Conservationists have discovered that Little Terns clock up a huge amount of air miles during their annual migrations to Africa.
While studying the birds nesting on Chesil Beach in Dorset, it was revealed that two individuals, aged 15 and 16, had travelled more than 100,000 km during their lifespans. Considering the earth's circumference is around 40,000 km, this means these birds have flown the equivalent of more than two times around the world.
This is a particularly impressive feat when you consider their size. Little Terns typically weigh around 50 grams, which is roughly half the weight of a Blackbird.
Little Terns visit the UK's coastlines during the summer months, mainly congregating on southern and eastern shores, although colonies can also be found in north Wales, the Isle of Man and western Scotland.
When the summer comes to an end, the birds head down to Africa, sometimes travelling as far as South Africa.
The conservationists at Chesil Beach were able to calculate the Little Terns' age and mileage thanks to rings that had been fitted in 1999 and 2000 respectively.
Local bird ringer Steve Hales, who originally fitted the rings, commented: "Handling a bird which I had ringed as a week-old chick on the same beach 16 years ago was very rewarding. It emphasised just what an age some of our smaller seabirds can reach."
The Chesil Beach Little Tern project is now six years old and is being run by the RSPB in conjunction with the EU LIFE Little Tern Project.
Commenting on the news, Marc Smith, Dorset Wildlife Trust Chesil Centre officer, stated: "The colony has been very successful over the last three years, with well over a hundred fledglings. Hopefully we will be seeing many of these return in the years to come."
The RSPB estimates there are 1,900 breeding pairs of Little Terns visiting the UK annually. Remarkably fast flyers, these birds feed on fish and have an elaborate courtship ritual in which the male offers a fish to the female.