Common members of the species The first aquatic mammals that whale watching visitors are likely to see in Hervey Bay are not whales, but dolphins. The famous humpback whales are often accompanied on their journey south by bottle-nosed and common varieties, and there is a local population as well. Dolphins are members of a group of mammals called cetaceans. Whales are usually much larger, whereas porpoises are smaller.
Many dolphins are playful and social, sometimes swimming with humans.
Porpoises, on the other hand, are usually more solitary and keep a lower profile. Its short beak and large teeth makes it look as if it is always smiling. Bottle-nosed dolphins are usually very friendly to humans, who can swim with them and pat them in several places around Australia. They are mostly grey in colour, with their backs being darker than their bellies. These creatures live in temperate to tropical waters mostly within 160 kilometers of land and often in bays and protected areas, where the water is quite shallow, such as at Hervey Bay .