could indicate “continuing problems” for the seabird population more widely.

At Troup Head on the Banff coast, guillemots have declined from nearly 40,000 birds in 2001 to barely 14,000 this year.