Mae môr-gyllyll yn perthyn i ystifflogod ac octopysau – grŵp o folysgiaid sy’n cael eu hadnabod fel seffalopodau. Efallai eich bod chi wedi gweld y gragen fewnol sialcog, o’r enw asgwrn cyllell,…

The oak marble gall wasp produces brown, marble-shaped growths, or 'galls', on oak twigs. Inside the gall, the larvae of the wasp feed on the host tissues, but cause little damage.

Sand eels are a hugely important part of our marine ecosystem. In fact, the fledgling success of our breeding seabirds entirely depends on them.

The sanderling scampers about the waves looking for marine crustaceans, fish and even jellyfish to eat. It visits the UK in winter from its Arctic breeding grounds, but can also be seen as it…

The tops of Oarweed fronds can be spotted floating on low tides. Kelp beds are an important habitat, providing shelter for many other marine creatures.