Last Sunday, 9th November, I had a call from local birder Dan Houghton, informing me of a cetacean corpse that had washed up on the beach at Hill Head. As luck would have it, Dylan Walker, a marine biologist and co-founder of Whalefest and the World Cetacean Alliance, was staying with me, so we headed down to Hill Head to check it out.
Cetacean Corpse, Hill Head - November 2014 |
The corpse was very badly decomposed and it was evident that it must have been floating around out at sea for a while. The beak was exposed and all the teeth were missing, and the rib cage and backbone were exposed. There was no evidence of fishing nets wrapped around it, and there was no obvious evidence of a propeller strike, but it was in very poor condition and difficult to make out anything. Given its condition it was clearly going to be tricky to get a positive ID as to species, but there were a few pointers to guide us.
Beak of Cetacean Corpse, Hill Head |
The corpse measured around 2 meters in length, which would tend to rule out Harbour Porpoise, since this species averages 1.5m in length, with the largest being 1.9m. It would probably also rule Bottle-nosed Dolphin as this species would be much larger, although of course it could be a juvenile. The beak was damaged but it was possible to count 30 tooth holes, again too many for Harbour Porpoise, which usually has between 22 - 28, but interestingly not enough for Short-beaked Common Dolphin which would have between 41 - 57 pairs of teeth, and what we considered to be our most likely candidate.
Exposed Ribs and Vertebrae |
There were no other clues for us to work with and we may never find out what the species was, but it was apparently being collected and therefore DNA analysis will undoubtedly hold the key to its identity. We were able to establish that it was a male, and this is evident in the image below.
Male Genitalia on Cetacean Corpse at Hill Head |
Harbour Porpoises and Common Dolphins have been recorded in The Solent and I posted previously about a Harbour Porpoise corpse which washed up at Hill Head in August 2012. There is of course no telling where this corpse has come from since it has obviously been floating around at sea for a while, so who knows what it will turn out to be.
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