The Australian humpback dolphin (Sousa sahulensis) is a freshwater species found near the coast of tropical waters of Australia. A humpback dolphin has a lifespan for more than 40 years.
Approximately 10 - 12 years is when humpback dolphins reach sexual maturity. Every two to four years, the female gives birth to a calf.
Dolphins occur in small groups near estuaries, deep channels, rocky reefs, sheltered bays, open ocean, and occasionally in surf zones. Dolphins and other marine mammals are protected in Australian waters; however, their outlook remains uncertain.
Human pollution, habitat destruction, and climate change are the major threats facing dolphins in Australia. It is believed that many dolphin deaths during coastal winters are caused by ingestion of litter, boat strikes, and pollutants such as insecticides.
Other industries contribute to a significant number of dolphin deaths each year in other parts of the world, such as the tuna fishing, gill netting, and drift netting industries. It belongs to the same genus of Indo-pacific humpback dolphins (Sousa chinensis) and bottlenose dolphins.
Its status is Vulnerable in the IUCN Red List. Implications for conservation have already begun in the marine coastal areas.
If you enjoy reading about the Australian humpback dolphin, do check out interesting facts about the spinner dolphin and Amazon river dolphin.
Australian Humpback Dolphin Interesting Facts
What type of animal is an Australian humpback dolphin?
An Australian humpback dolphin (Sousa sahulensis) is a humpback dolphin species from the Delphinidae family.
What class of animal does the Australian humpback dolphin belong to?
The Australian humpback dolphin (Sousa sahulensis) is a dolphin that belongs to the Mammalia class of the Sousa genus. It comes under the same genus as the Bottlenose dolphin.
How many Australian humpback dolphins are there in the world?
In view of the low abundance estimates and the low population of mature individuals within their range that are commonly found, typically fewer than 150 individuals, it is unlikely that the humpback dolphin population will exceed 10,000 adults.
Where does the Australian humpback dolphin live?
The Australian humpback dolphin tends to cluster in small groups near estuaries, deep channels, rocky reefs, sheltered bays, open ocean, and occasionally in surf zones.
What is an Australian humpback dolphin habitat?
The Australian humpback dolphin lives near the coast of Australia and New Guinea in the tropical waters.
Who does the Australian humpback dolphin live with?
It lives in small groups.
How long does an Australian humpback dolphin live?
The life expectancy of a humpback dolphin exceeds 40 years. Humpback dolphins are thought to reach sexual maturity between the ages of 10 - 12 years. Each female gives birth to a single calf about every two to four years.
How do they reproduce?
The process of mating and calving takes place all year round. In an adult, gestation, and lactation last 10-12 months, and there is a 3-year calving interval.
Generally, the gestation period lasts 10-12 months. In the first couple of years of life, young calves are highly dependent on their mothers. Humpback dolphins are thought to reach maturity between the ages of 10 - 12 years.
Each female gives birth to a single calf about every two to four years. Approximately 30 years is the average length of life for an individual.
What is their conservation status?
The Australian humpback dolphin has been listed as Vulnerable in the IUCN red list. Dolphins and other marine mammals are protected in Australian marine waters.
However, their outlook remains uncertain. Environment issues, habitat loss, and climate change are the major threats facing dolphins in Australia. It is believed that many dolphin deaths during coastal winters are caused by ingestion of litter, boat strikes, and pollutants such as insecticides.
They are vulnerable to incidental captures in gill nets and shark nets set for bather protection. Their population status is around 150 individuals, and it doesn't seem like that the population will increase any further.
Australian Humpback Dolphin Fun Facts
What does the Australian humpback dolphin look like?
In terms of overall length, the number of teeth, and distribution, the Australian humpback dolphin is slightly different from the other three species.
Like its closest relative, the Chinese white dolphin has a distinctly white (often with a pink tinge) dorsal fin, while the Indo Pacific humpback (Sousa chinensis) from the Atlantic and the Indian Ocean have a lower dorsal fin and are more wide-based. A dark dorsal projection resembling a cape is another characteristic of the Australian humpback dolphin.
A humpback dolphin can grow to be as large as three and a half feet (one and a half meters).
Its dorsal fin is short and triangular, lacking the characteristic Hump of Indo Pacific humpback dolphins (Sousa chinensis) in the Atlantic and Indian oceans.
Gray is the dominant color of the body, with a light gray shading on the flanks.
