Wed. 10th... A big day for Irish humpback whale research

11th Dec 2008 With a sense that the current run of large whale activity off West Cork can't last forever, it was decided to organise another research cruise with Colin Barnes on the MV Holly Jo. It was made clear by Eugene Mc Keown of Biospheric Enginering Ltd, that the focus of this charter was "acoustics" and not photo ID... Hmmm!

Biospheric Engineering Ltd is an Acoustic Consultancy, specialising in the impact assessment of environmental noise and vibration, based in Bearna, Co. Galway. They are testing an acoustic detection system for cetaceans which is being developed under the Sea Change strategy with the support of the Marine Institute and the Marine Research Sub-programme of the National Development Plan 2007-2013. Eugene has been woring closely with the IWDG all summer and is a member of the PReCAST Steering Committee, a joint IWDG/GMIT initiative.

Within minutes of leaving Reen Pier on a mirror calm morning, we cut the engine and deployed hydrophones, as Eugene eaves dropped and recorded a group of 7-8 harbour porpoises at the mouth of Castletownshend Harbour. This was our first encounter of the day and I was begining to wonder whether I'd have been better off staying in the office. While "hanging around" I was secretly wishing the porpoises would leave the area so we could get out to where there were much larger subjects for reseach.

Porpoises recorded, we head offshore a few miles and before long picked up the familiar fin whale blows, but while observing these we were joined by several groups of common dolphins. One of which (pic) is quite unusual as it is another "melanistic" variety, who don't exhibit the typical "hourglass" pattern. These have been observed occasionally in the area in recent months, and Dave Wall has also documented them offshore. You could be forgiven for thinking this one is a striped dolphin. Hybrid?

Our first humpback encounter of the day was of a solitary animal #HBIRL6 who was first photographed by the Irish Naval Service off Loop Hd, Co. Clare in Oct 2004. It was re-sighted off Mine Hd, Co. Waterford on 17th Oct 2008, and it's nice to see it paying West Cork a visit just before Christmas.

Our second of five humpback encounters was of a pair, both of which were recognisable as #HBIRL 8&9. In fact #8 was visible at a huge distance due to his antics and as we approached it was clear it was displaying the full humpack behavioural repertoire. For the next while we idled the engine from a distance and watched, and photographed the spectacle, and when enough images were secured to confirm their identity we cut the engine and Eugene commenced acoustic recording, again in still conditions and a quiet sea.

Some time later I heard a celebratory holler coming from the wheelhouse. Eugene on playing back the file was listening to the first recording of "singing" humpbacks in Irish waters. This is almost without precedent in any European waters. This is an important discovery as conventional wisdom is that only the male humpbacks sing, and only when in tropical breeding grounds, when they use these vocalisations to attact females. West Cork in mid December is beautiful, but could never be described as tropical. We should be in a position to confirm the gender of #HBIRL9 before too long, as it was biopsied on 26/11/08 by Dr. Simon Berrow of the IWDG.

So in one day we have dispelled the myth that humpbacks only sing in the tropics and may also be able to dispell another myth that only males do the singing, if it transpires that HBIRL9 is a girl. F

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