IBA Justification

The site was identified as important in 2009 because it was regularly supporting significant populations of the species listed below, meeting ('triggering') IBA criteria.

Populations meeting IBA criteria ('trigger species'):
Species Current IUCN Red List Category Season Year(s) Population estimate at site IBA criteria met
Roseate Tern Sterna dougallii LC breeding 2000 618 breeding pairs B1i, B2, C2, C6
Common Tern Sterna hirundo LC breeding 1999 610 breeding pairs B1i, C2, C6
Arctic Tern Sterna paradisaea LC breeding 1999 89 breeding pairs C6
Black Guillemot Cepphus grylle LC breeding 1998 83 individuals B2

The current IUCN Red List category may differ from that which was valid at the time of IBA criteria assessment (2009).

IBA Conservation

IBA conservation assessment
Year of assessment (most recent) State (condition) Pressure (threat) Response (action)
2009 favourable high medium
Was the whole site assessed? State assessed by Accuracy of information
yes population good

State (condition of the trigger species' populations)
Scientific name Common name Reference population Actual population Units % of population remaining Result
Larus argentatus 150 16 nests 11 not assessed
Sterna dougallii Roseate Tern 180 618 nests 100 favourable
Sterna hirundo Common Tern 108 610 nests 100 favourable
Sterna paradisaea Arctic Tern 2 89 nests 100 not assessed
Cepphus grylle Black Guillemot 40 83 individuals 100 favourable

Pressure (threats to the trigger species and/or their habitats)
Threat level 1 Threat level 2 Timing Scope Severity Result
Biological resource use fishing & harvesting aquatic resources - unintentional effects: large scale likely in short term (within 4 years) majority/most of area/population (50-90%) very rapid to severe deterioration high
Invasive and other problematic species and genes problematic native species/diseases - named species happening now small area/few individuals (<10%) moderate to rapid deterioration low

Response (conservation actions taken for the trigger species and/or their habitats)
Protected-area designation Management planning Other conservation action Result
Whole area of site (>90%) covered by appropriate conservation designation No management plan exists but the management planning process has begun Substantive conservation measures are being implemented but these are not comprehensive and are limited by resources and capacity medium
For more information about IBA conservation status, please click here

IBA Protection

Protected area (PA) PA designation PA area (ha) Relationship of PA with IBA Overlap of PA with IBA (ha)
Rockabill to Dalkey Island SAC Site of Community Importance (Habitats Directive) 27,314 protected area overlaps with site 0
Rockabill SPA Special Protection Area (Birds Directive) 5,227 protected area contains site 2
Rockabill Island Refuge for Fauna 1 protected area contains site 1


Habitat (IUCN level 1) Habitat detail Extent (% of site)
Shrubland Scrub -
Artificial/Terrestrial Other urban and industrial areas -
Marine Neritic -
Marine Coastal/Supratidal -
For more information about the IUCN Habitat classification, please click here.

Land use

Land-use Extent (% of site)
urban/industrial/transport -
nature conservation and research -

Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Rockabill. Downloaded from on 03/03/2024.