Racing to Save the Tasmanian Devil 1

How I found out about the terrible but fascinating disease threatening this iconic animal

Two continents call to every American naturalist with their varied and to us exotic natural worlds, Africa and Australia. I’ve never gotten an opportunity to visit Africa, but my opportunity to soak up what Australia has to offer came from a totally unexpected connection.

A Bizarre Disease Appears from Nowhere

I had made friends with Australian student Jenny Marshall, now geneticist Jennifer Marshall Graves, back in my college days. Then in 2015, we got together for the first time in decades in Oceanside, CA, when my husband Greg and I were escaping the Montana winter and Jenny was visiting her daughter in Los Angeles. As Jenny and I strolled along the shore, she talked about a terrible disease DFTD (Devil Facial Tumor Disease), that was ravaging wild populations of the Tasmanian devil. It had already killed off as much as 90% of the devils where it struck.

Greg, Jenny, and Dorothy relax together in Oceanside as Jenny shares some photos on her computer

What I Learned from Jenny

I confess I had avoided learning about DFTD because I’d read of the horror of how it tortured its victims. But as Jenny explained its remarkable biology, I was drawn right in. It’s actually a cancer that can be passed from one individual to another through physical contact. No cancer of this sort, outside of a rare and obscure dog disease, had been seen before.

Then Jenny pleaded—“Come to Australia and write a book about the devils. They are so important in the ecosystem and they are dying off fast. Kids would love learning about them and this weird disease. Stay with us in Melbourne! And I’ll come along to Tasmania and introduce you to the DFTD scientists. Please come!”

How could I resist her enthusiasm? Here’s a chance to visit Australia, and this biological puzzle really called to me as a scientist fascinated by genetics.

“I’ll see if I can make it happen,” I promised. I proposed the topic to a series called Scientists in the Field. I’d already written one successful book (Call of the Osprey) for the series. The publisher bought in on the Tasmanian Devil and I had a deal!

Why is the Tasmanian Devil so important?

Every ecosystem needs “garbage men”, and Tassy devils serve this function especially well in disposing of dead animals, such as roadkill. They do hunt for prey, but scavenging is a big part of their diet.

Tasmanian devils have especially strong teeth, perfect for tearing into and chewing up the carcasses of road kill or prey.

Their robust teeth can cut through the toughest skin on a carcass, opening it up for other scavengers to feast. Their especially strong jaws and thickened molars allow them to crack big bones and crunch them up. Once devils get into a roadside carcass, nothing is left unconsumed. When devils are absent, it’s difficult for other scavengers to get through the tough skin of animals like wombats, that have very thick-skinned rumps.

What Is Devil Facial Tumor Disease?

Normally, if a living body encounters cells from another individual, it recognizes them as “foreign” and quickly sends out immune system cells to destroy them. For this reason, the immune system of a human patient getting an organ transplant must be suppressed. So the discovery of a cancer that can bypass the immune system was a big surprise.

DFTD can be passed on when an infected devil encounters a healthy one while feeding on road kill or other dead animals. So an infected devil can pass the disease on to another when they battle over a carcass. This is probably the common way the disease is transmitted.

This small tumor in the devil’s mouth will grow.

Once the cells get into a new victim, they divide and divide, invading the mouth and traveling through the blood to other parts of the body, forming tumors. The victims have no defense and die within a few months.

This map of the eastern part of Australia shows the place Greg and I visited on the Australian mainland in dark red lettering. We landed in Sydney and spent time there, the up north to Cairns and Kuranda. After flying south to Melbourne, we visited Healesville Sanctuary while staying with Jenny’s family near Melbourne. I’ll write about our northern visit to the rainforest, Great Barrier Reef, and more in a later post. There’s lots to tell you!

Observing Australia’s Diverse Wildlife

After spending time in Sydney and Queensland, Greg and I arrived in Melbourne to stay with Jenny and her husband John in the nearby countryside while beginning my devil research. I love Jenny’s place—the spacious yard is home to birds I’d never seen before. It was late September, and our house in Montana was quieting down into autumn. But here in Australia, spring was beginning to rule, with birdsong and blooming flowers and warm breezes.

Jenny loves Spring. One of the joys of the season for her is harvesting tender asparagus spears from her garden. We enjoyed them that evening at the dinner table.

I soaked up the springtime atmosphere and loved watching the Australian avian residents go about their lives.

An Australian magpie struts along the lawn

This lovely parakeet enjoys the shade of a tree by the house

A kookaburra perches on a branch by the driveway

But it was time to get busy learning about the devil. Jenny drove us further out into the countryside to visit the Healesville Sanctuary, home to many Australian animals and an important breeding center for the Tasmanian devil. Two “ambassadors,” Tierney and Sassafrass, greeted us from their spacious and secure space by the visitor pathway.

Tierney and Sassafrass are curious about visitors, so when people show up, they come to the front of their enclosure to check out the new folks. In nature, the devils sleep during the day and hunt for food at night, but these ambassadors have learned to reverse their natural routine.

Healesville’s Devil Program

Peter Comber, a member of the staff working with Healesville’s devils, showed us how the breeding program keeps track over time. Each devil has a card on display indoors that shows its unique pattern of white markings in its almost black coat.

On the cards, black and white are reversed. Each animal’s pattern is shown from four different views. Dozens and dozens of devils have gone through this breeding program.

Here are Sassafras and Tierney’s cards. They are both to old to breed, but they are still in the system.

Sassafrass and Tierney experience lots of human activity, and noise from sanctuary visitors. Their job is to show people that Tassy devils are not vicious creatures but are just curious animals.

Devils used for breeding, however, are kept in fenced enclosures in a very quiet part of the sanctuary that’s not open to the public. The goal is to breed disease free animals that aren’t used to people. Their food and water are provided without human contact. They can be released in the wild without thinking of humans as a source of food.

Each breeding enclosure is a roomy 18 acre space, with lots of vegetation and a locked gate that shows the card for the breeding female in the enclosure.

The water system in each enclosure is automatically operated to keep fresh water available at all times. Food is derived by truck during the daytime, when the devils are asleep.

After touring the breeding area, we returned to the public part of the sanctuary, where many native species were kept for public view. For people from the States, this place held special value, as all the animals were Australian—no lions or wolves or elephants, just native birds and marsupial mammals.

The spiny echidna is just one of the animals we saw at Healesville. It’s a rare kind of mammal that actually lays eggs. It waddles along, sniffing for small insects to eat.

Time for Tasmania!

I’ll show you more Aussie wildlife in a later post, but for now I’m sticking with the Tassie devil. There’s so much to learn!

How do the devils live day to day in the wild? What about their mating behavior? Are any of them able to fight back from DFTD? What can we do to help them fight off the disease? Can we develop a vaccine?

Jenny and her colleagues had set up appointments in Tasmania for me to learn about this key animal in the ecosystem and to see first hand how scientists are working to help it survive, so it was time to head to Tasmania. I’ll bring you along as I continue my journey in my next post.

Upon arrival on Tasmania, I can see that saving the devil is a big priority for this island, and I gladly make my own donation to the Appeal.