Dugong
Dugongs are related to elephants; they weigh up to 400kg and have hairy backs, so just how anyone could mistake one for a mermaid is beyond me. You would have had to have been out at sea for a very, very long time indeed.
Dugongs are mainly found in Australia’s tropical waters but occasionally one will venture down to Sydney for a visit. They’re almost impossible to photograph in the wild in Sydney, so we decided to cheat and photographed this one on a dive in Sydney Aquarium.