IWDG welcome humpback whale #100 to Irish waters

It doesn’t seem that long ago when humpback whale sightings in Irish waters were a rare occurrence….. they were something that happened to others and in hard to reach places. Then something special

#HBIRL01, the 1st addition to the Irish Humpback whale catalogue Sept. 1999, Kinsale Gas Fields. Video: Eoin O’Mahony

happened in West Cork in September 1999; we not only got a sighting report of three humpback whales off the Kinsale Gas Fields, but this event was captured on video and even better still, the analogue film was of sufficiently good quality that we could freeze that crucial moment when a humpback whale reveals the expanse of its tail fluke and in so doing, a moment of pure magic was transformed into raw data. (Image right)

This was an important moment for the IWDG, as it was the birth of the Irish Humpback Whale Photo ID Catalogue. It grew slowly at first. In fact during the first decade there were years when it never grew at all, as humpback sightings remained worryingly rare.  Year on year, sightings of humpbacks were outnumbered by fin whales by a ratio of about 10:1. I recall Dr. Emer Rogan, UCC, asking me If I’d compile any data we had on humpback whale distribution in Irish waters, and her saying she was in no real hurry for this and that any time in the coming weeks would be fine. My reply was that I could give her the information over the phone.….as what we knew about humpbacks at the time, could have been written on the back of a post card. By the close of the 2010’s, there were just 12 individuals on the catalogue. We were still a quiet backwater on the international humpback whale circuit, with our only international match from 2007, to the Netherlands (#HBIRL7), which although of great interest to us, hardly set the world scientific literature alight.

Then during the second decade, there was a change. Humpback whale sightings became more numerous and West Cork it seemed no longer had a monopoly on the Big Winged New Englander, as individuals starting showing up as far east as Hook Head and Curracloe in Co. Wexford. But there was always a sense that these were outliers, the real range expansion was further west off the Slea Head Peninsula, Co. Kerry.

#HBIRL100, Dingle Bay, Co. Kerry, 20/07/2020 © Nick Massett

During the second half of the decade it seemed fairly evenly split between the West Cork and West Kerry hotspots. That was until 2015 when something changed in the northeast Atlantic and in this year alone, we doubled the numbers of animals on the catalogue from 33 to 66, with most of these showing up in West Kerry and almost all of them being new animals, never previously documented in Irish waters. The international research community started paying more attention to what was happening in the Irish southwest, as although our numbers were still relatively low compared to the major league players like Iceland and Norway, we were producing a year on year increase in sightings and the discovery curve was and remains on an upward trajectory. The significance of what IWDG was recording was not so much the increase in numbers, but that they were coming from an area where previously few humpbacks had been recorded.

We started off 2020 with 97 individually recognisable humpback whales, and it was always likely to be a big year for the catalogue, even with Covid.  This came to pass this week, when on July 20th Nick Massett ventured out on his RIB in search of humpbacks and among a group of three animals he found in outer Dingle Bay, two were new to us, as neither their tail flukes nor dorsal fins matched any of the other 99 individuals; and so we are delighted

#HBIRL73, Boa Vista, Cabo Verde, 25/02/2020 © Adilson Santos

to add #HBIRL100 (and #101) to this resource. It’s an important milestone and gives us a little space to reflect on just how far we’ve come with this long term monitoring project. By the end of 1990’s we had just two humpbacks documented, this was thirteen by 2010, but to have reached 100 by 2020, although not quite exponential, it is remarkable and surely mirrors the global recovery of this most iconic species. Also this week, we received our third Irish match to the Cabo Verde breeding ground, as photographs of a whale taken off Boa Vista on Feb. 25th 2020, confirm this individual to be our #HBIRL73, whom we last photographed off the Blasket Islands on June 25th 2019.

More whales, more re-sightings, more international matches to high latitude feeding areas and it seems matches to a tropical breeding site finally coming on stream. It’s a great story and one IWDG look forward to sharing with you over the next 21 years. It seems humpback whales have an endless capacity to inspire both whale watchers and whale researchers alike.

By Pádraig Whooley, IWDG Sightings OfficerHumpback whale images from the Photo-id Catalogue