Stopping Devil Facial Tumor Disease
Vaccination might seem like the easiest way to stop Devil Facial Tumor Disease (DFTD) from infecting more Tasmanian devils. Cancer research for humans focuses a lot of time and funding on searching for a cure, so why not do the same for the devil? In short, time and funding is precisely what scientists studying DFTD lack. Already, the Tasmanian devil preservation program is cash strapped. Acquiring additional funding for the work necessary to create a vaccine might be an insurmountable hurdle. And even if scientists found an effective medicine, inoculating all the Tasmanian devils in the wild would be a difficult -- if not impossible -- undertaking.
Breeding the disease susceptibility out of Tasmanian devils might be a more feasible route. DFTD has affected Tasmanian devils in the eastern part of the island the most, where the population is the highest. Scientists hoped that a devil named Cedric from the west held the key to halting the cancer. Immunologists injected the Tasmanian devil with live tumor cells, and after five months, Cedric's body produced antibodies to fight the virus. Scientists therefore hypothesized that Cedric might have a slightly different genetic coding that triggers a stronger immune response. By cracking that genetic code, scientists could develop a potential method for identifying and quarantining other resistant devils. After reintroduction into the wild, the immune devils would breed and form a stronger population.
A tracking project in the northwest corner of the island has also found that the spread of DFTD has diminished somewhat, which may have to do with the slight genetic variation Cedric exhibited [source: Clausen]. In case the wild species collapses from DFTD, the Tasmanian government hopes to assemble a captive breeding population of 1,500 resistant devils. The beginning stages of that federal breeding program that has started on the Tasman-Forestier Peninsula. Wildlife researchers trap and euthanize infected Tasmanian devils and tag healthy ones. So far, their efforts have resulted in an 8 percent drop in disease prevalence rate [source: Trofimov]. The Tasman-Forestier Peninsula was chosen as the project location because it attaches to the main part of Tasmania by only a narrow bridge. If the project is deemed a success, the government may fence off the peninsula from the mainland to protect the healthy devils from DTFD.
As of fall 2008, DFTD had decimated at least half of the devil population. If the species were allowed to disappear entirely, it would have a deep impact on the island's ecology. The carnivorous marsupials keep the cat and fox population in check. No more devils would mean a spike in the number of those predators, which would spell the demise of more than a dozen other species, including some birds and lizards [source: Hansford].
The outlook for Tasmanian devils grew even dimmer in December 2008 when Cedric, the potentially immune devil, developed two cancerous tumors on his face. With that news, scientists didn't completely accept defeat, but it has forced them to revise their strategy. There's still a chance that captive breeding could produce a stronger, more disease-resistant generation. But in such a limited gene pool, the DFTD crisis could be too much for the pugnacious devils to fight off.
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More Great Links
- "Bedeviled by Disease." The Washington Post. April 15, 2008. (Dec. 17, 2008) http://www.washingtonpost.com/wp-dyn/content/article/2008/04/14/AR2008041402486.html
- Clausen, Lisa. "Lucky Devils?" TIME South Pacific. May 19, 2008. (Dec. 17, 2008)http://www.time.com/time/magazine/article/0,9171,1738371,00.html
- "Dying Tasmanian devils turn to teen pregnancies." New Scientist. July 19, 2008. (Dec. 17, 2008)http://www.newscientist.com/article/mg19926655.600-dying-tasmanian-devils-turn-to-teen-pregnancies.html
- Hansford, Dave. "Tasmanian Devils Named Endangered Species." National Geographic. May 21, 2008. (Dec. 18, 2008)http://news.nationalgeographic.com/news/2008/05/080521-endangered-devils.html
- Holtcamp, Wendee. "Tasmania's Devil of a Problem." National Wildlife. June/July 2008. (Dec. 17, 2008)http://www.nwf.org/NationalWildlife/article.cfm?issueID=122&articleID=1598
- Owen, David and Pemberton, David. "Tasmanian Devil." Allen & Unwin. 2005. (Dec. 17, 2008)http://books.google.com/books?id=Hv0yIz70P-4C
- "Possible vaccine for dying devils." Australian Geographic. July - September 2008.
- Quammen, David. "Contagious cancer: The evolution of a killer." Harper's. April 2008. (Dec. 17, 2008)http://harpers.org/archive/2008/04/0081988
- Trofimov, Yaroslav. "Tasmanian Devils Get Reprieve in Australia's Old Penal Colony." The Wall Street Journal. May 28, 2008.