A familiar black bird of our lakes, ponds and rivers, the moorhen is widespread; look out for its large and untidy-looking nest on the water in spring. It can be distinguished from the similar…

These colourful little fish are a delight for snorkellers or shallow water divers to photograph, rarely being scared off by their presence!

A small colourful sea slug that can be found grazing on sea mats on the rocky shore and beyond the low water mark.

The thresher shark is a migratory species and passes through UK waters in the summer months. If you’re lucky, you might see this magnificent shark jump high out of the water in to the air.

False widow spiders are often the subject of unflattering headlines, but in reality they're unlikely to bite humans.

The largest of the UK wrasse species, the ballan wrasse with its striking patterning is a delight for any rocky reef snorkeller or shallow water diver!

A scarce but distinctive brown seaweed with curved, funnel-shaped fronds. It is a warmer water species at the northern edge of its range on the south coast of England.

Look out for the Daubenton's bat foraging over wetlands across the UK at twilight. Its flight is fast and agile as it skims the water's surface for insect-prey.

Arrowhead is an aquatic plant of shallow water and slow-moving waterways. In bloom over summer, it displays small, white flowers, but it is the arrow-shaped leaves that are most distinctive.

Curled dock is often considered a 'weed'. It can be found near water or on disturbed ground almost anywhere. It is similar to Broad-leaved dock, with which it can hybridise.