Mystery as rare sunfish wash up at Aussie beaches: 'Never seen anything like it'

Locals were stunned by the sunfish discovery, but how rare is it?

Curious beachgoers have flocked around the bodies of two elusive sunfish mysteriously found dead within days of each other on a 70km stretch of Australia’s coastline.

NSW woman Judith Merchant told Yahoo News she rushed to a beach south of Wollongong after hearing about the giant disc-shaped creatures, and seeing them up close left her “in awe” but also “sad”.

“It seems a macabre thing to photograph, but I was really blown away. I thought I’ll never see another one, so I took advantage of the situation to have a look at something phenomenal up close,” she said.

Left - the Warilla Beach sunfish with a man standing near it. Right - a thong next to the sunfish's flipper.
Dozens of onlookers took photos of a sunfish at Warilla Beach. Source: Darren Steain/Judith Merchant

Have you seen a sunfish wash up? Send your pictures to michael.dahlstrom@yahooinc.com

In a video supplied to Yahoo, Judith puts her white thong next to the fish to illustrate it's size. "It's ginormous," she says of the fish she later estimated to be more than 2 metres long. You can watch the video below.

The two isolated strandings were linked together by local man Darren Malone who runs a community social media page. Locals reported the first sunfish at Sussex Inlet on November 12, then three days later others sent him photos of another one which was seen at Warilla Beach. “In all the years I’ve lived here I’ve never seen one,” he said. “People have been here for 35 years have never seen anything like it.”

Hunt for sunfish expert to explain double stranding

While the sunfish have got locals excited, we wanted to understand just how rare the sunfish really are.

While there are five seperate species, finding people with expertise in sunfish is rare, as there are few funds available to study them.

A contact in the United States was able to connect Yahoo to a Danish marine biologist Dr Marianne Nyegaard who was travelling on a ship to Antarctica.

Despite the patchy internet service onboard, we were able to communicate via text message and she helped analyse the images.

Nyegaard, who has expertise in Southern Hemisphere sunfish, described the double stranding as "rare" but not "very rare". Put simply, she couldn’t recall another in Australia, but they have occurred in New Zealand — three once washed up there.

What killed the sunfish?

While several photos were taken of NSW sunfish, Nyegaard said it is almost impossible to determine what killed them. “Stranded sunfish typically appear to have been healthy with no obvious cause of death, or impairment to explain why they ended up on the beach,” she said.

When looking at strandings in general, she believes it's possible they sometimes "fall onto land" in the same way humans "fall into the ocean". However the science on this is not settled.

Judith poses next to the Warilla Beach sunfish  - left. And the Sussex Inlet sunfish in the sand - right.
Judith poses next to the Warilla Beach sunfish (left) which was found days after one was photographed dead at Sussex Inlet. Source: Judith Merchant

Are sunfish rare to see in Australian oceans?

While sunfish are seldom seen in the wild in eastern Australia, the stretch of NSW coastline where they were found is known sunfish habitat.

Reports of sunfish elsewhere are more common, with Nyegaard explaining sightings frequently occurring from tourists and fishermen visiting the south coast of Western Australia, Bali, Galápagos Islands, New Zealand and California.

“It is very much a matter of going to the places where sunfish live — this is not something the average person has an opportunity to do very often,” she said.

One of the biggest threats sunfish face globally is being caught as bycatch by commercial fishermen angling for other species. Another potential threat is climate change, as rising temperatures, decreased oxygen levels and changing ocean currents are all likely to impact them.

The NSW Department of Primary Industries directed Yahoo's questions about the sightings to the Australian Museum. It has been contacted for comment.

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