Non native species introduced by humans to new areas are now one of the greatest and most dynamic threats to the diversity of the planet. But now scientists are taking action. In the Seychelles, more than 200 years of devastation by rats is coming to an end. In the Outer Hebrides, off the western coast of Scotland, seven hedgehogs were released to help control garden slugs. Now there are more than 6000, and they are decimating the populations of ground-nesting birds. In New York, the Asian longhorn beetle, widely believed to be the most destructive alien insect to ever reach the shores of America, now threatens Central Park and the forests of the eastern coast.
Films in this series