Carlingford Lough 15 km long, narrow sea Lough, surrounded by mountains. The southern shore lies in County Louth, while the rest of the site is in Northern Ireland (UK site 274). This being a cross-border site the stated area of 4,660 ha covers the entire site on both sides of the border. Most of the birds occur along the northern shorline, within Northern Ireland. The sourthern (Republic) shoreline is used only occasionally by large numbers of some waterbird species. The data presented are based on overall counts carried out at the site overall. Additional data specific to the southern shoreline is included in the Ornithological information section.
Waterbirds which winter in important numbers are Branta bernicla (336 birds, 1.3% of flyway), Larus ridibundus (425 birds), Larus canus (401 birds), Calidris alpine (1168 birds, 1.3% of national population) Phalacrocorax carbo (110 birds) and Charadrius hiaticula (101 birds). Bird numbers are 5-year mean (1998-2002).