Dave Riggs is searching for a dead blue whale.
The Esperance-based filmmaker usually prefers his subjects alive with black and white markings and swimming in pods through the Bremer Canyon.
For almost two decades he's pursued killer whales off Western Australia's south coast, creating documentaries and videos that have aired all over the world.
One day on the job, he witnessed a brutal attack.
A lone blue whale was hunted and skinned alive by about 70 killer whales.
Its death was long and drawn out and, according to Riggs, stomach-churning to watch.
But as the enormous mammal's body eventually sunk into the ocean and out of sight, he noticed a large oil slick remained on the water's surface.
It stayed there for months, clearly marking the place where the whale was killed.
'Your chances of finding one are pretty slim'
The death of a whale is a huge event.
Those that fall through the water column, rather than bloat with gas and float to shore, provide an extraordinary feast for all sorts of creatures.
Whale carcasses in the deep ocean, known to the scientific community as "whale falls", are home to some of the most extreme forms of life on earth, like chemosynthetic bacteria, which does not need light to survive.
Some of these organisms are found exclusively in whale falls and somehow migrate from one carcass to the next, while others are only also found in similarly harsh environments like hydrothermal vents and cold seeps.
In 2020, the Schmidt Ocean Institute took a research vessel to the Bremer Canyon and, using a deep-sea remotely operated vehicle, found a dead whale more than 1,500 metres below the surface.
In a video on the organisation's website, palaeoecologist Marco Taviani is clearly excited.
"It is obviously one of the best days of my life, scientifically speaking," he says.
Another scientist on the video, Andrew Hosie, points out how rare it is to find a whale fall.
He says most research involves towing a whale that has died during a beach stranding out to sea, weighing it down and then studying then it after a few years.
Marine biologist Pia Markovic, who works for Bremer Bay tour company Naturaliste Charters, says despite their ecological significance whale falls are understudied.
But Riggs thinks he may have a better chance than most.
'Stranger things have happened'
Right about now, blue whales are making their way along Australia's south coast, on their way to the warmer waters of Indonesia.
But the route takes them through the bottleneck of the Bremer Canyon, where pods of killer whales are lying in wait.
Riggs will also be waiting this year, using drones to search the water's surface for an oil slick, the tell-tale sign of a recent kill.
Only once he's found one will he be able to put his plan into action to attach live-streaming cameras to the corpse as it begins its journey to the ocean's depths.
He is sure it won't be easy.
Although whale falls are sampled occasionally by research vessels, as the Schmidt Ocean Institute did at Bremer in 2020, Riggs believes it's unique to have cameras on a fresh corpse, particularly if it was still making its way to its final resting place.
The years spent filming in the Bremer region has given him insight into the smorgasbord of creatures the body may attract, like the giant squid with a six-metre mantle he filmed two years ago.
Ms Markovic says if he could pull it off, scientists would be fascinated.
"Even if you could just get a camera on it for one minute, what you'd be able to see would be incredible," she says.
"It'd be awesome for science and awesome for us to see what's down there."
But Riggs's motivations seem to lie more with the sense of wonder that comes from exploring the ocean and its inhabitants, and a desire to share that feeling with more people.
"I can imagine it's a little disheartening for particularly younger people to think everything's been done.
"But there's so much left to be discovered, even in your own backyard."
