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MAMMAL NAMES | Fish With A Womb:

The Names of the Many and Unexpected Dolphin Species in Irish Seas

The word 'dolphin' may ultimately come from the Greek word delphys, meaning 'womb'

Last month we had a close look at Ireland’s leather-winged bats that stir into activity each day on the island once the blazing authority of the sun has ceded to the softer governance of the moon. And over the next few months we will be looking at another group of Ireland’s mammals that, on the surface, seem to share little in common with these tiny night-flyers – the whales.

These mighty animals are far, far larger than the bats, and have a wildly different form due to them occupying the island’s seas rather than its skies. And yet, both of these groups share a similar evolutionary condition, looking more like non-mammalian vertebrates who inhabit their domain than any mammal to whom they are more closely related; the bats resembling birds while the whales resemble fish. Also, to human eyes, these groups share a similar air of mystery, in the whales case due to them being bathed in water rather than darkness. Just like the bats, then, an exploration of the names that have been given to the whales in Irish waters can reveal a great deal about their true nature, and we can begin by looking at those of the many different species of what is surely one of Ireland’s most celebrated cetaceans, the dolphin.

Today, we are all aware that dolphins are mammals, but up until the eighteenth century they were classified as fish until the great scientist Carolus Linnaeus erected the class Mammalia in the tenth edition of his hugely influential work Systema Naturae, published in 1758, and placed dolphins and their relatives in this new category. However, since ancient times it has been observed that dolphins and other whales possess a number of features making them different from fish, and this is clearly seen in the name ‘dolphin’ itself.

Tracking the evolution of the term ‘dolphin’ through various languages back to its origins swiftly reveals its true meaning. Thus, the English word is derived from the Old French daulphin, which itself comes from the Medieval Latin dolfinus via the Latin delphinus, that ultimately stems from the Greek word for ‘dolphin’, delphis, which is related to the Greek word for ‘womb’, delphys. The word ‘dolphin’, then, may derive from the ancient observation that these sea-dwellers give birth to live young, and so can be taken to mean the ‘fish with a womb’.

Detail from a restored dolphin fresco in the Minoan palace of Knossos in Crete, dating to c. 1500 BC

The most common dolphin in Ireland’s seas is, unsurprisingly, called the common dolphin, and its Latin name, Delphinus delphis, seems to be just a combination of the Latin and Greek words for ‘dolphin’, reflecting that this species is, as Hayden and Harrington put it in their book Exploring Irish Mammals, the ‘quintessential dolphin’. Its recognition as such also seems to be reflected in the Irish name for this species which is simply the Irish word for ‘dolphin’, deilf. It is thought to be a common dolphin that is depicted on the coat of arms of the town of Dungarvan and that of Waterford City, both of which are found in Co. Waterford in the southeast of Ireland which has a long coastline brushed by the waters of the Celtic Sea.

However, it is in the Atlantic waters off Co. Kerry in Ireland’s southwest that you will find a member of the dolphin species that is undoubtedly the most familiar to Irish people – the bottlenose dolphin. The widely celebrated Fungie has entertained crowds in the waters of Dingle for years, and bottlenose dolphins are probably second only to the common dolphin in terms of abundance in Ireland’s waters, although they are noticeably different in form. For one thing, they are quite a bit larger, common dolphins ranging between around 2.1 and 2.4 metres long and about 75 to over 120 kilograms in weight, depending on whether they are male or female or where they live, while bottlenose dolphin males can weigh up to around 270 kilograms and measure around four metres in length.

As their name suggests, though, it is the form of the face that really distinguishes them from others of their kind, their short, stubby beak certainly making them look ‘bottle-nosed’ in profile. Their Irish name also derives from this feature, although deilf bolgshrónach does not mean ‘bottle-nosed dolphin’ but ‘belly-nosed dolphin’.

In both cases, though, the name could be said to be slightly inaccurate, as the reference to the ‘nose’ here is really a reference to the snout, the actual nose of dolphins, as with all whales, being the blowhole on the top of the head, formed as the nostrils slid farther and farther back from their snouts over the course of their evolution as they became ever more adapted to life in the sea. So, the scientific name, Tursiops truncatus, could be said to be the most accurate name in this regard, deriving from the Latin tursio, meaning ‘porpoise’, the Greek ops, meaning ‘face’, and the Latin truncatus, meaning ‘cut-off’.

