The natural history story of the UK's most famous invader - the grey squirrel. Read more
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1. Grey Squirrel
The natural history story of the UK's most famous invader - the grey squirrel.
2. Japanese Knotweed
Does Japanese knotweed deserve its place as the most hated plant in the UK?
3. Harlequin Ladybird
Derek Mooney finds out how the harlequin ladybird became the UK's fastest invader ever.
4. Ring-necked Parakeet
How invasive is the ring-necked parakeet?
5. Ash dieback fungus
How do we protect our native wildlife from invisible invaders like the ash-dieback fungus.
