Aln Estuary

Site overview: Aln Estuary is an inshore site on the Northumberland Coast, which extends from the estuary mouth to the upper tidal limit. It is a small area covering just 0.39 km2. This estuary provides a vital link between the land and sea. Conditions in estuaries are typically more sheltered than other coastal areas; this creates an environment which can support some species that are not found in more exposed places. This estuary contains within it a rocky habitat which is relatively uncommon and is home to kelps, wracks, anemones, barnacles and sea squirts. These habitats also support a range of migrating and wintering water birds including gulls, dunlins and other waders such as redshanks, curlews, snipe and wigeons. Coastal salt-marshes and saline reedbeds, such as those found here, are recognised as being one of the world’s most productive ecosystems with many birds, juvenile fish, crustaceans and molluscs using marshes as nurseries. Salt marshes are also important in the fight against climate change. They are known to accumulate sediment and other organic matter at a rate that may keep up with sea level rise. They also provide carbon storage at approximately 10 times the rate measured in temperate forests.

Designation Status
Last Updated
6 June 2017
MPA Type
Marine Conservation Zone
MPA Purpose
to protect nationally important marine wildlife, habitats, geology and geomorphology


55° 23' 21" North,
1° 36' 57" West

Surface Area

0.39 km2
(0.15 mi.2 )


12.16 km
(7.56 mi.)

Iconic features protected by this site