A TWO-YEAR SURVEY into Ireland’s marine life, which recorded sightings of a leatherback turtle and beluga whale, has improved the level of understanding of ecosystems in Irish waters, according to researchers. 

Over the course of two years the obSERVE Programme, a government initiative, collected data through two projects to improve our understanding of Atlantic ecosystems. 

The two projects, an aerial observation led by University College Cork and an underwater acoustic project led by Galway-Mayo IT, detected deep-diving species rarely seen above the ocean surface. 

2,200 sightings of whales, dolphins and porpoises were mapped and recorded, 20 species in total. 

Surveying large areas of the Atlantic Margin, Celtic and Irish seas, the study has provided insights into the relative abundance of fin, blue, sperm and long-finned pilot whales as well as dolphins. 

Up to 115-200km away from the west coast, endangered blue whales were detected underwater and strong seasonal patterns in their sounds were noted.

Using acoustic detection and tracking methods, 380 sperm whales, three species of beaked whales and are rare extralimital sightings of beluga (white whale) were recorded.

Welcoming the findings, Minister for Community Development and Natural Resources, Sean Canney said the findings show how important it is that government keeps investing in research into Ireland’s marine environment.

“The information gathered by the ObSERVE Programme has significantly improved our knowledge of the environment, offshore Ireland, and will help to point the way forward for future regulation and sustainable development in tandem with advancing the conservation of protected species,” Canney said in a statement.  

Minke whales were the most frequently observed and abundant baleen whale species – approximately 12,000 in summer and 5,000 in winter.

During the summer period, blue sharks and basking sharks were predominantly observed. 

For dolphin species, there was a considerable variation in their distribution, abundance and movements.

Densities of short-beaked common dolphins and common bottlenose dolphins were much higher during the winter than the summer, whereas harbour porpoises and minke whales were more commonly sighted in summer.

There were 9,433 sightings of an estimated 23,051 seabirds comprising 24
seabird species or species groups, including white-tailed tropicbirds, a species usually seen in the tropics.

Only a small number of turtles were sighted over the two years, with all sightings occurring in the summer for the leatherback turtle while there were summer and winter sightings of an unidentified turtle species.

Dr Mark Jessopp of UCC and part of the ObSERVE aerial team said the programme was particularly ambitious and logistically challenging but has “provided essential information”. 

“In addition, it has provided essential information on seabirds during both the summer breeding and overwintering periods. This is the first time we have been able to get robust estimates of cetacean abundance in winter and seabird abundance at sea essential to inform management and conservation of populations”.