a dolphin doing ‘yoga’


Names): Australian snubfin dolphin (Orcaella heinsohni)

Band: Marine mammals

Cut: Length 2-2.5 meters, weight up to 130 kg

Diet: Carnivorous, eating fish and cephalopods (squid)

Habitat/range: Australia’s northern tropical coastal waters including WA, NT and QLD

Conservation state: Listed as vulnerable in Queensland

Superpower: Snubfin dolphins have vertebrae that allow them to flex their necks, unlike most other dolphins and whales. Because of this, they can surface and breathe without showing their dorsal fin – very sneaky! That means scientists have to be patient when trying to photograph their dorsal fins to identify individuals and track them over time.

Snubfin dolphins have a distinctive rounded head and no beak. Credit: Holly Raudino.

The snubfin dolphin lives in the tropical waters of northern Australia and was only recently recognized as a species, in 2005. It was previously thought to be the Irrawaddy dolphin, a close relative which lives in Asian waters. It is currently believed that there are fewer than 10,000 adults of the species. The densest population, consisting of about 100 individuals, inhabits the Yawuru Sea Country in Roebuck Bay, Broome, Western Australia.

These dolphins have a distinctive appearance, with a round, blunt head and no beak, which makes them distinctive from more familiar dolphin species. The snubfin dolphin has a small circular fin on its back, and they often bear marks on these fins from interactions with other dolphins, sharks trying to eat them, entanglement in fishing gear, and be hit by boats. The marks are handy for scientists, who use them as natural beacons to distinguish individuals and track dolphins over time through repeated photography and sightings.

Photograph of the ocean with the heads and dorsal fins of two snubfin dolphins visible
Two snubfin dolphins surface. Credit: Holly Raudino.

The favorite food of snubfin dolphins is fish of various sizes, from large salmon to small baitfish, and they are often found feeding in the mouths of streams at high tide. They have been observed displaying a specialized tactic of ‘spit feeding’, where they shoot a jet of water up to two meters high in front of them, and appear to drive fish back towards their mouths to an easy snack.

These dolphins are brown in color, with a low surface profile – as such they are highly camouflaged in the shallow, muddy waters they prefer. They can be great fun to watch as they feed in shallow water. They perform yoga-like movements, such as standing their heads up with their tails out, while searching the seabed for fish hiding in the mud. Snubfins sometimes emerge from a food-covered head to dive into muddy clay. Scientists call this behavior “bottom grubbing”. A group of dolphins resting on the surface of the water, lined up like sausages on a barbecue, is referred to by the very Australian term “snagging”.

A baby snubfin dolphin coming to the surface of the ocean with its mother's back also visible
A mother and her little snubfin. Credit: Holly Raudino.

A bit shy around boats, snubfins prefer to swim in their mangrove habitat. They only have one calf at a time, and one calf stays with its mother suckling and swimming near its mother’s tail in “baby position”. After a few years, the calves are weaned and become independent.

This species is gregarious and can form large groups of 20-30 individuals with lots of close body contact when socializing. They can become very active, splashing on the surface of the water. To avoid amorous attention, you can see an inversion, where the dolphin presents a red-pink belly to avoid mating attempts.

Snubfins can sometimes be seen swimming with other dolphin species, such as bottlenose dolphins and humpback dolphins, socializing or feeding together. Sometimes these interactions seem friendly and can have mutual benefits; at other times, they seem hostile. There is genetic evidence that snubfins did indeed mate and hybridize with humpback dolphins.

This wonderful marine species is a worthy candidate for Australian Mammal of the Year!

We all love birds, but why should our feathered friends have fun? This winter, join Cosmos in celebrating the incredible diversity of Australian mammals, from the antechinus to the yellow-legged wallaby, in our first-ever Australian Mammal of the Year poll.

Keep an eye on the Cosmos website or subscribe to our mailing list for new awesome articles. Australian mammal species every week. You can even nominate your own favorite Australian mammal using the form below!


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