COUNTRYSIDE COUNCIL FOR WALES
SITE OF SPECIAL SCIENTIFIC INTEREST: CITATION
ANGLESEY CEMLYN BAY
National Grid Reference: SH331933
Site Area: 44.5
ha
Description:
The inner part of the bay is a tidal lagoon enclosed by a shingle ridge
forming a "bay head barrier" of storm beach shingle. Saltmarsh
communities occur around the lagoon. The shingle ridge, lagoon and brackish
pools further inland support a number of uncommon plant species including sea
kale Crambe maritima, sea radish Rapohanus maritimus, brackish
water-crowfoot Ranunculus baudotii and Ruppia maritima.
There
are colonies of common, arctic and sandwich terns which breed on low islands in
the main lagoon. The number of breeding pairs of each species fluctuates from
year to year but the site is particularly important for sandwich tern and often
holds over 1% of the British breeding population.
The water level in the lagoon is maintained by a weir which is
controlled to prevent the ternery from flooding at high spring tides. Wintering
wildfowl, notably wigeon, shoveler, goldeneye, teal, mallard and tufted duck
use the area.
Remarks:
(1)
The shingle
ridge and lagoon are leased from the National Trust and managed as a nature
reserve by the North Wales Naturalists' Trust.