IT SOUNDS like a manifesto pledge an extreme right-wing political party might adopt – protecting British interests by removing foreign immigrants.
But a cull of thousands of non-natives taking place around Gatwick Airport this summer will actually ensure more diversity in the area.
Ecologists are capturing and "humanely dispatching" bucket-loads of signal crayfish – a species native to North America.
It's difficult to feel too much sympathy because they are not the most charming of creatures.
They resemble slimy lobsters and eat almost anything they can get their greedy little pincers on, including other invertebrates, young fish and even other animals' faeces.
They are currently living in large numbers in pockets of thriving wildlife around the airport, having been introduced to the UK in the 1970s, and are threatening to wipe out the native white clawed crayfish.
They carry crayfish plague, which is deadly to the white clawed crayfish.
As part of a drive to achieve a bio-diversity award, Gatwick Airport's on-site ecologist, Rachel Bicker, has the unpleasant task of collecting signal crayfish in empty tins of spam and sending them on to the crayfish afterlife.
She said: "It sounds a bit BNP, doesn't it. But it's for the good of bio-diversity.
"These non-native species reduce the biodiversity by being here. It's a national thing which we are also doing here.
"Our vision is to get British wildlife back to what it was before bad agricultural practices were brought in.
"Lots of things were hunted to extinction and species were introduced which have unbalanced the ecosystem."
The cull will not threaten the presence of the signal crayfish on a global level.
They are the most widespread alien crayfish in Europe, having invaded and disrupted the ecosystems in 25 countries.
They are also classed as being of lowest concern on the International Union for Conservation of Nature "red list" of threatened species because of their vast numbers.
Miss Bicker works for JS Agriculture, which works alongside the Gatwick Greenspace Partnership that has been managing local wildlife for some 20 years.
The team hopes to achieve the biodiversity award, issued by the Wildlife Trust, by the end of the year.
Miss Bicker said: "These little pockets of land are little havens for wildlife and we are hoping to get native species back. Otters are the ultimate one. There have been sightings in Sussex but no confirmed ones here yet.
"We're hoping we can create a little resting place for otters and other animals as they migrate through the area, and hopefully they will stop and think: 'Hey, it's pretty cosy here,' and stick around."
