Dolphins

Seven species of the dolphin family have been found in Icelandic waters. Species described separately are the killer whale, pilot whale, white-sided dolphin and white-beaked dolphin, all common in Icelandic waters. The three other species are quite rare. The striped dolphin (Stenella coeruleoalba) is one of the most abundant open ocean dolphins in the world. Icelandic waters are still too cold for this creature, as it is only known from a few sightings and strandings. The bottlenose dolphin (Tursiops truncatus) is the most popular dolphin species in aquaria as they are very adaptable and easily trained. It has been spotted a few times in whale surveys in southern Icelandic waters. The common dolphin (Delphinus delphis) is known from a few sightings and strandings.

White-beaked dolphin (Lagenorhynchus albirostris)

This is the most common dolphin around Iceland. It is found in abundance all around the country, both offshore and inshore, although they rarely venture very close to land. In Iceland this is therefore “the dolphin”. The numbers in Icelandic waters are thought to be a few tens of thousands, based on whale surveys. They can reach a size of up to 3 m in length and 350 kg. The feeding habits are diverse; the species is often associated with capelin and herring which it probably feeds on. Recent studies also indicate that codfishes are a common food source. Dolphin hunting has never been conducted in Icelandic waters on an industrial scale. However, they were hunted when the opportunity came. For example, when they were enclosed within drift ice or when they were sighted close to land within bays or fjords, they were herded ashore. They might also be harpooned from small rowing or sailing boats. There is no active hunting of dolphins these days, but they do sometimes drown in gillnets.

White-sided dolphin (Lagenorhynchus acutus)

This species is very similar to the white beaked dolphin but smaller and slimmer. It might actually be more common than the white-beaked dolphin in Icelandic waters, but its distribution pattern makes it a rare sight. As opposed to the white-beaked dolphin, this species is exclusively an open ocean animal and therefore almost never seen close to land. It also has a more southern distribution and is therefore mostly found in the warmer waters south of Iceland. A few hundred thousand animals are thought to be in the North Atlantic. Due to its distribution, white-sided dolphins have never been hunted in Icelandic waters, for the same reason they rarely drown in nets.

Killer whale (Orcinus orca)

The killer whale is the largest dolphin species in the world. It can reach up to 10 m in length and more than 6 t in weight. It also looks different from the classical dolphins as it is stockier and more robust. The killer whale is the most widely distributed animal in the world. This also applies to Icelandic waters as it can be seen all around the country. However, historically they have been most abundant off the east coast where they chase their most popular prey, the herring. Other marine mammals and fishes are also a prey for the killer whale.

Norwegian boats caught about 300 killer whales in Icelandic waters in the period from 1955 to 1972. However, killer whales have not been hunted actively by Icelanders, except that some were caught alive for aquariums. Quite many aquarium killer whales do indeed trace their origins to Iceland, the most famous being Keiko who starred in the movie Free Willie. A considerable effort was made by a US based fund to try to re-establish Keiko in the wild in Iceland. These attempts were unsuccessful and unfortunately Keiko died in the end from flu in Norway. The reason why Icelandic killer whales became popular in the aquarium trade is that Icelandic purse seine skippers invented ways to catch individuals alive without killing the rest of the pod, as was frequently done in other countries where killer whales were hunted for aquariums. The estimated number of killer whales in Icelandic waters is about 5,500.

Long- finned pilot whale (Globicephala melas)

This is a medium-sized toothed whale (pilot whales are rarely regarded as dolphins although they are members of the dolphin family), the average size of males, which are larger, is 5.5 m and 1.7 t. This is a very common whale in the N. Atlantic with an estimated population size of about 780,000 individuals in the Northeast Atlantic. Pilot whale hunting is regularly conducted in the Faroe Islands where pods are driven ashore and slaughtered. The annual catch has for centuries been from 800 to 2,000 animals, and there are no indicators that this affects the stock. Similar hunting is, however, very rare in Iceland.

The pilot whale can be found offshore all around Iceland where the species is most common in late summer. Mass stranding of pilot whales is not uncommon in Iceland. As with so many large toothed whales, squid is the main food of the pilot whale.

References and further information

References: (Víkingsson, 2004i), (Víkingsson, 2004j), (Víkingsson, 2004k), (Víkingsson, 2004l), (Víkingsson, 2004m), (Víkingsson & Ólafsdóttir, 2004).

For full citation and further information on the main species in general see this page

Hreiðar Þór Valtýsson, University of Akureyri