In winter it is important for wildfowl, including whooper swans. Llyn Cefni , which is also a Welsh Water reservoir, covers 175 acres in central Anglesey. It lies on rolling farmland and is fringed by conifer plantations, although large areas have recently been felled. It comprises two inter-connected lakes divided by a disused railway line. It is leased by the Cefni Angling Association, which stocks 3,000-4,000 brown and rainbow trout annually to supplement the naturally spawning brwon trout population.
Fishing is by fly only.
The average catch per visit is one fish of 1.25 lbs. Llyn Coron is a shallow, rich 70-acre lake lying at the inland end of the Aberffraw dune system, which gives it an unspoilt, tranquil character. It is approached by a minor road which follows the River Ffraw from near Aberffraw village. Llyn Coron supports a good stock of brown trout and sea trout, which run up the River Ffraw into the lake.