Dugongs live in the tropical waters of the Indian and Pacific oceans. That means, we would never find them here in Europe.
Most of them are found in northern Australia waters between Shark Bay in Western Australia and Moreton Bay in Queensland.
Unfortunately, the animals are in danger in many parts of the world. But in Australia they are protected by law. So, you don't have to worry =)
Worldwide, there are only less than 40.000 dugongs left.