Sea slug
This large sea slug is anything but dull!
Sea spurge
As its name suggests, Sea spurge is found at the coast. It is an attractive plant that displays cup-shaped, greeny-yellow flowers and fleshy, grey-green leaves.
Sea-buckthorn
Sea-buckthorn is a spiny, thicket-forming shrub of sand dunes. It's native to the east coast of England but considered an invasive species elsewhere. It is most obvious in autumn when it is full of bright orange berries.
Sea-holly
The spiky, silvery leaves of Sea-holly give this plants its common name. Look for its beautiful, thistle-like, blue blooms on coastlines and sand dunes in summer.
Sedge warbler
In summer, the sedge warbler can be spotted singing from a reed or willow perch in wetlands across the UK. Males never sing the same song twice, adding new phrases to impress the females.
Selfheal
Selfheal is a low-growing, creeping plant that likes the short turf of grasslands, roadside verges or even lawns. Its clusters of violet flowers appear in summer.
Serotine
The serotine is one of the first bats to appear at night and can be seen around lamp posts chasing moths, or at treetop height. It likes to roost and hibernate in old buildings in the south of the UK.
Serrated wrack
This brown seaweed lives in the lower shore and gets its name from the serrated edges to its fronds.
Sessile oak
The Sessile oak is so-called because its acorns are not held on stalks like those of the familiar English oak. It can be found in woodlands mainly in the north and west of the UK.
Shag
Shag' is a very old name that means 'tufted' and refers to the small crest that this bird sports. Look out for it in spring and summer either diving for fish from the surface of the sea or nesting on coastal cliffs.
Shaggy inkcap
As its name suggests, the shaggy inkcap, or 'lawyer's wig', has a woolly, scaly surface to its bell-shaped toadstools. It is very common and can be seen at the road side, in parklands and even popping up in lawns.
Shanny
The shanny is a common sight in rockpools all around the UK. They are feisty little fish and have been known to bite when caught, so watch your fingers!