Lake Vyrnwy is man-made, with the dam that created it
completed in 1888. The village of Llanwddyn was submerged by the lake.
In dry summers, if the water level drops far enough, the ruins of the
old village reappear.
Birds that breed in and around the lake
include goosanders, common sandpipers, great crested grebes and
mallards. In the winter months, small numbers of teals, pochards and
tufted ducks can be seen, and nonbreeding cormorants are present all
year. Since World War II, 44% of the heather moorland has been lost in
the Berwyn Mountains, mainly to forestry and agriculture.
Despite this, these mountains, of which Lake Vyrnwy is a part, have the
largest remaining area of heather moorland in Wales. Because of this
loss, many of the birds that rely on heather moorland for breeding have
become scarce in Wales. These species include red grouse, merlin, hen
harrier and black grouse. Much of the reserve management here is aimed
at improving the heather to encourage these and other moorland species.
A lot of work was carried out on the reserve in the
1980s to ensure the survival of existing woodlands and to create
approximately 80 hectares (200 acres) of new woodlands.
birds that benefit from this work include pied flycatchers, redstarts,
wood warblers, great spotted woodpeckers, nuthatches and tawny owls. A
huge variety of flowering plants, mosses, ferns, fungi, lichens and
insects are associated with oak woodland. The exquisite purple
hairstreak butterflies of the woodland canopy can sometimes be seen from
the Garrison Hide.
The 2000 hectares (5000 acres) of commercial
forestry around the lake has created an additional habitat which is
exploited by several species of bird, such as the tiny goldcrest and the
widespread coal tit.
Some of the more unusual species seen in
the forest include goshawk, crossbill, siskin, buzzard, raven and
sometimes nightjar. Several species of orchid, including heath spotted
and greater butterfly orchids, may be found. Some of the damp rough
pastures are important breeding areas for butterflies such as the small
pearl-bordered fritillary. Damp pasture is also important for curlews
and snipe, while whinchats and tree pipits can be found on the drier
Review Lake Vyrnwy Nature Reserve.