Fungie, Ireland's most famous dolphin, was a rare breed, study confirms

Fungie, the friendly dolphin that famously lived in the waters off of Dingle for nearly 30 years, was a mix of two genetically discrete populations of bottlenose dolphins, new research has found.

In Ireland, there are three genetically discrete populations of bottlenose dolphins: Shannon Estuary, Coastal, and Offshore. Fungie was a mix of Shannon Estuary and Offshore, according to research recently published in the journal “Ecology and Evolution."

The study, initiated in part by the Irish Whale and Dolphin Group (IWDG), sought to examine the genetics of bottlenose dolphins that had either been found dead along the shores or sampled while free-ranging at sea.

Some specific dolphins of interest were also sampled - those that were known as "solitary individuals" who tend to live alone rather than in pods and often seek out human contact.

Among these solitary individuals that were sampled were Nick, who stranded in Cork Harbour, Finn in Carlingford Lough, Dusty in North Clare, and Nimmo in Galway City.

However, the most famous of these solitary individuals is Fungie, the dolphin who was first spotted in Co Kerry's Dingle Bay in 1983 and became a mainstay in the area until he disappeared in October 2020.

Fungie. (RollingNews.ie)

Samples of bottlenose dolphin DNA were obtained using a number of sampling techniques - but how did researchers get a sample of DNA from Fungie since he disappeared nearly six years ago, just as the solitary sampling project began?

Co-author of the study Bogna Griffin explained to IWDG: “[Co-author] Seán O’Callaghan had been interested in Ireland’s unusually high number of solitary bottlenose dolphins, and we had been exploring non-invasive ways to determine which populations they belonged to."

During a research cruise on the IWDG's research vessel Celtic Mist, IWDG member Denis O’Regan said he had always worn the same wetsuit when swimming with Fungie and had not used it since their final swim together. He swabbed several areas of the wetsuit and sent it to Bogna.

“Denis kindly collected the swabs, I extracted and pooled the DNA and provided the samples, labelled blindly, to the study," Griffin said.

Subsequent laboratory analysis confirmed that the genetic data obtained from the samples collected was from dolphin DNA, not human, allowing further analysis and assignment of individuals to their respective source population.

Fungie. (RollingNews.ie)

To the authors' surprise, four of the five solitary dolphins were all from the Offshore population. Only Fungie was different – being of mixed ancestry between the Shannon and the Offshore populations.

According to IWDG, this is unusual because the research study showed that bottlenose dolphins in Ireland tend to be genetically identified as one specific population or another. It is thought that the Offshore population, which is genetically much more diverse than either the Shannon or Coastal populations, is the source population.

IWDG noted that following the last great melting of the ice 15-20,000 years ago, the sea level rose up to 200m, flooding coastal areas and providing new habitats for dolphins. Individuals from the Offshore population would have moved into these areas as new feeding opportunities occurred, and over time these dolphins would have become genetically discrete.

Fungie. (Getty Images)

Solitary dolphins in Ireland

Ireland has documented more “solitary” dolphins in recent years than nearly any other country, IWDG said this week. Most were bottlenose dolphins, of which Ireland hosts a large proportion of the European population. The implications for the management of these solitary dolphins are unclear.

“Why these dolphins seek human company rather than socialise with other bottlenose dolphins has long been a mystery,” said Dr. Simon Berrow of ATU and the IWDG, who initiated the study.

This new research on solitary dolphins, which is unique in the world, suggests solitary dolphins in Ireland are from a very different population to the dolphins they may encounter inshore.

“Maybe they do not understand each other and use different vocal dialects, confounding communication, or perhaps they just have very different ecologies,” Dr. Berrow suggested.

“What this study doesn’t explain is why they moved inshore in the first place, but maybe Ireland’s proximity to deep water and the offshore population facilitates this movement."

Seán O’Callaghan, co-author on the study and PhD candidate at ATU, said: “A lot of work has been done to record these unique solitary dolphins, but this study provides a new insight into some of these familiar dolphins using non-invasive sampling techniques and contributes significantly to the wider knowledge of solitary dolphins globally and from where they may originate."

The dolphin study was carried out by the late Lorenzo de Bonis as part of his IMBRsea Master’s thesis at the Atlantic Technological University (ATU) in Co Galway. Tragically, de Bonis passed away in a rock-climbing accident while he was finalising this work for publication, but the research team completed the publication process in his memory and as a legacy to his work.

Dr. Luca Mirimin at ATU, who supervised de Bonis and co-led the work, said that publishing the work was not only "important to advance our knowledge of such iconic marine mammals in Irish waters," but also as a way to honor de Bonis' work and legacy.