Alien species threat to native wildlife

AROUND 2,500 new species are predicted to arrive in Europe by 2050, including potentially hundreds to the UK, posing an existential threat to local plants and wildlife, scientists have said.

The number of non-native species of insects, arthropods and birds is expected to rise by 36 per cent around the world, according to an international team including University College London.

The researchers called for greater biosecurity measures to halt the devastation that invasive species such as Japanese knotweed can have on ecosystems.

Alien species are one of the main drivers of animal and plant extinction and are expected to cost the UK economy £3.4 billion in the next 20 years.

Marine species have been known to arrive attached to ships’ hulls or in their ballast water, while plants or fungi can hitch a ride on imported species, as is believed to have occurred with ash dieback.

Prof Tim Blackburn, of UCL, said: “Alien species will continue to be added to ecosystems at high rates through the next few decades, which is concerning as this could contribute to biodiversity change and extinction. But we are not helpless bystanders: with a global effort to combat this, it is possible to slow down or reverse the trend.”

One muntjac deer can look quite sweet in the autumn morning. But, as Shakespeare remarked of sorrows, they come not single spies, but in battalions. Then bang go the azaleas. The same applies to other successful invaders. The Egyptian goose looks like a decorative duck (which is indeed what it is, despite the name). But once a flock settles on a farmer’s land, they don’t leave much change out of a field of wheat. As we report today, the problem is growing. That is without taking account of newcomers not yet declared invasive alien species, such as the ring-necked parakeet, which does to an orchard what the Egyptian goose does to a cereal crop. Scientists say it is not too late to resist. Action now will prevent us drowning in a sea of Chinese mitten crabs, signal crayfish and slider terrapins.