Mae’r dyfrgi hyblyg yn nofiwr ardderchog a gellir ei weld yn hela mewn gwlybdiroedd ac afonydd ac ar hyd yr arfordir – rhowch gynnig ar arfordir gorllewinol yr Alban, Gorllewin Cymru, y West…

This crab is common around all of the UK. If you've ever been rockpooling or crabbing, it's probably the shore crab that you've met.

Look for the wood warbler singing from the canopy of oak woodlands in the north and west of the UK. Green above, it has a distinctive, bright yellow throat and eyestripe.

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.

Their long narrow shells are a common sight on our shores, especially after storms, but the animals themselves live buried in the sand.

The last thing you’d expect this extraordinary creature to be is a fish!

This bog-loving butterfly is mostly found in the north of the UK, where it takes to the wing in summer.

Only a few pairs of snow bunting breed here, so look out for this striking black-and-white bird in winter around Scotland, the North West and the East coast of England.

The small, brown Dartford warbler is most easily spotted when warbling its scratchy song from the top of a gorse stem. It lives on lowland heathland in the south of England, where it nests on the…

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.

The Atlantic salmon spends most of its life at sea, but makes an epic journey back to the river or stream in which it hatched to spawn. Look out for it in freshwater rivers in the north and west…