At present there are two recognized species of bottlenose dolphin, and in some cases, both species can be found in the same area. The two species are the common bottlenose dolphin (Tursiops truncatus), and the Indo-Pacific bottlenose dolphin (T. aduncus). In addition, there is a great deal of variation in colouration, diet and behaviour. The difference between the common bottlenose and Indo-Pacific bottlenose dolphin are subtle, but the common bottlenose dolphin generally larger and more robust with a slight darker colouration.
Conservation status: Least Concern
Conservation status: It is difficult to assign a conservation status to either common or Indo-Pacific bottlenose dolphins on a global scale. Indo-Pacific bottlenose dolphins are particularly difficult to assess, because they tend to occur in fragmented coastal populations, and their range includes many countries where little or no formal research has taken place. Currently the Indo-Pacific bottlenose dolphins is listed as Data Deficient and common bottlenose dolphins are considered Least Concern by the IUCN.
Like other dolphins these are fast animals, so a camera with a good shutter speed will pay off with bottlenose dolphins.
Since they spend most of their time under the water, consider the lack of contrast compared to land or sky-based animals.
Frequently Asked Questions
Our whale spotter tells us about the world famous Bottlenose Dolphin.
Identification – Which bottlenose dolphins do you see?
Around Dyer Island, we can encounter the Indo-Pacific bottlenose dolphin which is a sub-species of the bottlenose dolphin. Their body colour is also lighter than that of the Common bottlenose dolphin. The dorsal fin is large and curved. They usually measure between 1.8 to 2.5m and weigh between 120 to 200 kg. They are usually found in coastal waters and are rarely found in waters deeper than 100m.
Diet – What do Bottlenose dolphins eat?
The Indo-Pacific bottlenose dolphins have a wide variety of prey but predominantly feed on eat fish and cephalopods (e.g. squid & octopus) that can be found in shallow waters, but they can also feed on pelagic and off-shore fish species.
Social – Do Bottlenose dolphins like to socialise?
Bottlenose dolphins live in groups from 5 to 60 individuals but can sometimes be seen in groups of 100 animals or more. The groups tend to be larger if there are calves present, but the groups are relatively fluid.
Births occur predominantly in months with higher water temperature but can happen all year round. Females have usually one calf every 3 to 6 years and wean for up to 3-5 years. The female is sexually mature between 12 to 15 years old, the male between 10 to 15 years. The gestation period (pregnancy) is one year. The calf measures approximately 0.8-1.2m long at birth weighs anywhere between 9-21kg and is born tail first.
Fun Fact: Using a technique similar to sonar, sending ultrasounds through the water, which is then bounced back to the animal and used to navigate and detect potential food sources