Mae'r rhywogaeth yma o siarc main a chain i'w gweld yn aml yn agos at y lan o amgylch ein harfordiroedd a gall dyfu i fod hyd at 6 troedfedd o hyd.

A breeding bird of fast-flowing, upland rivers, the grey wagtail can also be seen in lowland areas, farmyards and even towns in winter.

Tansy is an aromatic plant of rough grassland, riverbanks and verges that has button-like, yellow flower heads. It is the main foodplant of the rare Tansy Beetle, now found at only two places in…

The common octopus is a highly intelligent, active predator. It even has a secret weapon - special glands produce a venom that it uses to incapacitate its prey!

Mae'r siarc main yma’n cael ei enw o'r pigau o flaen ei asgell ddorsal. Gall ddefnyddio'r pigau yma i amddiffyn ei hun drwy gyrlio mewn bwa a tharo ysglyfaethwr.

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.

The porbeagle shark is a member of the shark family Lamnidae, making it one of the closest living relatives of the great white shark.

The soft, downy look of Yorkshire-fog makes it an attractive plant, even if it is considered a weed of cultivated land! It is also attractive to the caterpillars of the Small Skipper butterfly as…

The male purple emperor is a stunning butterfly with a brilliant purple sheen. Look for it feeding around the treetops in woodlands, or on damp ground, animal droppings or even carrion in the…