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How Do You Preserve a Rare Three-Ton Shark?

Inside the Museum Victoria's efforts to preserve the corpse of a gigantic basking shark.

by Alan Weedon
Jul 20 2015, 4:00pm

Image by David Pail

Museum Victoria staff inspecting the rare basking shark at Portland, Australia. Photo by David Paul

Sitting in the depths of the Melbourne Museum lies a very large and extremely rare fish. Known as the basking shark, it's the second-largest fish in the world; specimens average over 12 meters in length and usually weigh several tons. It's so rare the species has only been spotted three times in the museum's 160-year history.

Late last month, one basking shark came into the hands of Museum Victoria after a fishing trawler accidentally caught one and donated it. While they're usually found in the North Pacific and Atlantic, this one was caught off the coast of Portland, Victoria—about four hours drive southwest of Melbourne.

Little is known about the sharks as they rarely—if ever—break the surface. This catch is a boon for the museum's marine biologists.

Despite being filter feeders that don't bit or chew, basking sharks have hundreds of teeth. Photo by David Paul

Right now, the head and fins are being preserved to form a full-size replica. To find out how you actually do this, we had a chat with Museum Victoria's Senior Curator of Ichthyology, Martin Gomon, and its Senior Collection Manager of Vertebrate Zoology, Di Bray.

"Just like with any new project, we just about wing it," Gomon told VICE.

Once the trawler had alerted Museum Victoria, they basically had to hit the ground running. The Museum Victoria couldn't exactly easily hire the gear that can shift an object of this size—they couldn't dial for an airlift, let alone have the space to dump the fish in or around Museum Vic's facilities. But in the space of a night, a team of five was organized and on its way to Portland the following morning.

"I don't know if you've ever had to rent a crane, but they're bloody expensive," Gomon explained. "Because we were at the end of a financial year, we had no money in the bank, so it only could lift it off the ship and then drop its head into our trailer."

The frozen head being 3D scanned in Melbourne. Photo by David Paul

Working their way into the night, the team had to manually cut the shark with large butcher's knives out of sheer necessity—they had only a trailer to take pieces of the shark back in.

"People kept asking us, 'Why don't you have chainsaws?' Well, the thought of spraying shark all over the place wasn't a great idea," Gomon said.

The team only took the vital bits—the head, fins, and its "biologicals": stomach contents, vertebrae, as well as skin and tissue samples. The rest of the shark's carcass had to be disposed of in a skip.

The resulting 3D image. Screengrab courtesy of Museum Victoria

Back in Melbourne, the team spent the next two days freezing the head and fins in preparation for a 3D scan—a relatively new process for the museum. Previously, replicas were modeled from 2D images, which would have been much easier to capture when dealing with something the size of a basking shark.

"It's been a real learning curve for us because we don't often deal with objects of that size, but the information in this specimen will be critical to scientists who need it," Gomon said.

An angler fish soaking in embalming fluid

Once this was done, the basking shark was put into a tub of embalming fluid called formalin. In most cases, a formalin bath is sufficient, but the basking shark's size meant the team had to inject the head with five liters of the chemical just to stop the insides from rotting while the solution worked its way through the flesh. "It's really nasty stuff, and if you work long enough with it, it'll preserve you," said Gomon.

The marsupial section

Looking around his office, you can't help but notice the weight of history that surrounds him on a daily basis.

The Melbourne Museum was once the National Museum of Victoria—initially a Victorian-era treasure trove of specimens built with London's Natural History Museum in mind. Owing to Melbourne's initial affluence, the museum completed the city's trifecta of having a university, a national gallery, and a national museum, all within the first 20 years of the town's existence.

Stuffed birds

Now part of Museum Victoria, the 16-million-piece collection encompasses a multitude of rare scientific finds that only a rare few get to see on a regular basis. The basking shark is its latest addition, sitting alongside rooms with Tasmanian tigers and exotic birds dating back to Charles Darwin's voyages.

"As a collection manager, I'm aiming to build the best collection I can so that people in the future can ask questions that we can't even dream of with our specimens," said Bray.

A preserved blobfish

The collection is spread across a number of sites, some in the basement of the Royal Exhibition Building, some in the Melbourne Museum itself, and a few clusters archived in various offsite locations. These aspects of the museum largely go unnoticed. As opposed to the shiny specimens prepped for exhibitions, people like Bray and Gomon are working with colleagues and students from around the globe in these grittier parts of the museum—places where things squelch and platypus feet are stored in jars.

"We hope that in the future we have a facility where the public can see what we do. Our preparers do awesome work—like how they got the shark ready for casting," Bray said.

Museum Victoria's Senior Curator of Ichthyology Martin Gomon and Senior Collection Manager of Vertebrate Zoology, Di Bray

For the moment, Gomon estimates that it'll take two months for the shark to preserve completely. In that time, the preservation team will be readying a full-size replica of the Basking Shark in a feeding position from 3D scans as well as 2D images taken in Portland. For Bray and Gomon, they hope this will unlock a wealth of information for both researchers and the public alike.

All photos by the author unless otherwise specified.

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