Dundalk Bay ( ga, Cuan Dhún Dealgan) is a large (33 km²), exposed

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

on the east coast of

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

. The inner bay is shallow, sandy and

intertidal The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species ...

, though it slopes into a deeper area 2 km from the transitional water boundary.Inner Dundalk Bay
Central Fisheries Board, Ireland. Retrieved on 29 September 2008. It is predominantly influenced by the sea, though several

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

s drain into the bay from the west. In the northwest corner of the bay, the Castletown River cuts through the intertidal zone and the smaller

River Fane The River Fane ( ga, Abhainn Átha Féan) is a river flowing from County Monaghan to Dundalk Bay in County Louth, Ireland. Course Originating in Lough Ross on the border of County Monaghan and County Armagh, and so of the Republic of Ireland ...

flows into the southeast corner. While the shores of the bay are largely made up of intertidal flats, there is a significant area of

salt marsh A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is domin ...

on the western shore. The catchment around the bay is of mixed agriculture and urban land use.

Special Area of Conservation

Dundalk Bay is a

Special Area of Conservation A Special Area of Conservation (SAC) is defined in the European Union's Habitats Directive (92/43/EEC), also known as the ''Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora''. They are to protect the 220 habitats and a ...

. Its important habitats are the intertidal sand and mudflats and the extensive saltmarshes. The area of sand, gravel and mud exposed at low tide amounts to over . These are rich in polychaete worms,

bivalve molluscs Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bival ...

and

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...

s which are the main food for the tens of thousands of waders, gulls and waterfowl that feed here. As many as 20,000 birds regularly feed here and the site is of national and international importance for bird populations, and has been designated as a Ramsar site. The saltmarshes are characterised by sea-purslane and common cord-grass, with common saltmarsh-grass, thrift,

red fescue ''Festuca rubra'' is a species of grass known by the common name red fescue or creeping red fescue. It is widespread across much of the Northern Hemisphere and can tolerate many habitats and climates. It is best adapted to well-drained soils in ...

, common scurvygrass, sea plantain and

sea rush Sea rush is a common name for several rushes in the genus ''Juncus'' and may refer to: *''Juncus kraussii'', native to the Southern hemisphere *''Juncus maritimus ''Juncus maritimus'', known as the sea rush, is a species of rush that grows on c ...

. On the seaward margin is much

glasswort The glassworts are various succulent, annual halophytic plants, that is, plants that thrive in saline environments, such as seacoasts and salt marshes. The original English glasswort plants belong to the genus ''Salicornia'', but today the glass ...

. There are also banks of pebbles and areas of shingle on the foreshore, with spear-leaved orache, sea mayweed,

sea beet The sea beet, ''Beta vulgaris'' subsp. ''maritima'' ((L.) Arcangeli.), is a member of the family Amaranthaceae, previously of the Chenopodiaceae. Carl Linnaeus first described ''Beta vulgaris'' in 1753; in the second edition of ''Species Plantarum ...

, sea rocket,

wild carrot ''Daucus carota'', whose common names include wild carrot, European wild carrot, bird's nest, bishop's lace, and Queen Anne's lace (North America), is a flowering plant in the family Apiaceae. It is native to temperate regions of the Old World ...

, sea holly, sea sandwort and sea radish, with some yellow horned-poppy and

lyme-grass ''Leymus arenarius'' is a psammophilic (sand-loving) species of grass in the family Poaceae, native to the coasts of Atlantic and Northern Europe. ''Leymus arenarius'' is commonly known as sand ryegrass, sea lyme grass, or simply lyme grass.

Rivers

Rivers which flow into Dundalk Bay:Dundalk Bay
Ask About Ireland * Several small flows from the Cooley Peninsula * Flurry River (a.k.a. River Ballymascanlan) * Castletown River ( Creggan River) - 45 km (28 miles) ** Tributary - Cully Water River (Falmore River, Dungooley River) - 23.3 km (14.5 miles) ** Tributary - Kilcurry River (aka Forkhill River) - 18.5 km (11.5 miles) * Rampart River, flowing through central Dundalk to join inner Dundalk Bay *

- 61.56 km (38.25 miles) *

River Glyde The River Glyde ( ga, an Casán) is a river in eastern Ireland, flowing from County Cavan to County Louth. Course The Glyde rises in the town of Bailieborough in Cavan, the upper reaches are sometimes known as the Lagan River, but after the Kil ...

- ** Tributary - River Dee -

References

{{coord, 53, 57, N, 06, 15, W, region:IE_type:waterbody_scale:500000, display=title Bays of the Irish Sea Landforms of County Louth Bays of the Republic of Ireland Estuaries of Ireland Ramsar sites in the Republic of Ireland