* Food availability: Bottlenose dolphins are opportunistic feeders, and their diet consists primarily of fish, squid, and crustaceans. These prey are abundant in both tropical and temperate waters, making these regions suitable for their survival.
* Water temperature: While they are found in warmer waters, bottlenose dolphins can adapt to a wide range of temperatures. Their blubber layer and ability to regulate their body temperature help them thrive in cooler waters as well.
* Geographic distribution: Bottlenose dolphins are found in all the world's oceans, with varying populations in different regions. They are more common in coastal areas, but can also be found in deeper waters.
However, it's true that some species of dolphins are more specifically adapted to tropical waters:
* Indo-Pacific bottlenose dolphins: These are found specifically in the Indo-Pacific region, with a strong preference for warmer waters.
* Atlantic spotted dolphins: While found in the Atlantic, they prefer warmer regions, and can be found in tropical zones.
Ultimately, bottlenose dolphins are highly adaptable and can thrive in a range of environments, making them one of the most widespread marine mammals on Earth.