COUNTRYSIDE COUNCIL FOR WALES
SITE OF SPECIAL SCIENTIFIC INTEREST: CITATION
ANGLESEY LLYN MAELOG
National Grid Reference: SH326729
Site Area: 35.9 ha
Llyn Maelog has been selected for its biological interest as an example of an eutrophic (nutrient rich) lake. The lake lies in a shallow basin in boulder clay with outcropping igneous intrusions and Ordovician sandstones and conglomerates at the northen end.
Llyn Maelog supports an aquatic vegetation characteristic of a nutrient rich water body with species such as spiked water-milfoil Myriophyllun spicatum, horned pondweed Zannichellia palustris and rigid hornwort Ceratophyllum demersum. Eight species of pondweed Potamonaceae have been recorded including perfoliate pondweed Potamogeton perfoliatus blunt-leaved pondweed Potamogeton obtusifolius and lesser pondweed Potamogeton pusillus. The shallow water margins, the main zone of plant growth, support both widespread plants such as shoreweed Littorella uniflora and the nationally scarce species, needle spike-rush Eleocharis cicularis and autumnal water-startwort Callitriche hermaphroditica.
Much of the lake is fringed by common reed Phragmites australis; this forms an extensive reed bed at the southern end. Reedswamp characteristically includes few other species but yellow loosestrife Lysimachia vulgaris and the locally uncommon greater spearwort Ranunculus lingua occur here. Lesser water-plantain Baldellia ranunculoides and flowering-rush Butomus umbellatus are other uncommon plants which occur within the mergent fringe. Reed canary-grass Phalaris arudinacea and red fescue Festuca rubra are locally dominant in parts of the site, and dry dune grassland occurs along the roadside.
Llyn Maelog is of local interest for its wintering wildfowl particularly pochard, and for its breeding bird community. Wader species including oystercatcher and golden plover overwinter on the peripheral grassland. The site supports a range of breeding waterfowl and other birds including black-headed gulls which nest on small islands within the lake, and reed warbler, a local species of reed beds. Bittern has bred here in the past.
Freshwater mussels are recorded from the lake.