Mae’r pryf copyn tŷ cawraidd yn un o'n infertebrata cyflymaf ni, yn rhedeg hyd at hanner metr yr eiliad. Mae'r pryf copyn mawr, brown yma’n troelli gwe sy'n debyg i gynfasau ac yn…

This unmistakable moth spends the winter as an adult, tucked away in a sheltered spot like a cave or outbuilding.

This huge gull can be seen around most of the UK's coasts in summer, with some venturing inland in winter.

This well-camouflaged wader is a winter visitor to the UK, where it can be seen feeding on wetlands with a distinctive bobbing motion.

This large shrike visits the UK in small numbers each year, passing through on migration or spending the winter here.

This distinctive lark is a passage migrant and winter visitor to the UK, most often found along the east coast of Britain.

This small finch nests on moorlands and coastal crofts, spending the winter on the coast. The UK population has declined dramatically.

This small duck is an uncommon winter visitor to the UK, where they're usually found on lakes, reservoirs and gravel pits.

The herring gull is the typical 'seagull' of our seaside resorts, though our coastal populations have declined in recent decades.