The dark back is separated from the lighter belly by a diagonal capeline that extends from just above the eye and neck to the urogenital area. There is a tendency for adult animals to have white scarring and flecking on the head, the back, the dorsal fin, and the tailstock.
It is typically between the range of 88-110 lb (40-50 kg) at birth and between 507-550 lb (230-250 kg) in adulthood.
How cute are they?
The Australian humpback dolphin is a big-sized mammal with hairless and scaly skin. The snout of the dolphin is long and thin. Their intelligence and cuteness make them a great combination. Dolphins are loved by everyone, and they enjoy playing.
How do they communicate?
Dolphin species produce a variety of sounds, such as echolocation or sonar clicks, whistles, and burst pulse sounds, such as squawks and squeaks. It is assumed that dolphins use whistles for communication, identification, and location.
This is done through clicking, which is used for navigation and feeding. Humpback dolphins have been observed to display mating courtship between Australian snubfin dolphins (Orcaella heinsohni).
How big is the Australian humpback dolphin?
The Australian humpback dolphin is 3.3-8.9 ft (1-2.7 m) in size. It is one time smaller than the Indo-Pacific Humpback Dolphins (Sousa chinensis). It comes under the same genus as the bottlenose dolphin.
How fast can an Australian humpback dolphin swim?
Australian Humpback dolphins move at a cruising speed of 4.6 mph (7.4 kph) and at a top speed of 12.6 mph (20.3 kph)
How much does an Australian humpback dolphin weigh?
The Australian humpback dolphin weighs almost 507.1-551.1 lb (230-250 kg).
What are the male and female names of the species?
There is no separate name for the different sexes of Australian humpback dolphins. They are simply referred to as the male Australian humpback dolphin and the female humpback dolphin.
What would you call a baby Australian humpback dolphin?
A baby Australian humpback dolphin is called a calf.
What do they eat?
This dolphin species have been noted to be opportunistic, generalist feeders, eating many types of inshore and coastal waters reef fish. Various habitats like mangroves, sand beaches, seagrass meadows, and coral reefs inshore support feeding, with animals dispersed over wide areas or clustered together targeting local food sources.
In order to catch their prey, these marine mammals sometimes beach themselves and chase fish into shallow waters.
Are they dangerous?
No, this dolphin species are not dangerous at all.
Would they make a good pet?
Australian humpback dolphins are such lovable and intelligent creatures. They are friendly and adorable. It is not common to keep river dolphins as pets because they prefer living in freshwater.
Did you know...
According to their life history, for 17 years, dolphins in site fidelity were studied by scientists before they concluded that Sousa sahulensis was a new species from Australia.
For the most part, the classification of the organism was based on its DNA. Its mitochondrial DNA bases were found to have seven unique bases and its nuclear DNA base to be unique, supporting its label as a new species.
The genetic analyses of this species revealed seven unique mitochondrial DNA bases and one unique nuclear DNA base, supporting its status as a new species.
Taxonomic revision of the humpback dolphins (Sousa spp) and description was given by Jefferson in marine mammal science. According to the description of a new dolphin, it represents a separate species of dolphin known as the Australian humpback dolphin, which inhabits the marine waters of the Sahul Shelf from northern Australia to southern New Guinea.
An Indo-Pacific humpback dolphin (Sousa chinensis) species is distinguished from it by a wide distributional gap along Wallace's Line, a dorsal cape, and a lower dorsal fin.
How many Australian humpback dolphins are there?
A low density of mature humpback dolphins, typically less than 150 individuals within their range, and low abundance estimates make it unlikely that their numbers will surpass 10,000 adults.
Is the Australian humpback dolphin endangered?
There is no certainty about the future of marine mammals like common dolphins in Australian waters. Human pollution, habitat degradation, and climate change pose the greatest threats to dolphins in Australia.
Litter, boat strikes, and pollutants like insecticides have been blamed for many dolphin deaths in coastal waters. A number of industries, including tuna fishing, gill netting, and drift netting, in addition to dolphin fisheries, contribute to a large number of dolphin deaths each year.
Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! For more relatable content, check out these southern right whale dolphin facts and pumpkinseed sunfish facts pages.
You can even occupy yourself at home by coloring in one of our free printable dolphin coloring pages.
Main image by Cbrookes81.
Second image by Fritz Geller-Grimm