A survey of harbour porpoises (Phocoena phocoena) was carried out at five sites (North County Dublin, Dublin bay, Cork coast, Roaringwater bay cSAC and Galway bay) to derive density and abundance estimates. Single platform line-transect surveys were carried out on six days at each site between July and September 2008. Distance sampling was used to derive g(0), which is the density of harbour porpoises on the track of the vessel. Abundance estimates were calculated using the track-line as the sample and the sighting as the observation. During 28 survey days a total of 354 track-lines were surveyed for a total distance of nearly 20,000 km in seastate ≤2. From the 269 sightings of a total of 496 individual harbour porpoise were recorded. There were 13 sightings with a total of 171 common dolphins (Delphinus delphis), eight sightings of single minke whales (Balaenoptera acutoratrata) and one sighting of 20 bottlenose dolphins (Tursiops truncatus). Five sightings with a total of 18 dolphins were not identified to species level.
L o a d i n g
Overviewbiodiversitybiotacetaceanenvironmentirelandmammalmarinemarine faunanational parks and wildlife servicenpwsspecies distribution
Additional Information
KeyValue
Conforms To["The INSPIRE Directive or INSPIRE lays down a general framework for a Spatial Data Infrastructure (SDI) for the purposes of European Community environmental policies and policies or activities which may have an impact on the environment.", "http://www.opengis.net/def/crs/EPSG/0/4326"]
Contact Emaildatadelivery@housing.gov.ie
Contact NameDepartment of Housing, Local Government and Heritage
FrequencyOther
Guidhttps://data.gov.ie/dataset/a409d503-0c9c-44b6-b887-09e3addc9dc5
Harvest Object Ida16f2084-c835-450a-b37c-465fa4a6e978
Harvest Source Id01350574-268d-4abb-b9b4-8108224932c4
Harvest Source Titledata.gov.ie - Environment
Identifiera409d503-0c9c-44b6-b887-09e3addc9dc5
Issued2022-07-06
Language["http://publications.europa.eu/resource/authority/language/ENG"]
Modified2026-06-03T02:27:18
ProvenanceDuring each transect the position of the survey vessel was tracked continuously through a GPS receiver fed directly into a laptop while survey effort, including environmental conditions (sea-state, wind strength and direction, glare etc.) were recorded directly onto LOGGER software (©IFAW) every 15 minutes. When a sighting was made the position of the vessel was recorded immediately and the angle of the sighting from the track of the vessel and the perpendicular distance of the sighting from the vessel recorded. These data were communicated to the recorder in the wheelhouse via VHF radio. The angle was recorded to the nearest degree via an angle board attached to the vessel immediately in front of each observer. Accurate distance estimation is essential for distance sampling. At some sites during each survey an orange buoy225mm in diameter was towed 200m astern of the observers’ position on the survey vessel. This provided reference point against which to estimate distances.
The location data in this shapefile was collected in Roaringwater Bay candidate SAC between July and September 2008.
Publisher NameDepartment of Housing, Local Government and Heritage
Publisher Urihttps://data.gov.ie/organization/department-of-housing-planning-community-and-local-government
Spatial{"type":"Polygon","coordinates":[[[-10.650444030762, 50.807923689449],[-10.650444030762, 55.993470564449], [-5.289115905762, 55.993470564449], [-5.289115905762, 50.807923689449], [-10.650444030762, 50.807923689449]]]}
Temporal End2008-09-30
Temporal Start2008-07-01
Theme["http://publications.europa.eu/resource/authority/data-theme/ENVI", "Environment"]
Urihttps://data.gov.ie/dataset/a409d503-0c9c-44b6-b887-09e3addc9dc5