Good close-up of a bottlenose dolphin showing that its name is well deserved

Dolphins are also represented by a number of other species in Irish waters, such as the striped dolphin, white-sided dolphin, white-beaked dolphin, and Risso’s dolphin. But there are even more dolphins cruising through the seas bordering Ireland, and it might be surprising to learn that forms such as the killer whale are also members of the dolphin family, Delphinidae.

The killer whale is a far more imposing creature than the bottlenose dolphin, measuring between six and eight metres in length and can be up to around 20 times heavier or more. The abilities and intelligence of this mighty dolphin have long been apparent, something bolstered by recent documentary footage of them hunting seals, packs acting in unison to create waves to knock them off ice floes, or repeatedly tossing them high into the air, the cumulative impacts with the sea’s surface thought to marmalise the seal’s bones to make them easier to eat. Their English name, ‘killer whale’, though, is thought to derive from attacks on far larger prey than seals, stemming from their habit of attacking even larger whales than themselves – a pod of killer whales even having been observed attacking an adult blue whale and meeting with success.

Their scientific name, Orcinus orca, also seems to refer to the deadly nature of these dolphins, with orcinus being the Latin for ‘demon-like’, and orcus meaning ‘the underworld’. The word ‘orc’ used by J.R.R. Tolkien in The Lord of the Rings for a supernatural race of snaggle-toothed demon-folk may also stem from orcus, while, according to the Oxford English Dictionary, before this usage ‘orc’ was used to refer to ‘any of various ferocious sea creatures’ before coming to refer to ‘a large cetacean, especially the killer whale’. Thus, this seems to be how Linnaeus came to refer the killer whale to the genus Orca in the tenth edition of Systema Naturae, a name which survives in the species name of the killer whale today as well as in its alternative English name, ‘orca’.

The killer whale's alternative name 'orca' may derive from the same root as that for the orcs in J.R.R. Tolkien's 'The Lord of the Rings'

With all this talk of death and demons, though, we could get a very skewed perception of Ireland’s dolphins, seeing the killer whales as ruthless, remorseless death-dealers and other forms like the bottlenose dolphins as friendly, engaging scamps content to just frolic in the sea. The reality, of course, is far more nuanced, and it has become increasingly clear over recent decades that aggressive behaviour is quite common among dolphin species and they are not as happy-clappy as we might like to think, while one of the things that makes the killer whales so effective at hunting is their highly-developed social nature.

The problems that can arise due to the capture of killer whales and removal from their families to perform in captivity for human entertainment in places like Seaworld were starkly laid bare in the acclaimed 2013 documentary film Blackfish. The title of this film comes from yet another name for the killer whale, but there is another dolphin in Ireland’s seas that is also highly social and does not have dolphin in its title that is sometimes referred to as the blackfish – the long-finned pilot whale.

This dolphin, which is about half the size of the killer whale, owes the ‘pilot whale’ part of its English name to its habit of group swimming, with the members apparently swimming in a kind of formation behind a leader, a testament to how social these cetaceans are. The Irish name, míol phíolótach, also simply means ‘pilot whale’. In turn, its scientific name, Globicephala melas, derives from the Latin globus, meaning ‘round’, and the Greek words kephalos melas, meaning ‘head’ and ‘black’, respectively.

The long-finned pilot whale, Globicephala melas, really does have a round black head

Yet another dolphin in Irish waters that does not include that term in its name and is also known as the blackfish is the false killer whale. Its scientific name is similar to its English name, the genus name Pseudorca being derived from the Greek pseudos, meaning ‘false’, and the Latin orcus, which, as we have already seen, refers to the underworld but also to the killer whale. Similarly, where the Irish name for the killer whale is cráin dubh, or ‘black sow’, the Irish name for the false killer whale is cráin dubh bréagach, or the ‘false black sow’.

It is easy to see why the false killer whale is sometimes referred to as the blackfish

So, Ireland’s dolphins are a far more diverse and complex group than many of us would once have thought, and though we might scoff at the ancients for regarding them as fish, many people in Ireland (including myself) could be accused of not knowing these fellow mammals half as well as they would like to think. Hopefully, this short account of the names of the dolphins in Irish seas may serve as just the first dip of the toe in an ocean of knowledge related to these marine marvels, whose richness as a group in Ireland’s waters extends well beyond names like ‘Fungie’ or the ‘fish with a womb’.

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