Irish Humpback whale match with Norway

7th Mar 2014

Between 10-13 May 2007 a humpback whale was photographed inshore, close to Texel Island in the Wadden Sea, Netherlands.  On 28 September 2007 a small humpback whale (5-6m in length) was photographed by Conor Ryan during a whale-watching trip off Toe Head, County Cork, Ireland. Images were compared with those in the IWDG Humpback Whale catalogue which showed it was previously unrecorded in Irish waters.

On 22 October 2007 Wouter-Jan Strietman, of the North Sea Foundation, having seen the images of the young humpback whale on the IWDG website www.iwdg.ie suggested that these two sightings were of the same animal. The match was confirmed by comparing images of barnacle scars on the whales left jaw. The match was also agreed by curators of the North Atlantic Humpback Whale catalogue at Allied Whale in the US who also noted that this whale was previously unrecorded from any other part of the North Atlantic.  This was the first match of a humpback whale within Northeast European continental shelf waters and the first ever, international match of a humpback whale from either Ireland or the Netherlands. 

HBIRL7, Ijmuiden, Netherlands 17/11/2007 © Wouter Jan StrietmanBetween 16-20 November 2007, seven weeks after the Irish sighting, the same humpback whale was re-sighted off the Ijmuiden area of the Netherlands, just 60km south of where it was initially recorded in May. During the six months (May-November) this juvenile humpback whale has completed at least a 2500km round trip within European waters.  The ecological significance of this record is difficult to determine.  The whale was small, estimated at 5-8m, probably a yearling or juvenile.  It was observed feeding, suggesting it was able to sustain itself. However, whether its movements are typical or aberrant are difficult to interpret.

A full account of this story appears in our Míol Mór, Issue 32, Spring 2008.

Update 9th February 2014

In November 2013 we first came across the name Fredrik Broms.  A plankton ecologist by profession, his curiosity was peaked when in late 2010 unprecedented numbers of humpback whales arrived in his local area, and he set up North Norwegian Humpback Whale Catalogue (NNHWC).  Since then, Fredrik has been very busy obtaining photo ID images of humpback whales in the high Arctic area of Tromso, in northern Norway Web: www.northernlightsphotography.no.  Critically, Fred has adopted a strong “citizen science” approach and is engaging with local whale watch operators and general public to secure humpback photo identification images. Humpback whale flukes poster  © NNHBWC

Fred writes… “The whole background of the catalogue is that all of a sudden lots of humpbacks were seen feeding on herring in North Norwegian waters in the winter, something that haven't been observed since the 1920's, so the same day as I heard about it (December 2010) I travelled to the area and started collecting ID-data and since then, the same pattern has repeated itself each winter.” 

Despite often extreme conditions with freezing temperatures and lack of day light at such latitudes, Fred has since collected a remarkable database of humpback fluke images, which currently stands at 214 identifications (Feb 2014), but could reach close on 300 recognisable individuals by the time he has analysed all of this seasons images. It’s therefore hardly surprising that with such high numbers, this Norwegian work is beginning to bear fruit and he has already made eight matches with the Cape Verdes and several matches with the Azores. As with IWDG, all images secured by his network are sent to the curators of the North Atlantic Humpback Whale Catalogue in Bar Harbour, Maine, USA.

So when we received an email from Fred in the middle of the night last weekend, we felt something must be up.  …..“I've been matching flukes like a maniac during the last week now and now at half past 1 in the morning (while entering new flukes I got from a friend) something in the back of my mind told me I had seen one of the 'old' flukes from somewhere, but I couldn't recall where. So I went looking in the Greenland catalogue, Dominican Republic, Cape Verdes, Northern Russia, Iceland and finally... Ireland.  Before cheering and dancing on the table I need your second opinion with this fluke shot, which I believe might actually be a match to HBIRL7 "Dutchy"

We didn’t need much convincing…the image taken off Kvaløya outside Tromsø, some 350 km inside the Arctic Circle on 17 Nov 2012 was both distant and grainy, but all parties are in agreement that it is indeed #HBIRL7. This is our most important match to date for a number of reasons.

 

HBIRL7, Tromso, Norway 17/11/2012, note 3 black scars on right fluke © Hjalmar WestgårdOn an emotional level, it’s great to know that this animal has survived the past 5 years.  Most observers agree that it was very small and Conor Ryan noted that it looked rather thin back in 2007, when it was likely to have carried out a round-trip through some of the planet’s busiest shipping lanes, crossing the Dover Straits. The risk of ship-strike to slow moving humpbacks can’t be overstated. Presumably 5 years later, #HBIRL7 can now be considered a more experienced adult, with an improved understanding of the “rules of the road”.

Scientifically, what relevance has the tracking of #HBIRL7 to a position some 2,100km north of its last known sighting?  Well, it highlights the need to be careful when referring to these humpbacks as “Irish”, as this latest sighting serves to remind us that they are not Irish, in the same way as they are neither Dutch nor Norwegian. So we only use the term “Irish humpbacks” loosely, as the one certainty is that they are not born here, so we can’t claim them.  They just happen to cross paths with us every now and then while passing through our waters, en route elsewhere. What remains a mystery is the origin of these “Irish humpbacks”, and there are only a few known options, i.e. the Cape Verde archipelago or the Caribbean; while we can’t rule out a third as of yet undiscovered North Atlantic breeding ground.Map of HBIRL7's likely route 2007-2012 © IWDG

IWDG has to date invested considerable energies into establishing where our humpbacks are born. And although we should be cautious in over-interpreting this one re-sight to an Arctic feeding ground, it is a significant development, in that it gives us another critical piece of the jig-saw.  If we use the analogy of a journey (migration) having a beginning, middle and an end, then based on its being confirmed off West Cork (Sept. 2007), the Netherlands (Nov. 2007) and Northern Norway (Nov. 2012), we may have the middle and end portion of the journey figured out.  This latest twist will encourage Irish and Norwegian teams to learn more about #HBIRL7, so we can jointly solve the riddle as to where it was born and where its journey began.

Establishing this fact isn’t a mere academic exercise, but is crucial for the conservation of the humpback whales visiting Irish waters each year in increasing numbers. We may be close to solving the mystery of this one humpback....just 27 others to go!

By Pádraig Whooley

IWDG Sightings Officer