Friday, April 12, 2013
Surfs Up for Burrunan Dolphins!
Today, a break from our usual Astronomy fare with a great video that is still somewhat related to science. Having a short breather for our hard working students, we found ourselves on a deserted beach watching one of natures most exhilarating spectacles - Dolphins surfing! The Pod of common bottlenose dolphins look positively pedestrian compared to the pod of Burrunan Dolphins (Tursiops Australis) that crashed the party and livened things up - A LOT! Burrunan Dolphins were only identified as a separate species by Dr Kate Charlton-Robb as recently as 2011. They are found only in Port Phillip Bay and the Gippsland Lakes and are very rare with a known population of only 150, and only 50 of those in the Gippsland Lakes area. Little did we know whilst watching the free show, that these were very special dolphins. On one very spectacular breach, I caught the sight of the white sides and tummy, thinking at the time that maybe there was a small Orca/Killer Whale out the back of the pack - I took a closer look at the footage when I got home, and thought - Hmmm I haven't seen any "black and white" dolphins before. So I started having a look around to see how many species of dolphins there were in Victoria, and found that this sounded like the new species that had been identified recently. I took a couple of freeze frames off the video and sent them to Dr Kate and voila - some very special video footage indeed. Burrunan Dolphins have a white side and underneath that comes up over the eye. In the video you can clearly see a number of them upside down under the wave crest, flashing their white tummies in the water like torpedoes. They are also known for their spectacular aerials which is clearly evident in the video. We watched them for over 30 minutes, taking 10-20 mins to fish followed by catching a couple of waves then moving out to the fishing grounds again. We observed 2-3 full cycles of this behavior. It was a stunning day, on the outgoing tide in mild conditions. So it was very far cry from "So long and thanks for all the fish" - these dolphins were having a ball and weren't going anywhere.