2967 is the number which we all started celebrating. India had done well, it seemed, in its conservation efforts with these many tigers in the wild. But with regular decline in habitat, prey base and increase in poaching, do we really think that their survival is still not threatened? Along with these threats, another increasing threat is being ignored by all which has reached an alarming level now. If we don’t act on the massive threat to wildlife that is posed by the Canine Distemper Virus (CDV) which is easily transmitted through infected dogs in and around the sanctuaries and also the feral dog gangs, it may be too late.
A recent study published in Threatened Taxa notes that 86% of the tested dogs around the Ranthambhore National Park in Rajasthan carried CDV antibodies in their bloodstream. This means that the dogs are either currently infected or have been infected sometime in their life and have overcome the disease. This finding points out that there is an increased risk of disease transfer from the dogs to tigers and leopards that live in the park. Isn’t this an alarming situation wherein tigers and leopards are often seen trespassing human habitats and dogs being one of the favourites of leopards. CDV is an airborne disease. Hence, the chance of a wild animal, coming in contact with a CDV-infected dog, of getting infected is also high.
Very few studies, however, have been carried out to gain an insight into the prevalence of the disease in India, particularly in the wild. CDV is the etiological agent of one of the most infectious diseases of domestic dogs. With the aim of exploring the threat CDV poses for tigers, a preliminary assessment was carried out to determine its prevalence from villages near Ranthambhore National Park in Rajasthan, India. Free-roaming dog populations within a 4-km-radius of the park’s periphery were tested for antibodies against CDV. The seroprevalence of CDV antibodies in the sampled dogs was 86%, indicating the probability of the dogs acting as a reservoir and having been exposed to CDV in the past. The seroprevalence of CAV antibodies was 44.23% and CPV antibodies was 95.19%. This could threaten the tiger and leopard populations in the park. It is, therefore, crucial to assess disease threats at the domestic-wildlife interface and to establish management strategies for more effective conservation practices in the landscape.
Last year, Gir lost around 20-odd lions infected with CDV wherein again the demarcation of the sanctuary and the villages is negligible and often the prides are seen roaming in human habitats which increases the chances of spreading of CDV.
In 2001, a few tigers in Russia started to show signs of obvious distress. The endangered Amur (or Siberian) tigers (Panthera Tigris Altaica) were underweight, weak, disoriented and incapable of hunting as a result. At least four of the big cats had to be put down after they wandered into towns in search of food. One mother left behind her three-week-old cubs which had already starved to death.
Few years ago, the cause of this mysterious behaviour was uncovered: The tigers had contracted canine distemper virus (CDV), a usually fatal viral disease that causes a wide range of symptoms including fever, diarrhoea, laboured breathing, dehydration and seizures. The tigers probably caught the disease from eating infected domesticated dogs or from any of the other carnivores present in the Russian wilderness.
Similarly, in 2017, three cubs rescued and rehabilitated in Bandhavgarh and even littered with the help of a dummy tigress died of Parvovirus. How the cubs reared in an quarantined area got infected with Parvovirus is still unknown.
Managing any disease in wildlife is extremely difficult, but preventive steps can be taken by the forest departments of tiger reserves and sanctuaries. These dogs are free ranging and not owned by anyone in the villages around fringes of the forests. The government should take initiative along with NGO’s by organising vaccination and sterilisation programmes for these dogs in the fringes. Its high time the government takes this disease seriously and more studies for collecting data base and plans to eradicate this disease from the fringes of the sanctuaries are carried out on a priority basis. Or else, all felines in the wild will be facing a grave threat.
Few NGO’s have already started working on animal birth control programmes specially for the strays in the fringes of sanctuaries along with vaccination. But they need more government support to reach the goal of eradication of CDV from the fringes of the sanctuaries.
(The writer is a wildlife enthusiast and has worked in the conservation field)