This Vaccine Could Save the Tasmanian Devil From Extinction
The fight to save Tasmanian devils just got kicked up a notch.
Last week, 20 captive-bred Tasmanian devils were returned to the wild. While that may not seem to be much of a population bump, it’s a start for the famously snarly marsupials, which have been devastated by a communicable cancer known as devil facial tumor disease.
Since it was first discovered in 1996, the cancer has killed off as many as 90 percent of the animals in many parts of their habitat. With no cure in sight, conservationists resorted to rounding up hundreds of disease-free animals from the wild; they were placed in safe captive-breeding programs located far from the possibility of infection.
Over the past few years, scientists have worked around the clock to figure out how to save the animals, and this release could be the starting point: The devils are not only disease-free but also the first recipients of a new vaccine that may prevent them from catching DFTD.
The 20 inoculated devils were exposed to DFTD in a laboratory setting, after which they produced an immune response—an indication that the vaccine may be effective against the disease.
“This is an excellent outcome, but the real test will be determining whether the vaccine is effective in protecting devils in the wild,” immunologist Greg Woods of the Menzies Institute of Medical Research at the University of Tasmania said in a statement.
Captive-bred devils have been released in the past, but only in regions that do not contain any of their species. This time, they were released into Narawntapu National Park in northern Tasmania—an area that contains wild devils known to carry the disease.
The relocated devils benefited from the work of Elizabeth Reid-Wainscote, an American intern on the ground in Tasmania who is being supported by San Diego Zoo Global. “She’s a behaviorist,” explained Bob Wiese, director of living collections for San Diego Zoo Global. “What she’s been doing is kind of forewarning the wild animals out in the national park that new devils are coming.”
To accomplish that, Reid-Wainscote scattered the captive-born devils’ scat around the park in the weeks prior to the release. This allowed the wild devils to get used to the smell of the new arrivals so they would not perceive them as a threat. The presence of the newcomers’ own scent also made the park feel more welcoming to them when they were released, so they would be more likely to stick around the park.
Now that the release has taken place, the devils will be checked several times over the next 12 weeks. “They’ll be looking to see whether they’re surviving and finding enough food and prey to eat, and if they are being infected by the disease out in the wild,” Wiese said. If the immune response does not remain active, the animals could receive a booster shot to enhance the vaccine’s effectiveness.
“The disease has knocked the devils down quite a bit, which has caused all of their prey species to increase, which affects the environment in all kinds of ways,” Wiese said. “It’s like a chain reaction. One of the ideas is if you get additional devils back out there, can we raise the density of the devils and restore the natural balance.”
The release of disease-free devils is admittedly risky for the animals, but Wiese said it’s also necessary: “The whole point of breeding the devils and maintaining the insurance populations is so you can put them back out in the wild. At some point, you’ve got to take that risk.” He equates the process with similar captive-breeding and release work with species that have been saved from extinction, such as the California condor and the black-footed ferret.
Although Tasmanian devils have suffered terribly over the past 20 years, Wiese said it looks like the work that’s been done to fight the disease is starting to pay off. “I think maybe we’re starting to turn the tide against this thing,” he said.