The dusky dolphin is limited to the south of the planet including the tip of the American continent, New Zealand and some southern islands.
Bottlenose dolphins have a broad distribution that includes most of the tropical, subtropical and temperate parts of the ocean where there are several kinds of habitats.
Dolphins are not frequent victims of any predator in the ocean due to their sociability and intelligence, but killer whales and some large sharks are their main natural threat.
Dolphins evolved from land animals that returned to the ocean due to environment conditions.
The conservation status of up to 25% of the dolphin species is vulnerable or worst. Pollution, fishing, and hunting are factors that affect the development and survival of these cetaceans.