14 DAY TRIAL // Those of you who've been keeping an eye on the news probably know that tigers aren't exactly having the time of their lives these days. They've lost a large portion of their natural habitat and plenty of people are still hunting them.
As if the world's remaining tigers didn't already have enough trouble to deal with, a new paper in the scientific journal PLOS ONE argues that a virus now threatens to push this species even closer to extinction.
A seriously nasty little fellow
The microorganism that environmental group the Wildlife Conservation Society says has the potential to wipe out the world's remaining tiger population is known to the scientific community as the canine distemper virus.
It can infect all sorts of animals, dogs, tigers, otters, skunks, and hyenas included, and studies have shown that it has a mortality rate of as much as 50%. What's more, experts say that this disease is highly contagious.
When infected with the canine distemper virus, an animal can display symptoms such as high fever and watery discharge from its eyes and its nose. Vomiting and diarrhea can also occur, specialists say.
As the disease progresses, a tiger and any other animal carrying the virus in its body stands to experience severe seizures and even delirium. In some cases, the disease can lead to paralysis.
Although the canine distemper virus was discovered decades ago, researchers have not yet managed to find a cure for this disease. Simply put, the animals that contract the virus and start developing symptoms have little chance to survive.
A major threat to tigers living in the wild
The new paper in the journal PLOS ONE focuses on the Amur tiger population in Russia's Sikhote-Alin Biosphere Zapovednik. In this corner of the world, tiger numbers dropped from 38 to 9 between the years 2007 and 2012.
More precisely, the wildlife researchers who conducted this investigation say that, in the years 2009 and 2010 alone, the region lost 6 adult tigers, of which some were found dead and others simply disappeared. The canine distemper virus was found in the bodies of 2 of the dead tigers.
Based on these findings, researchers concluded that, although not the only culprit, the canine distemper virus surely helped bring down the tiger population in Russia's Sikhote-Alin Biosphere Zapovednik. To further investigate the matter, they turned to computer modeling.
It was thus discovered that small tiger populations, i.e. comprising up to 25 individuals, are 1.65 times more likely to decline over the course of 5 decades if canine distemper virus infections are also factored in. Besides, the presence of the virus in Russia's Sikhote-Alin Biosphere Zapovednik is argued to have made the tiger population some 55.8% more vulnerable to extinction.
Safeguarding the world's remaining tigers
In light of these findings, specialists urge that efforts to keep this species from falling off the biodiversity map focus not just on protecting the tigers' natural habitat and keeping poachers away from these felines, but also on tacking the canine distemper virus.
“Tigers face an array of threats throughout their range, from poaching to competition with humans for space and for food. Consequently, many tiger populations have become smaller and more fragmented, making them much more susceptible to diseases such as CDV [canine distemper virus].”
“While we must continue to focus on the primary threats of poaching and habitat destruction, we now must also be prepared to deal with the appearance of such diseases in the future,” says Dale Miquelle with the Wildlife Conservation Society.
Since the disease appears to hit small tiger populations harder than it does larger ones, specialists recommend that efforts be made to help the felines come together more easily. Besides, it's important to figure out how and why the virus infects tigers living in the wild.