The numbers of inshore waterbirds using the Greater Thames during the non-breeding season; an assessment of of the area's potential for qualification as a marine SPA 2009
Aerial surveys of the Greater Thames were carried out over a total of 58 days over eight winter seasons between 1988/89 and 2006/07. These consisted of three strip transect aerial surveys (1988/89, 1989/90) and 20 line transect aerial surveys (2001/02-2006/07) conducted by JNCC, the Wildfowl & Wetlands Trust, and the Natural Environmental Research Institute, Denmark.
The species recorded were: common eider Somateria mollissima, common scoter Melanitta nigra, velvet scoter M. fusca, red-breasted merganser Mergus serrator, red-throated diver Gavia stellata, great northern diver G. immer, black-throated diver G. arctica, great crested grebe Podiceps cristatus and little gull Larus minutus.
The first part of this report describes analyses of these data to determine the numbers of birds present for each species. The second part of this report assesses those numbers against the appropriate guideline thresholds, to determine whether the area, or part of it, might meet the site selection requirements under Stage 1 of the UK Site Selection Guidelines as a Special Protection Area (SPA) under the European Union Birds Directive.
Based on the available data, an estimated 8,355 individual inshore waterbirds regularly use the inshore waters of the Greater Thames during the non-breeding season. This estimate does not exceed the appropriate Stage 1 threshold (20,000 individuals) for an assemblage of non-breeding waterbirds under the UK SPA site selection guidelines.
Resource type Publication
Topic category Biota
Reference date 2009··
Webb, A., Dean, B.J., O’Brien, S.H., Söhle, I., McSorley, C., Reid, J.B., Cranswick, P.A., Smith, L.E. & Hall, C. 2009. The numbers of inshore waterbirds using the Greater Thames during the non-breeding season; an assessment of the area’s potential for qualification as a marine SPA. JNCC Report No. 374, JNCC, Peterborough.
Aerial surveys of the Greater Thames were carried out over a total of 58 days over eight winter seasons between 1988/89 and 2006/07.
Communications, JNCC publisher
Limitations on public access No limitations
Use constraints Available under the Open Government Licence 3.0
Metadata date 2020·05·27
Metadata point of contact