The waters, foreshore and low-lying land of the Exe Estuary are of international importance for wintering wildfowl and waders. Many rare species of plant occur too, whilst the sandbanks and mudflats support communities of invertebrates that are of national significance. The site also contains key features of geological interest and has been the subject of considerable scientific research.
The Estuary runs south-eastward for about 4 km from Exeter to the junction of the Exe and Clyst Rivers. Here it broadens, being over 2 km wide in places, and runs for a further 7 km to Exmouth, where it is sheltered from the sea by the sand ridge of Dawlish Warren. The northern half of the estuary is flanked by reclaimed agricultural land, sewage works, reedbeds and the Exeter Canal. The soil is alluvial, derived from a variety of Devonian, Carboniferous and Permian rocks.
Over 10,000 wildfowl and 20,000 waders winter on the Estuary, which regularly supports over 1% of the European population of species such as dark-bellied Brent goose Branta bernicla bernicla, wigeon Anas penelope, ringed plover Charadius hiaticula and black-tailed godwit Limosa limosa. At about 250 birds, the flock of wintering avocets Recurvirostra avosetta is presently the largest in Britain.
Reclaimed land within the site is used by water birds at high tide, and also provides nesting and feeding habitat for other bird species. The largest portion is the Exminster Marshes, a series of fields drained by dykes and ditches, which in turn carry a rich flora and fauna including several plants rare in Devon such as parsley water-dropwort Oenanthe lachenalii, flowering rush Butomus umbellatus and frogbit Hydrocharis morsus-ranae, and a wide variety of dragonflies including the nationally uncommon ruddy darter Sympetrum sanguineum and hairy dragonfly Brachytron pratense. The Marshes are bounded by the Exeter Canal, and both the Canal and the Estuary in its upper reaches are fringed by beds mainly of common reed Phragmites australis which form an important area for several species of birds, notably warblers.
Below the reedbeds there is a transition to saltmarsh. Here club-rushes Scirpus spp. and sea rush Juncus maritimus are characteristic of the upper levels, with cord-grass Spartina spp. bordering these and increasing in extent lower down the Estuary. Below the saltmarshes and exposed at low tide, there are extensive areas of sand and mud. Some central banks are bare, and the remainder have only a sparse vegetation, but that vegetation consists largely of eelgrass Zostera spp. and green seaweed Enteromorpha spp., which are favoured foods of some wildfowl. Burrowing invertebrates are found in most of the sandbanks and mudflats, providing food for many fish and birds. Characteristic species include lugworm Arenicola marina, peppery furrow shell Scrobicularia plana, Tellins Macoma , Donax , Tellina, common cockle Cardium edule, razor shell Ensis siliqua, sea potato Echinocardium cordatum and masked crab Corystes cassivelaunus. Beds of mussels Mytilus edulis are important feeding grounds for oystercatchers Haematopus ostralegus. The Estuary is the only British locality for the polychaete worm Ophelia bicornia which occurs mainly on Bull Hill Bank. The foreshore rocks towards Orcombe Point are notable for the abundance of bivalve molluscs which bore into the soft sandstones. Here also occur colonies of the honeycomb worm Sabellaria alveolata.
The Orcombe rocks are a key geological feature which display an excellent coastal section in the sandstones, siltstones and mudstones of the Permian Exmouth Formation. These fluvial sandstones show a variety of trough and planar-tabular cross-bedding indicating that the rivers which deposited these sediments flowed towards the north. Mudstones represent deposition in fluvial overbank (flood plain) and playa-like environments, and they contain rare plant fossils. This is an important site for the elucidation of Late Permian environments, and is also of general geomorphological importance for the study of sedimentation processes.
This site is currently under consideration for inclusion in the new UK MPA network. Having marine components does not automatically qualify a site to be part of the new MPA network. As such, the marine components of this site, as well as the management efforts, are being evaluated. Check out our MPApedia page on the UK for more information!
For general information on Exe Estuary Site of Special Scientific Interest (regardless of MPA status), click here.
Contacts & Resources
Original data record from World Database on Protected Areas (WDPA) via ProtectedPlanet.net [view record on site].