Fennel has feathery leaves and open, umbels of yellow flowers. It was probably introduced by the Romans for culinary use, and is now a naturalised species of verges, waste ground and sand dunes.…

As its name suggests, Himalayan balsam is from the Himalayas and was introduced here in 1839. It now an invasive weed of riverbanks and ditches, where it prevents native species from growing.

Traditionally a coastal species, Lesser sea-spurrey has spread inland, taking advantage of the winter-salting of our roads. Its pink-and-white flowers bloom in summer.

The Natterer's bat can found across the UK, although it is a scarce species. It prefers to forage low down among trees, often taking prey directly from the foliage.

With a silvery body, and purple, pink and bluish streaks down its flanks, the rainbow trout lives up to its name. Popular with anglers, it is actually an introduced species in the UK.

A plump gamebird, the red-legged partridge is an introduced species that seems to have settled here with little problem. It can be spotted in its favoured open scrub and farmland habitats.

An introduced species, the rhododendron leafhopper is a striking mix of green and red, with a black stripe across its face. It can be found feeding on rhododendrons (also introduced) in Southern…

The carnivorous lifestyle of the round-leaved sundew makes this heathland plant a fascinating species. The round leaves have sticky, 'dew'-covered tendrils that tempt in unsuspecting…