'Cetaceans' around the Irish coast

The following 'Cetaceans' can be spotted around the Irish coast. The 'Bloody Bridge', near Newcastle, County Down is a particular hotspot, with Minke Whales, Fin Whales, Bottlenose Dolphins and Porpoises being not uncommon. A Humpback Whale also took up temporary residency in Strangford Lough for a few days last July.

Minke Whales

These can be seen of most headlands in the south and southwest of Ireland. Up to 10m long, there are estimated to be 500,000 to 1m worldwide. They are identified by their pointed snout, which breaks the water first, and their blow and dorsal fin can be seen at the same time, distinguishing them from other whales such as the fin whale. They often dive for five minutes between blows, reappearing in a completely different place, a behavioural pattern which has earned them the name“the slinky minke”.

Orcas - Killer Whales

These apex predators are often seen in matrilineal groups of two or three in sighting hotspots such as Cape Clear and the Blasket Islands. In March 2012 two were spotted in Newfoundland Bay beside Oysterhaven and in the summer of 2001 three took up residence in Cork Harbour. These highly intelligent hunters will eat almost anything, and fishermen in the Blasket Islands have known seals to jump into their boats in an attempt to escape the whales. Sonar monitoring of their activity suggests however that most 'Orcas' in Irish waters eat fish.

Fin Whales

The most commonly recorded large baleen whale in Irish waters, fin whales can grow up to 24m long and their blow, up to 6m high is visible from long distances on clear days. The second largest creature on earth, a close encounter is unforgettable a their powerful blow is followed by a long curve of their back, finally revealing their small dorsal fin before they slip below the water. They feed on fish, squid and copepods, attacking their prey at speed. Recent research suggests they may gulp 60 to 82 cubic meters, a volume of water equivalent to a school bus, doubling their size, before quickly squeezing it out through their baleen plates. Mature females produce a single calf every two to three years, and individuals can live to be ninety.

Humpback

Whales Relatively rare in Irish waters, the 11 - 16m humpback can be recognised by its broad head.

Bottlenose Dolphins

Larger than the common dolphins the bottlenose, up to 4m long will eat between 8 to 15kg of fish per day, mostly bottom dwelling fish but also eels, mullet, catfish, shark, rays and hermit crabs. They are quick to bow ride beside ships and will do so without jostling. They do not leap in the way the common dolphins will, but instead sometimes breach, clearing the water by 5m. They often school with other species, including pilot whales.

Harbour Porpoises

These are slow, often seen in pairs with their heads only just breaking the surface. They won’t take any interest in the boat, and be careful not to hit them. They feed mainly on shoals of Herring.