Humpback whale off Southern Sri Lanka. Photo credit Tony Wu.
Location of the Arabian Sea
At the moment I am attending an Arabian Sea Humpback Whale meeting in Dubai. It’s nice to have so many like-minded people from our region in one space. So far, I’ve learnt a lot. Based on recent genetic analyses the ASHWs as they are called are potentially the most isolated baleen whale population in the world. They are also potentially the only non-migratory humpback whale population in the world. At the moment there are about 86 individuals in the population that seem to hang out only in the Arabian Sea. The IUCN Red List categorises them as Endangered and there has been a lot of interesting debate about whether they should be upgraded to ‘Critically Endangered’ status on the basis that they are possibly the only population of humpback whales that are not making a dramatic recovery. That’s a tricky one because they have only ever been comprehensively studied around Oman and they may well stray to other parts that we are yet to survey.
I’ve definitely learnt a lot about these whales in the one day I have been here. Here’s a few quick facts:
1. The song of the ASHWs was first recorded by Hal Whitehead in Sri Lankan waters in 1982.
2. The first photo of a live ASHW was taken in 1985 by M. Gallagher. This is therefore the first individual in the ASHW photo ID database.
3. Soviet whaling data supports the theory of a resident Arabian Sea population (for example none of the ASHWs they caught had cookie-cutter scarring which is apparently associated with migration across the equator.
4. We are still trying to figure out the limits of the range of these animals – perhaps their core area of occupancy is in the Arabian Sea but maybe some of them venture beyond?
Essentially, the picture is a bit more complicated than we think as with ALL marine mammals.
In fact, on the 21 of February 2014 underwater photographer Tony Wu took this photograph of a humpback whale (potentially a juvenile) off the southern coast of Sri Lanka. A rare sighting given that we only have a handful of verified sightings from our waters and a couple of strandings. No sooner had he taken the image, he emailed it to me asking what I thought. Knowing that the Environmental Society of Oman maintained the comprehensive photo ID catalogue for this population, I immediately touched base with my friends out there in the hopes of finding a match. What does that mean? Well we wanted to see if this whale, photographed by Tony, had been photographed in the Arabian Sea. If it had, then we would know the origins of this rare sighting. Thanks to the expertise of Dr. Gianna Minton who has worked with this population since 1995 and knows the population inside out, we soon had an answer. The match was negative. Turns out, this guy didn’t match with any in her catalogue, indicating that (potentially), this whale had come from elsewhere and NOT the Arabian Sea. As with all cetacean stories, this one too remains unsolved….
To read Tony’s blog piece about this please head to http://www.tonywublog.com/journal/first-ever-record-of-humpback-whale-in-sri-lanka