Red Bay SAC

Maerl megaripple

Red Bay  is situated off from the village of Cushendun, County Antrim and is the largest embayment on the east Antrim coast outside Larne Lough, with the mouth of the bay approximately 9.5km in width. It is sheltered from westerly winds by the Antrim coast and Glens of Antrim, but open to the east. Although the waters are fully marine, there are influxes of freshwater from a number of rivers which likely influence the salinity of some localised areas.

Red Bay SAC was designated based on the presence of Annex I feature sandbanks slightly covered by seawater at all times. The sandbanks of Red Bay SAC are unique in that they are dominated by 2-3m high mega-ripples of maerl, with live maerl, gravel, cobbles and coarse to fine sand on the crests and sub-fossil maerl in the troughs. The species of maerl found in Red Bay include Phymatolithon calcareum and Lithothamnion glaciale. The site is also known for supporting three extremely rare species of algae which are endemic to maerl; Cruoria cruoriaeformis, Halymenia latifolia and Gelidiella calcicola. Red Bay contains a relatively large area of the rare maerl biotope ‘Phymatolithon calcarium maerl beds with red seaweeds in shallow infralittoral clean gravel or coarse sand’, which is listed in Annex V of the EC Habitats Directive (Directive 92/43/EEC). Maerl beds are considered of high conservation interest and a priority feature.