Marine Mammal Distribution 2019 Reporting

This dataset shows the current distribution of marine mammals in Irish coastal and marine waters. The data were collected for the purposes of 2019 reporting under Article 17 of the EU Habitats Directive. Every six years, the Member States of the European Union are required to report on the conservation status of all habitats and species listed on the annexes of the Habitats Directive. This dataset presents work carried out by the National Parks and Wildlife Service and its associated entities as part of this reporting. Underlying Data: The relative abundance of Atlantic White-sided Dolphin, Beaked Whale, Blue Whale, Bottlenose Dolphin, Common Dolphin, Fin Whale, Humpback Whale, Killer Whale, Risso Dolphin, Sperm Whale, Striped Whale and White-beaked Dolphin recorded by the Irish Whale and Dolphin Group (IWDG) between 2005 and 2011 conducted via visual survey effort focused on a 90-degree arc ahead of the ship used for the observation. Surveyors scanned the area by eye and using binoculars (typically 10X40 or 8X50). Data Lineage: This Atlas presents data collected during the IWDG ISCOPE I and II projects, the IWDG/GMIT Marine Mammals and Megafauna in Irish waters project, the IWDG Ferry Surveys Programme and the IWDG casual and effort-based sightings scheme between January 2005 and January 2011. A single marine mammal observer (or up to three observers, in the case of IWDG ferry surveys) conducted a visual survey effort from research vessels, naval service vessels and commercial ro-ro ferries between 2005 and 2011. Survey effort was conducted either from the ship’s bridge, the monkey island (the roof of the bridge) or from the crow’s nest (R.V. Celtic Explorer). Using an angle board and distances were estimated with the aid of a range-finding stick (Heinemann 1981). Environment data were recorded every 15 / 20 minutes using Logger 2000 software (IFAW 2000). Sightings were also recorded using Logger 2000. Automated position data were obtained through a laptop computer linked to a USB GPS receiver. Survey effort was conducted up to Beaufort sea-state six and in moderate to good visibility. As these were surveys onboard vessels of opportunity, the surveys were conducted in passing mode and cetaceans sighted were not approached. Sightings were identified to species level where possible, with species identifications being graded as definite, probable or possible. Where species identification could not be confirmed, sightings were downgraded (e.g. unidentified dolphin / unidentified whale / unidentified beaked whale etc.) according to criteria established for the IWDG’s cetacean sightings database (IWDG 2013). Observer effort focused on a 90-degree arc ahead of the ship; however, sightings located up to 90 degrees to port and starboard were included. Surveyors scanned the area by eye and using binoculars (typically 10X40 or 8X50). Bearings to sightings were measured.