It has a reputation for big fish, and in the recent past has produced very large brownies up to 9lb in weight. A photo of this fish can be seen on the Aber AA website.

It is extremely rich in insect life, and if you turn over a stone or look in the reeds you will see hundreds of hoglice. The bottom literally heaves with them. This explains why the llyn is often dour.

The lake also has a hatch of great red sedge, which can occasionally bring large fish to the surface during the summer months.

Fly fishing, spinning and earthworm fishing are allowed on Llyn Oerfa.