The toll of birds killed in oil disaster mounts as scientists find two new species of Britain's most common bat

NICHOLAS SCHOON

A tiny pipistrelle nestles in the hands of its captor after scientists revealed that there are in fact three species of Britain's most common bat living in these islands.

It was thought only one existed, but experts at Leeds and Bristol universities have found differences in their physical make up, DNA genetic material, and the frequencies at which they squeak out their echolocating pulses and mating calls - so high pitched that electronic equipment is used to hear them. One pipistrelle's sound radar works at 45,000 cycles per second, the other at 55,000. The two types number about 2 million bats and appear to mix quite happily, but do not interbreed. Kate Barlow, a Bristol University student, has also found evidence that the much rarer Nathusius pipistrelle, once thought to be a vagrant from the continent, is breeding here.