Watch: Curious dolphins play with a right whale in Australia

Each year, southern right whales travel more than 1,000 miles from the chilly waters of the Antarctic to warm nursery grounds along the Australian coast. The filter-feeding giants have just begun arriving on the south coast of the country – and one of them recently stopped en route for a bit of fun.

The beautifully filmed encounter appears to be an example of interspecies play. In many cases, animal interactions that initially look friendly turn out to be quite the opposite (just ask this baby impala), but this one does seem to check out, according to local experts.

"It appears to be play for both species," says Curt Jenner, director of the Centre for Whale Research Western Australia. "The dolphins are rolling with their bellies towards the whale which shows play, not aggression, and the whale is simply doing its best to keep up with the more agile dolphins."

Jenner notes that when right whales are agitated, they tend to beat their flukes on the surface of the water. "This does not appear to be the case here," he says. "It is just trying to follow them in its own clumsy way."

The footage was captured in South Australia's West Beach, which lies about five miles from Adelaide. According to aerial filmmaker Jaimen Hudson, who filmed the encounter, this isn't the first time such behaviour has been spotted in the area.

"My family have operated Esperance Island Cruises since before I was born, so I have been lucky enough to experience scenes like this," he says. "It certainly isn't something you come across all the time, and it is the first time that I have been lucky enough to capture it on film."

Dolphins are known to interact with their bigger and distant kin in other ways, too. Back in 2015, a mother-and-calf pair was filmed surfing the pressure wave created by a humpback whale in Australia. In neighbouring New Zealand, bottlenose dolphins occasionally pair up with false killer whales, sometimes for years on end.

To our knowledge, however, there haven't been any documented cases of longterm association between dolphins and a baleen whale like the southern right in Hudson's video. So it's likely that these cetacean cousins eventually swam their separate ways.

Drone photographer Jaimen Hudson

Hudson had been following the right whale for about an hour as it lumbered parallel to the shoreline. He was about to pack up for the day when the pod joined the party. "The dolphins appeared to have been just swimming along when they came across the whale and began interacting with it," he says. "It was a really cool experience."

Pointing out the patchy coloration of its skin, some online commenters expressed concern that the right whale may have been diseased. But those blotches (called "callosities") are perfectly normal for the species – and their white appearance is due to thousands of whale lice, tiny crustaceans that feed on dead skin and keep wounds clean in exchange for a floating "home".

Almost every species of whale has its own unique whale louse. Grey whales, for example, host orange freeloaders; the garden variety for right whales – Cyamus ovalus – is a pale, pinkish-white. Barnacles and other invertebrates also settle on these areas, adding to their rough texture (if you're not squeamish, check out a callosity close-up here).

An estimated 2,000 southern right whales cruise past Australia each year, typically between May and October – but only a small number use its shallows to give birth. The species is listed as locally endangered under the Australian Environmental Protection and Biodiversity Conservation Act, so each sighting of a healthy whale is an encouraging sign of recovery.

For Hudson, being able to share his love for marine life is particularly significant following his inspiring recovery from a life-changing motorcycle accident in 2008. Drone photography and videography has allowed his connection to the ocean to remain strong.

"Aerial filmmaking and photography has completely changed things for me since my accident," he says. "I have been passionate about the ocean and wildlife since a young age and found it difficult to access due to the fact I was in a wheelchair. I am stoked that people enjoy watching the videos as much as I enjoy capturing and creating them."