Phased, extended and subsumed SPAs


The UK SPA network has developed over two decades.  Because of improved knowledge of bird distribution and other factors, some sites have been enlarged, whilst others have been classified progressively.  This Appendix explains the UK approach to phased classifications, subsumed sites and extended sites.

'Subsumed' sites

Some early SPAs have been significantly extended.  As the Birds Directive contains no provision for de-classification, however, it has not been possible to declassify a small site simultaneously with the classification of the extended, surrounding area.  Some SPAs have therefore been 'double designated'; that is, the area of the original classification has been included within the new extended site classification.  In such cases, care has been taken to avoid double counting the areas, and bird populations, for both reporting purposes and in this review.


This approach has been adopted for the following SPAs:



Extended sites


A number of early SPAs (until about 1986) were based on sites within public ownership i.e. National Nature Reserves.  These early classifications also focused on areas supporting large numbers of birds, rather than an analysis of species' needs.  Such sites included Moor House, Rum, Skomer and the Ribble Estuary (1982), Derwent Ings and the Farne Islands (1985), and Grassholm and Rockcliffe Marshes (1986).  In some cases the boundaries of these early designations related rather more to land tenure, than to the ecological requirements of the birds.  These early SPAs have since been extended to more accurately reflect the ornithological interest.  For example, the 117 ha OrfordnessHavergate SPA (1982) now lies within the 2,417 ha AldeOre Estuary SPA (1996), and the 1,897 ha Rockcliffe Marshes SPA now forms part of the 30,706 ha Upper Solway Flats and Marshes (1992). 


This approach has been adopted where small initial classifications have subsequently been subject to major revision and enlargement.  A different approach has been adopted where relatively small areas have been added to large original SPAs.  In such circumstances the extensions have been treated, for reporting purposes, as part of the original classification.

Phased sites

Another approach has been adopted for a small number of very large sites which are ecologically a single entity, but where their sheer size has made the classification process too complex.  These sites have been sub-divided into a number of separate phases that have been classified separately.  Alternatively, some sites have been listed as phases where they are small, and perhaps widely separated, but have a very strong ecological connectivity or similarities. 


Ballochbuie, Scotland

Two phases: 12 June 1998 & 16 December 1998

Caithness Lochs, Scotland

Two phases: 1 February 1998 & 13 October 2000

Humber Estuary Flats and Marshes, England

Phase 1:  28 July 1994

Phase 2:  due in 2001

Lochnagar, Scotland

Two phases: 12 June 1998 & 16 December 1998

Mid-Essex Coast, Essex

Phase 1:  Dengie  24 March 1994


Phase 2:  Colne Estuary  28 July 1994


Phase 3:  Crouch and Roach Estuaries 24 March 1995 and 22 July 1998


Phase 4:  Blackwater Estuary  12 May 1995


Phase 5:  Foulness  4 October 1996

North Uist Machair and Islands, Scotland

Phase 1:  29 March 1999

Phase 2:  13 October 2000

Ribble and Alt Estuaries, England

Phase 1:  separate classifications of the Ribble Estuary   31 August 1982; and Alt Estuary   28 November 1985

Phase 2:  Ribble and Alt Estuaries  16 February 1995

[Ribble and Alt Estuaries extension due in 2001]

Rinns of Islay, Scotland

Feur Lochain  25 April 1990

Glac na Criche  25 April 1990

Rinns of Islay  27 November 1995

South Pennine Moors, England

Phase 1:  Peak District Moors (South Pennine Moors phase 1)  29 March 1996

Phase 2:  South Pennine Moors  26 June 1997

[South Pennine Moors extension  30 November 2000]

South Uist Machair and Lochs, Scotland

Loch Druidibeg, Loch a' Machair & Loch Stilligary  31 August 1982

South Uist Machair and Lochs  1 December 1997

The Wash, England

Phase 1:  The Wash  30 March 1988


Phase 2:  Gibraltar Point  5 March 1993

Wealden Heaths, England

Phase 1:  Thursley, Hankley and Frensham Commons (Wealden Heaths phase 1)  14 February 1994

Phase 2:  Wealden Heaths  16 March 1998