Native oysters are a staple of our seas and our plates - but our love of their taste has lead to a sharp decline all around the UK.

The large, dark grey water shrew lives mostly in wetland habitats. It's a good swimmer that hunts for aquatic insects and burrows into the banks.

A tall and hairy plant, Great willowherb displays pretty pink-and-cream flowers. It can be found in damp places, such as wet grasslands, ditches and riversides.

The Marsh helleborine is a beautiful orchid of fens, wet grassland and dune slacks. Growing in profusion in places, look for reddish stems and white-and-pink flowers.

The delicate, tube-like, violet-blue flowers of Skullcap bloom from June to September in damp places, such as marshes, fens, riverbanks and pond margins.

As its name suggests, Water dock likes damp places, such as the egdes of canals, ponds and rivers. It is a tall plant with large, greenish flower spikes.

The Welsh poppy is a plant of damp and shady places, roadsides and hillsides. It is also a garden escapee. It flowers over summer, attracting nectar-loving insects.

The bar-tailed godwit winters in the UK in the thousands; look for it around estuaries like the Thames and Humber. In spring, the males display arresting breeding plumage, with brick-red heads,…

Pellitory-of-the-wall is a small to medium-sized herb that frequently grows from cracks in old stone walls, pavements, cliffs and banks, and churches and ruins.