On the evening of the 9 June 2025, the IWDG received a report of a large carcass floating off the coast of Galway. A few hours later the animal had stranded on Rusheen Bay, Co. Galway. The distinctive white “arm band” on its pectoral fin quickly identified it as a minke whale. The cause of death was tragically easy to deduce. Four deep gashes ran along its back from where a propellor had cut through skin, blubber, muscle and the spine on its dorsal. This showed the animal was alive when hit (as dead animal float with the ventral surface up) and the animal stood little chance of survival after being struck by a ship.
Minke whales are known to feed around the Irish coast from early spring months to well into the autumn. They are our smallest baleen whale species and are difficult to spot due to their size and elusive behaviour. This reduces the chances for mariners to take evasive action when a minke whale is in the area.
While anecdotal evidence of ship strikes in Ireland exists there are only a few records. The IWDG stranding scheme has identified three definite ship strikes; a common dolphin, a harbour porpoise and a bottlenose dolphin as well as two potential ship strikes, another porpoise and a sperm whale. Irish Ferries experienced serious delays in 2006 when the Jonathan Swift struck “a soft object” believed to be a whale. Alongside ships striking cetaceans, there are two confirmed records of ships striking basking sharks. In 2022 a ship sailed into Dublin Port with a fresh basking shark on its bow, likely struck in transit. Later in 2024, a tagged basking shark was struck by a large vessel off west Kerry, with the tag recording everything!
So, while we know that ship strikes are happening in Irish waters, accurately estimating the frequency of ship strikes is challenging. They are rarely reported often as the mariner is unaware that a strike has occurred, lack of information on where to report such an incident and maybe also due fear of public backlash. In addition to the low reporting rate, most large whale carcasses will sink rather than float and strand, further decreasing the likelihood of a ship strike being discovered.
Even still ship strikes have been identified as one of the biggest threats to large whales in our world’s oceans. Mitigation against ship strikes range from course changes and temporary shipping restrictions in high risk areas, to the movement of shipping channels to speed reductions. Ireland boasts of an incredible biodiverse ocean with 26 cetacean species known to occur in our waters. Identifying potential risks factors and implementing necessary mitigation factors is crucial to keep our oceans, and its inhabitant’s safe. Establishing a protocol for mariners to report negative interactions with cetaceans, such as ship strikes, entanglement and bycatch would greatly enhance our ability to make informed decisions.
The IWDG is a partner in two EU funded projects centred on preventing ship strikes by empowering mariners. For the OCEAN HORIZON project the IWDG has created a reporting app which allows mariners to report hazards, such as containers and whales, in the nearby area, alerting others so they too may avoid striking whales or lost shipping containers. Under the Atlantic Whale Deal the IWDG is testing the use of thermal cameras on large ships to enable early detection and thus avoidance. Alongside the creation of an early detection program, the IWDG partners in creating a European Atlantic Risk map which will help identify high risk areas for ship strikes to allow for informed decision making.
Emilie De Loose
Project Leader of the Atlantic Whale Deal
Previous IWDG article on ship strikes: https://iwdg.ie/concerning-ship-strikes-globally-and-in-the-shannon-estuary/
