Key Biodiversity Areas

Stour and Orwell Estuaries (2605)
United Kingdom, Europe

Site overview


KBA status: confirmed
Year of last assessment: 2007
National site name: Stour and Orwell Estuaries
Central coordinates: Latitude: 51.9567, Longitude: 1.1653
System: marine, terrestrial
Elevation (m): 0 to 15
Area of KBA (km2): 36.83565
Protected area coverage (%): 97.19
KBA classification: Regional
Legacy site: Yes

Site details


Site description: The Stour estuary straddles the eastern part of the Essex/Suffolk border and comprises five main bays, whilst the Orwell is a relatively long and narrow estuary. Both estuaries support extensive mudflats and saltmarshes. The IBA supports important numbers of wintering waders and wildfowl.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that was identified using previously established criteria and thresholds for the identification of Important Bird and Biodiversity Areas (IBAs) and for which available data indicate that it does not meet global KBA criteria and thresholds set out in the Global Standard.
Delineation rationale: First identified in 1989; boundary adjusted to that of the SPA in 2007, with additional areas at Barside Bay, and Fox's Marina - Orwell Bridge. 2000 area, 3379ha. SPA boundary used from JNCC; digitised at 1:10,000 scale. Additional area added on 1:50,000 maps. Renamed from Stour and Orwell Estuary 2007.

Habitats


Land use: agriculture | fisheries/aquaculture | nature conservation and research | urban/industrial/transport
IUCN HabitatCoverage %Habitat detail
Grassland5
Forest5
Marine Coastal/Supratidal5
Marine Intertidal43
Marine Neritic43

Threats


Threat level 1Threat level 2Threat level 3Timing
Agriculture & aquacultureMarine & freshwater aquacultureIndustrial aquacultureOnly in the future
Natural system modificationsDams & water management/useSmall damsOnly in the future
PollutionAgricultural & forestry effluentsNutrient loadsOngoing
Transportation & service corridorsShipping lanesOnly in the future
Human intrusions & disturbanceWar, civil unrest & military exercisesOnly in the future
Residential & commercial developmentHousing & urban areasOnly in the future
Natural system modificationsOther ecosystem modificationsOngoing
Human intrusions & disturbanceRecreational activitiesOngoing
Climate change & severe weatherHabitat shifting & alterationOngoing