UK033
Isles of Scilly


IBA Criteria

Year of most recent IBA criteria assessment: 2007

Populations of IBA trigger species
Species Current IUCN Red List Category Season Year(s) of estimate Population estimate IBA Criteria Triggered
European Storm-petrel Hydrobates pelagicus LC breeding 2006 1,398 breeding pairs B2, C2, C6
European Shag Gulosus aristotelis LC breeding 2006 1,296 breeding pairs A4i, B1i, B3, C3
Ruddy Turnstone Arenaria interpres LC winter 1984-1985 940 individuals A4i, B1i, C3
Lesser Black-backed Gull Larus fuscus LC breeding 2006 3,335 breeding pairs A4i, B1i, B3, C3
Great Black-backed Gull Larus marinus LC breeding 2006 901 breeding pairs B3
Common Tern Sterna hirundo LC breeding 1999 96 breeding pairs C6
Common Tern Sterna hirundo LC breeding 2006 78 breeding pairs C6

Note: This table presents the IBA criteria triggered and the species that triggered then at the time of assessment, the current IUCN Red List category may vary from that which was in place at that time.

For more information about the IBA assessment process and criteria please click here


IBA Monitoring

Most recent IBA monitoring assessment
Year of assessment Threat score (pressure) Condition score (state) Action score (response)
2007 high very unfavourable medium
Was the whole site covered? Yes State assessed by Population
Accuracy of information good

Threats to the site (pressure)
Threat Level 1 Threat Level 2 Timing Scope Severity Result
Human intrusions and disturbance recreational activities happening now some of area/population (10-49%) slow but significant deterioration medium
Invasive and other problematic species and genes invasive non-native/alien species/diseases - unspecified species happening now majority/most of area/population (50-90%) moderate to rapid deterioration high

Condition of key/trigger populations (state)
Scientific Common TargetPop ActualPop Units Remaining Result
Hydrobates pelagicus European Storm-petrel 2130 1398 breeding pairs 66 unfavourable
Gulosus aristotelis European Shag 1200 1296 breeding pairs 100 favourable
Larus fuscus Lesser Black-backed Gull 3760 3335 breeding pairs 89 near favourable
Larus marinus Great Black-backed Gull 1000 901 breeding pairs 91 favourable
Sterna dougallii Roseate Tern 5 0 breeding pairs 0 very unfavourable
Sterna hirundo Common Tern 105 78 breeding pairs 75 near favourable

Conservation actions taken at site (response)
Conservation Designation Management Planning Conservation Action Result
Whole area of site (>90%) covered by appropriate conservation designation A management plan exists but it is out of date or not comprehensive Substantive conservation measures are being implemented but these are not comprehensive and are limited by resources and capacity medium
For more information about IBA monitoring please click here

IBA Protection

Protection status:

Protected Area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)
St. Martin's Sedimentary Shore Site of Special Scientific Interest (GB) 34 protected area contained by site 34
Shipman Head & Shipman Down (bryher) Site of Special Scientific Interest (GB) 40 protected area contained by site 40
Samson (with Green, White, Puffin & Stony Islands) Site of Special Scientific Interest (GB) 39 protected area contained by site 39
Pentle Bay, Merrick and Round Islands Site of Special Scientific Interest (GB) 43 protected area contained by site 43
Isles of Scilly Special Protection Area (Birds Directive) 89 protected area contained by site 402
Isles of Scilly Area of Outstanding Natural Beauty 1,600 protected area contains site 562
Isles of Scilly Ramsar Site, Wetland of International Importance 402 protected area contained by site 402
Isles of Scilly Heritage Coast 2,285 protected area contains site 562
Gugh Site of Special Scientific Interest (GB) 37 protected area contained by site 37
Eastern Isles Site of Special Scientific Interest (GB) 36 protected area contained by site 36
Chapel Down (st. Martin's) Site of Special Scientific Interest (GB) 33 protected area contained by site 33
Castle Down (Tresco) Site of Special Scientific Interest (GB) 58 protected area contained by site 58

Habitats

IUCN Habitat Habitat detail Extent (% of site)
Shrubland Heathland -
Grassland Mesophile grasslands -
Wetlands (inland) Mud flats and sand flats, Sand dunes and beaches, Shingle or stony beaches, Coastal lagoons, Standing freshwater -
Sea Open Sea -
Coastline Sea cliffs and rocky shores, Rock stacks and islets -
For further information about the habitat classification please click here.

Land use

Land-use Extent (% of site)
tourism/recreation -
For further information about the land use classification please click here.


Recommended citation
BirdLife International (2020) Important Bird Areas factsheet: Isles of Scilly. Downloaded from http://www.birdlife.org on 21/01/2020.