British bat makes incredible journey

http://www.bbc.co.uk/nature/25759149

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The first bat to cross the sea from the UK to Europe has been recorded, according to experts.

The tiny Nathusius' pipistrelle was first ringed in Blagdon, near Bristol, and was discovered nearly 600km away in the Netherlands.

Unfortunately it had died but its identification ring could solve a migration mystery.

Experts suggest this could be the first evidence that the bats migrate across the North Sea.

The bat was originally ringed in the UK by Daniel Hargreaves from the charity Bat Conservation Trust in 2012, at a lake in the south west of England.

Teddy Dolstra, from the Friesland Mammal Working Group, discovered its body during routine monitoring of a roost site on the north coast of the Netherlands at the end of last year.

The bat was found in a busy farm building used to store cauliflower and broccoli, where Mr Dolstra says they are known to hibernate between the pallets.

Nathusius' pipistrelles weigh between 6 and 15g and are about the size of a human thumb.

They were first recorded on the Shetland Islands in 1940 and have been known to breed in England and Northern Ireland since the 1990s.

But the migratory movements of these tiny bats have been largely unknown because they are too small to carry the kinds of tags fitted to birds and other larger species.

Surveys on the continent have confirmed that the pipistrelles travel great distances by comparing where they were initially ringed with other locations they were found.

The bats head south west across Europe in late autumn and winter, returning to eastern Europe the following spring.

They have also been recorded on oil platforms and boats in the North Sea but this is the first time one has been recorded on both sides of the continent.

"We have only ringed 34 bats at Blagdon lake so to receive a record like this is astonishing; it's incredible to think that this little bat has flown a distance of at least 600km, avoiding hazards like roads and wind turbines, and for it to safely cross the sea is remarkable," said Mr Hargreaves.

Dr Fiona Mathews from the University of Exeter is now analysing samples from the bat to try to confirm more details about its journey.

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