The story so far: On October 19, the Tamil Nadu government formed a committee to set up an institutional framework for the effective conservation of vultures. The State is home to four species of vultures — the white-rumped vulture (Gyps bengalensis), long-billed vultures (Gyps indicus), the Asian king-vulture (Sarcogyps calvus) and the Egyptian vulture (Neophron percnopterus).
Which areas in Tamil Nadu have vulture populations?
While there have been reported sightings of vultures in other districts including Dharmapuri; essentially the Nilgiris, Erode and Coimbatore districts are believed to form one of the largest contiguous expanses where vultures are spotted. Home to the nesting sites of three of the four species of vultures seen in the State, the Mudumalai Tiger Reserve, parts of the Nilgiris forest division and the Sathyamangalam Tiger Reserve are crucial strongholds for the vultures in southern India. Occasional migrants such as the Himalayan griffon vulture and the Cinerous vulture are also spotted each year. Tamil Nadu boasts the largest population of vultures south of the Vindhiya Mountain Range.
In the Nilgiris, researchers and forest department officials estimate that there are between 100 and 120 white-rumped vultures, 10 and 15 long-billed vultures and less than 10 Asian king vultures. Though Egyptian vultures are spotted in the Sigur plateau, encompassing the Nilgiris and Erode districts, they are not believed to use the landscape to breed, while researchers still remain unsuccessful in tracing the breeding sites of the critically endangered Asian king-vulture.
Are vulture numbers decreasing?
While the population of the vultures in the Nilgiris, Erode and Coimbatore districts has remained largely stable, experts state that the numbers are still extremely low, and that even a single poisoning event could lead to several of the species going locally extinct, especially the long-billed and Asian king vulture. Over the last few years, breeding seasons have also seen fewer hatchings than is the norm, with experts attributing the cause to lesser availability of prey as well as erratic weather.
Experts also agree that the use of some Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) to treat cattle, such as diclofenac, nimesulide, ketoprofen among others, has led to the crash in vulture populations across India.
What role do vultures play in the local ecosystem?
As scavengers, vultures help prevent the spread of many diseases and can remove toxins from entering the environment by consuming carcasses of dead cattle/wildlife before they decompose. Unfortunately, their tolerance for harmful substances does not extend to man-made drugs.
What are the challenges which impact vultures in the State?
There are multiple. For one, temple tourism in the Sigur plateau is centred primarily around vulture habitats, such as Siriyur, Anaikatty and Bokkapuram. Over the last few years, there have been recorded instances of vultures abandoning nesting sites located too close to temples inside these reserves, with activists calling for strict controls on the amount of people allowed to attend these festivals.
Another threat is the spread of invasive weeds such as the Lantana camara in vulture-landscapes, which hinder the birds from scavenging as their large wing-spans require plenty of open area to safely land and to take to the skies in case of any major threats. Finally, due to the illegal tapping of water along the streams running through these areas, possible climate change, and forest fires, the Terminalia arjuna trees, that many vultures use as nesting sites are disappearing. Only through a multipronged approach of increasing the amount of food available to the birds and managing invasive species can vulture numbers start rebounding, say experts.
What are the steps taken to protect vultures in the State?
The State government has banned the use of diclofenac, a drug, to treat cattle, while there are strict restrictions for the sale of other NSAIDs in the Nilgiris, Erode and Coimbatore districts. Additionally, as the vultures in the Sigur plateau utilise landscapes in neighboring Karnataka and Kerala, experts have called for a synchronous vulture census to accurately identify vulture populations and nesting sites.