Yellow corydalis is a familiar 'weed' of gardens, walls and rocky places. It is a garden escapee in the UK, so is not a native plant. Try choosing natives for your garden to prevent…

These non-native limpets arrived from America in the 19th century and are now widespread in the UK. They form stacks and have a specially adapted shell which, when flipped upside down, looks like…

A handsome gamebird, the pheasant is an introduced species that has settled here with little problem. It can be spotted in its farmland and woodland habitats, although you'll probably hear…

As it names suggests, the common crossbill has a large bill that is crossed at the tip - perfect for picking the seeds out of pine cones. Look for it in conifer woodlands, mainly in the north and…

Herb-Paris has four oval leaves set in a cross, with an understated crown of yellow-green flowers rising from the middle. This makes it quite a distinctive plant of ancient and damp woodlands on…

The bluefin tuna is a highly migratory fish which roams the oceans. This species will cross oceans, travelling between the Mediterranean Sea and the Gulf of Mexico. They are speedy swimmers,…