The Discovery channel affiliate "Animal Planet" scored serious ratings on TV/Cable for their compelling series on the species they call "mermaids". Judging by the video evidence I am inclined to believe that the species exist. On the other hand it's not just a scientific adventure. Like everything else today there is a political motivation to consider. US security with sonar defense and oil exploration using sonar technology is alleged to be killing whales and other marine mammals. There is a lot of money riding on the verdict and as usual the US government as well as international regimes are accused of stealing and hiding evidence. It's a tough one to call.