By Anoop NR
With a featherless head and neck along with a large hooked beak, vultures have unique adaptations for scavenging dead animals. Vultures play a vital role in many ecological processes such as eliminating carcasses, controlling the number of other scavengers and epidemic pathogens. They are in severe decline across the globe due to various anthropogenic causes, and 16 of 23 vulture species found globally are currently categorised as threatened due to the risk of extinction.
Once, vultures were common in India, especially in the Central and North Indian states owing to the easy availability of the livestock carcasses. The accidental poisoning by diclofenac, which was used to treat domestic cattle, however, led to an unprecedented decline in vulture populations. This issue turned out to be a huge consternation among biologists.
The sudden population decline of vultures led to various ecological and social problems. The vultures belonging to Gyps genus were the most affected among all and four species of Gyps vultures are now categorised as Critically Endangered due to the high possibility of extinction from the wild. Now in the phase of extinction, actions have been taken such as the ban on the veterinary use of diclofenac. Furthermore many captive breeding centres for vultures have also been initiated.
Despite the rapid population decline of vultures across their distribution range, the Moyar valley and adjacent forests around the Nilgiri plateau have sustained a handful number of these birds possibly because of the absence of diclofenac from this region. There are four species of vultures found in Moyar of which three species are critically endangered, such as Oriental White-backed Vulture, Indian Long-billed Vulture, and Red-headed Vulture. The endangered Egyptian vulture is also an occasional visitor to the valley.
The White-backed Vulture breeds in two colonies along the riparian forests of the Sigur plateau. They mostly prefer to nest in the large Terminalia cuneata trees. The cliff-nesting Long-billed Vulture also breeds in some of the cliffs here. The vulture population managed to sustain themselves in the valley despite a rapid population decline in the continent, in turn, making a vital source population to re-establish from the areas where these birds are declining or devastated.
In the recent past, the Moyar valley was brought under shifting cultivation and was under severe grazing pressure from the cattle pens or locally called ‘Patties’ that operated in the region. Carcasses from these cattle pens, however, ensured a food source for the vultures at the time. The recent ban on livestock grazing and local hunting along with strict protection measures have improved the herbivore and carnivore density in the area and now wild ungulate carcasses ensure food availability for vultures. At this point, the density of large predators and their prey plays a vital role in the survival of vultures.
Currently, the major threat to the survival of vultures in the valley is the retaliatory poisoning of livestock carcasses by cattle owners to eliminate large carnivores which may kill their livestock. Since vultures are colonial, poisoning of one carcass may lead to the death of a large number of vultures at a time. The magnitude and extent of population losses in other parts of the country make it increasingly important to think about how best we can manage and conserve the remaining vulture population in the Moyar valley.
About the Author:
Anoop NR Joined ATREE PhD program in 2015. For his PhD, he is studying the landscape changes and its impact on Asian elephants in Wayanad plateau of the Nilgiri landscape, Western Ghats. He is fascinated in observing and spending time in the wild especially in the wet evergreen forests. He also enjoys playing football.