The numbers of inshore waterbirds using the waters of Mull, Coll and Tiree during the non-breeding season; an assessment of the area's potential for qualification as a marine SPA 2009
The aim of this report was to determine whether the inshore areas of Mull, or Coll and Tiree, or parts thereof, meet UK SPA Selection Guidelines in respect of the numbers of inshore waterbirds outwith the breeding season.
JNCC conducted line transect aerial surveys to collect data on inshore waterbirds in the waters around Mull, Coll, and Tiree during the non-breeding season. Four surveys were completed of the west coast of the Isle of Mull over three winters (2004/05- 2006/07). Five surveys were completed of the waters around the islands of Coll and Tiree over five winters (2003/04-2007/08). The species recorded were: greater scaup Aythya marila, common eider Somateria mollissima, long-tailed duck Clangula hyemalis, red-breasted merganser Mergus serrator, red-throated diver Gavia stellata and great northern diver Gavia immer.
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 in order to determine whether the areas, or part of them might meet the selection requirements under Stage 1 of the UK Site Selection Guidelines, as a Special Protection Area under the EC Birds Directive. The means of peak estimates of great northern diver numbers were 54 for the waters west of Mull, and 492 in the waters around Coll and Tiree. Peak estimated numbers of great northern divers in the Mull area exceeded the appropriate Stage 1 threshold (currently 50 individuals) for SPA qualification under the UK SPA Selection Guidelines in only one out of three winter seasons, although the mean of peak estimates did exceed the Stage 1 threshold. Peak estimated numbers of great northern divers in the waters around Coll and Tiree exceeded the appropriate Stage 1 threshold under the UK SPA Site Selection Guidelines in each of five winter seasons.
Resource type Publication
Topic category Environment
Reference date 2009·08·01
Söhle, I., O’Brien, S.H., Dean, B.J., Wilson, L.J., Webb, A. & Reid, J.B. 2009. The numbers of inshore waterbirds using the waters of Mull, Coll and Tiree during the non-breeding season; an assessment of the area’s potential for qualification as a marine SPA. JNCC Report No. 416, JNCC, Peterborough.
This report is based on surveys conducted by JNCC to collect data on inshore waterbirds in the waters around Mull, Coll, and Tiree during the non-breeding season between 2003/04 and 2007/08.
Communications, JNCC publisher
Limitations on public access No limitations
Use constraints Available under the Open Government Licence 3.0
Metadata date 2020·05·19
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