Little information is known regarding the Australian snubfin dolphin as observations of this species are rare.
Scientific research has pointed out that the Australian snubfin dolphin is closely related to the Irrawaddy dolphin.
In fact until recent years it was believed that the Australian snubfin dolphin was a different colored version of the Irrawaddy dolphin.
As their name suggest the Australian snubfin dolphin can be found swimming in the Northern Australian waters.
The Australian snubfin dolphin make up one of over 40 different species of dolphin.
Physical Characteristics and Appearance
These marine mammals are noted for their similar physical appearance to the Irrawaddy dolphin, however there are some characteristics that differ between the two species.
The Australian snubfin dolphin has a brownish to gray colored back that gets lighter along the sides and the under body is white unlike the Irrawaddy dolphin which is a deeper grayish skin tone.
These dolphins possess a rounded head that’s blunt around the mouth area and lacks a beak and they have a pair of snubbed fins along the sides of their body, hence the name.
The dorsal fin is small, tapered back and located further down the back than other dolphin species.
They have a pair of round dark gray to black eyes and the blowhole is positioned on top of the head directly above the dolphins eyes.
In terms of their body length and weight the average size for the Australian snubfin dolphin is around 7 – 9 ft. long with females typically growing slightly larger than their male counterparts, and the average weight for these marine mammals is between 200 – 400 lbs.
Because the Australian snubfin dolphin is a marine mammal it is warm-blooded, breathes air, give birth to live young and produces milk to feed its babies.
Diet and Hunting Methods
The primarily diet of the Australian snubfin dolphin consists of various fish and cephalopods.
They have also been observed bottom feeding when searching for food.
As with other dolphin species these dolphins lecholocation can be used to navigate the ocean at night and search for potential prey.
Habitat and Migration
The Australian snubfin dolphin is found exclusively in Australia, primarily in Northern Australian waters.
Within Australia these dolphins inhibit waters off the northern coast minimizing their offshore range.
Social Structure and Communication
Not much is known about the social structure of these dolphins as observations are too rare to come to any conclusions, however they are believed to be a naturally rare species.
These dolphins have been observed traveling in pods of 6 or less dolphins, however rare encounters of 12 or more have also been observed.
Communication among the dolphin species consists of various high-pitched clicks and whistles that allow dolphins to communicate with one another, alert others of predators, search for a potential mating partner, inform their pod of food sources and to communicate a number of other important things to other pod members and local dolphins.
Breeding and Reproduction
The average gestation period for these dolphins is believed to be between 12 – 14 months.
Newborns are most likely fed milk and nursed until they are able to hunt and fend for themselves.
Sexual maturity begins between the ages of 4 and 8 years when these dolphins may begin mating and bearing offspring of their own.
From limited information that has been gathered it is assumed that the Australian snubfin dolphin has a lifespan of around 30 years.
The Australian snubfin dolphin is known to face a number of threats that are primairly humans based, however physical scarring suggests that they may also face occasional threats from sharks.
Belew is a list of the most common threats Australian snubfin dolphins are likely to face:
- Waste/chemical Pollution
- Boat strikes
- Habitat degradation
- Noise Pollution
- Direct kill
Over-fishing– The Australian snubfin dolphin may face threats from over-fishing which can cause these marine mammals to face issues with depleting food supplies due to human competition.
Lowered available food resources would require these marine mammals to either migrate away or potentially deal with increased competition for food resources.
Waste/chemical pollution – Waste and chemicals from commercialized areas and agricultural runoffs may interfere with the habitat of the Australian snubfin dolphin.
Increased pollution could lead to diminishing food stocks, disease and/or other health/reproductive complications.
Bycatch – In commercial fishing areas snubfin dolphins have been known to accidentally swim into fishing nets and shark nets while looking for food and as a result end up drowning due to their inability to resurface for air.
Because dolphins are marine mammals they cannot survive underwater for very long and must frequent the surface to taken in fresh air before holding their breath for another dive.
Boat strikes – Boat strikes are another potential cause of injury or death among the Australian snubfin dolphin.
As medium to large boats pass by they risk striking a dolphin as they travel.
This is likely more frequent in areas that are both highly commercialized and inhibited with larger numbers of snubfin dolphins.
Habitat degradation – The construction of marinas, recreational areas and resource extraction facilities/machinery can all create negative ecological impacts on the habitat of these marine mammals.
Noise pollution – Some researchers believe that noise pollution is becoming a growing concern in areas populated by marine mammals.
Noise pollution can interfere with echolocation and a marine mammals ability to identify natural sounds in the ocean.
It is even believed that loud man-made noises may create lesions and other forms of tissue damage to the brain and ears.
The more commercialized the area the more opportunities for noise pollution to occur.
Direct kill – While not well recorded these marine mammals may be purposely killed by hunters/poachers, however the cause for this is unknown.
Sharks – Lastly, the Australian snubfin dolphin may be attacked by sharks such as the bull shark and tiger shark.
The success of these attacks is unknown, however there has been scarring observed on the bodies of these marine mammals that have been made by predatory sharks which suggests that these attacks may occur from time to time.
Due to their rare status these dolphins have been given a high conservation priority status.