There were almost 39,400 sightings of 24 species of seabirds and almost 2,200 sightings of 17 species of cetaceans, according to the ObSERVE Phase II Aerial Project published this week.
The aerial surveys during summer 2021 and summer and winter 2022 recorded common species of seabirds such as northern gannets, black-legged kittiwakes, northern fulmars, and common guillemots.
Cetacean sightings included common dolphins, bottlenose dolphins, harbour porpoise and minke whales, as well as rarer sightings of species such as killer whales and beaked whales.
Other species sighted included sunfish, basking sharks, and blue sharks, according to the report published by the Minister of State with responsibility for Communications and Circular Economy Ossian Smyth.
ObSERVE is overseen by the Department of the Environment in partnership with the Department of Housing, Local Government and Heritage and the Sustainable Energy Authority of Ireland (SEAI) as part of the Government’s role in the sustainable management of offshore activities and appropriate marine conservation strategies.
The contract for this aerial project was awarded to University College Cork (UCC), which carried out a series of broad scale and fine scale aerial surveys of Irish offshore areas.
Guillemots, puffins, razorbills petrels, gannets and Manx shearwaters were primarily recorded in summer, while fulmars and black-legged kittiwakes were seen in greater numbers in winter, the report says.
The entire area was estimated to support over 1.5 million seabirds in both summer and winter, with the broad scale surveys highlighting “hotspots” in the Irish Sea and coastal waters off the southwest and west coasts for seabirds.
Fine scale surveys further highlighted the importance of the southwest coastal waters for seabirds, with an estimated 200,000 seabirds in summer, 320,000 seabirds in autumn and 40,000 seabirds in winter.
Avian flu is estimated to have caused mortality of up to 3,000 northern gannets.
At least three species of the deep diving, and poorly known beaked whales were recorded, with an estimated 2,000 individuals in summer and 3,700 in winter, primarily concentrated along the continental shelf break along the west coast of Ireland.
Sightings of rarer species such as false killer whale also occurred, the report says.
Common dolphins were the most abundant cetacean species, showing higher abundances than in Phase I of the ObSERVE programme in 2015-2016. They were particularly abundant in 2021 (approximately 600,000 in summer and 250,000 in winter).
Bottlenose dolphins were the second most abundant cetacean in Irish waters, with around 35,000 individuals in summer and 24,000 in winter. The Celtic Sea and coastal areas of the west coast were highlighted as important for both dolphin species.
Harbour porpoise, the smallest cetacean in Irish waters, showed particularly low numbers in 2022 (7,500 individuals in summer and 6,600 individuals in winter) compared to Phase I of the ObSERVE programme, and primarily occurred in the Irish Sea.
Minke whale was the most frequently observed and most abundant of the baleen whales (between 2,000 and 4,600 in summer and 500 in winter). Minke whales were primarily recorded in coastal waters. The larger fin and humpback whales were also recorded.
Fin whales occurred in both summer and winter, highlighting the continental shelf edge as an important area for this species, possibly as a migratory corridor or for foraging.
“This information will help inform the way forward for future regulation and sustainable management of Ireland’s maritime area in tandem with advancing the conservation of protected species, and the identification of important areas for their natural ecology and its conservation,”Mr Smyth said.
The reports are available here
