A pretty and distinctive little waterbird, the mandarin duck was introduced from the Far East as its name suggests. Oddly for a duck, it nests in trees, sometimes high above the water.

Cotoneaster was introduced to the UK in 1879 from Eastern Asia as an ornamental plant. It is now an invasive non-native species which is taking over valuable habitats including limestone…

Great mullein is an impressive, tall plant of waste ground, roadside verges and gardens. Its candle-like flower spikes rise from rosettes of furry, silver-green leaves.

The disc-shaped leaves and straw-coloured flower spikes of Navelwort help to identify this plant. As does its habitat - look for it growing from crevices in rocks, walls and stony areas.

The small pearl-bordered fritillary is a pretty orange-and-brown butterfly of damp grassland, moorland, and open woodland. It gets its name from the row of 'pearls' on the underside of…

The lime hawk-moth is a large, night-flying moth that can be seen from May to July in gardens, parks and woods. It is buff-coloured, with green patches on its scalloped-edged wings.

The muntjac deer was introduced into the UK from China in the 20th century. It has gained a stronghold in southeast England, where it can cause damage to our woods through browsing.

The red grouse is an umistakeable bird - plump and round, with a gingery-red body as its name suggests. Found on upland heathlands, it is under threat from the nationwide, dramatic loss of these…

The distinctive spiky, or 'bearded', green flower heads of wall barley appear from June to July and are easy to spot in an urban environment as they push their way up through pavements…