Wildlife - Menai Strait

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The Menai Strait is the captivating submerged valley that separates Anglesey from mainland North Wales.  It is orientated north east to south west, and stretches for approximately 15 miles from Trwyn Penmon to Abermenai Point.  It encompasses numerous habitats, ranging from dynamic marine reefs to expansive sandy beaches and lofty sea cliffs.

The area forms part of the Menai Strait and Conwy Special Area of Conservation (SAC).  This is a designation which enables the protection of special habitat types and species (excluding birds) which are considered to be most in need of conservation at a European level.  The environmental conditions of the Menai Strait are unusual, inasmuch as it is sheltered from wave action but subject to rapid tidal flows which can reach speeds of 4 metres per second during spring tides. There is also much suspended matter in the water, which creates ideal conditions for filter feeders.

The Strait’s inner shores are dominated by bristle worms such as Spio filicornis. The limestone reefs are home to several rock-boring species including rock-boring sponges, piddocks and acorn worms.  Large colonies of breadcrumb sponges exist, accompanied by other reef dwellers including scorpion spider crabs, red-eyed velvet swimming crabs, butterfish, lumpsuckers, and conger eels.  The Straits are home to a wide variety of shore and wading birds, such as little egret, oystercatcher, curlew and redshank.  During some winters, internationally important flocks of common scoter have been observed, gathering to feed upon the plentiful populations of bivalve molluscs.  The nationally scarce dwarf eelgrass Zostera noltii is found in the area between Beaumaris and Lleiniog.  If you are lucky, you may catch a glimpse of a seal or harbour porpoise hunting and playing in the tidal races.

For a list of public toilets on the island, please see Isle of Anglesey County Council - public toilets