Look out for the white, umbrella-like flower heads of lesser water-parsnip along the shallow margins of ditches, ponds, lakes and rivers. When crushed, it does, indeed, smell like parsnip!

A common and diminutive fish, the minnow can be found in freshwater streams, rivers and lakes across the country. Look out for the dark stripe along its flank and the red bellies of the males.

A diminutive but aggressive predator, the three-spined stickleback hunts tadpoles and small fish. It is also known for fiercely protecting its nest of eggs until they hatch. Look for it in ponds,…

The Alder fly is a blackish invertebrate, with delicately veined wings that it folds over its body like a tent. It can be found near ponds and slow-flowing rivers; the larvae living in the silt at…

The sinuous otter is an excellent swimmer and can be seen hunting in wetlands, rivers and along the coast - try the west coast of Scotland, West Wales, the West Country or East Anglia for the best…

Introduced from Japan in the 19th century, Japanese knotweed is now an invasive non-native plant of many riverbanks, waste grounds and roadside verges, where it prevents native species from…

Reed sweet-grass is a towering grass with large, loose flower heads that can be found on marshy ground near rivers, streams and ponds. It can become invasive, but does shelter various aquatic…

The broad-bordered bee hawk-moth does, indeed, look like a bee! A scarce moth, mainly of Central and Southern England, it feeds on the wing and can be seen during spring and summer.

The mohawk-sporting caterpillar of this moth is often seen on shrubs and trees in late summer. As adults the orange-brown males fly by day, but the flightless females don't stray far from…