The descriptive text, below the map, is from the Cornish Red Data Book (2009). The map on this web page depicts the organisms distribution and shows the records made pre-2000 and those made since.
Range & Status
Holarctic; in Britain and Ireland there are 2200 pairs breed; up to 197,000 in winter.
Cornwall: sporadic breeder (perhaps overlooked) on Bodmin Moor; a common winter
visitor to both freshwater and estuarine sites. Peak numbers have fluctuated between 1500 and 3000 in recent winters. Four sites have had peak counts of over 400 since 1985: Hayle, Walmsley Sanctuary, Colliford, Maer Lake and the Lynher, with Hayle consistently producing the largest counts. No sites are of National Importance. Isles of Scilly: it has bred here in the past; up to 69 in winter.
Habitat & Ecology
Feeds in flocks on middle reaches of estuaries, also by edges of shallow freshwater
Vulnerable to estuary development.
The main estuary sites are SSSI; all main sites are reserves or are afforded some form of protected status. Listed (long list) as a globally threatened/declining species (BSGR, 1995).
I.J. Bennallick, S. Board, C.N. French, P.A. Gainey, C. Neil, R. Parslow, A. Spalding and P.E. Tompsett. eds. 2009. Red Data Book for Cornwall and the Isles of Scilly. 2nd Edition.Croceago Press.
The Cornish Red Data Book Project was led by the Cornwall and Isles of Scilly Federation for Biological Recorders (CISFBR). The full text and species accounts (minus the maps) are available on the CISFBR website.