Diclofenac Threat to Vultures

Why in news?

The 104 birds bred at Rani, Assam face a serious threat by Diclofenac drug used in cattle.

How is vulture population in India?

India hosts 9 vulture species, 5 of them the highly endangered Gyps species.
Assam is naturally a suitable habitat for vultures.
It is home to 6 species, including winter visitors from the Himalayas — the Himalayan and Eurasian griffons.
The Vulture Conservation Breeding Centre (VCBC) in Assam at Rani, Guwahati has 104 vultures, brought in as chicks.
It has 30 adults and sub-adults: all oriental white-backed and slender-billed.
These are 2 of the 6 species found in Assam that are old enough to be set free.

The vulture population in Assam is presently battling toxic chemicals in livestock carcasses, due to Diclofenac use.

How does diclofenac affect vultures?

The digestive system of vultures is so evolved.
This makes it possible to tolerate bacteria and natural toxins in putrefying meat.
But they are vulnerable to chemicals such as diclofenac.
Diclofenac present in the carcasses of cattle, injected as a painkiller, finds way into the vulture.

What are the challenges in eradication?

Diclofenac - Diclofenac for veterinary use was banned in 2005 but it was continued to be made for humans.
BNHS pressured the government into banning the vials (containers) of 30 ml or more in 2015.
Humans need 3-5 ml while only 30 ml or more works for cows.
But untrained veterinarians use the 30 ml vials for veterinary use, with fatal consequences for vultures.
The last of the 2015 stocks of the big vials expire by December 2018.
This is thus delaying the freedom (release) for adult vultures being reared in captivity in the State.
Pesticides - Even after the expiry of diclofenac stocks, there is no guarantee that the birds will be safe.
The rampant use of pesticides by farmers and more than 70,000 tea gardens is another concern.
Villagers generally poison carcass of dead animals with pesticides to kill dogs, jackals and leopards that are a danger to livestock.
Unfortunately, vultures that feed on these carcasses become the unintended victims.
Recently, around 30 vultures, most of them Himalayan griffons, died in Assam, after feeding on the poisoned carcass of a goat.

Life cycle - Vultures take time to mature, pair for life, breed once a year, and live up to 70 years.
This extended cycle make captive breeding efforts challenging.

What are the efforts to address this?

The VCBC takes various efforts to save the birds by reducing their exposure to the fatal drug.
Mutton is the only food given at the VCBC and goats are kept for 10-12 days before the feeding.
This is to ensure that traces of any toxic painkiller or other chemicals are flushed out.

Source: The Hindu

Quick Fact

VCBCs

The VCBCs are set up by the Bombay Natural History Society (BNHS) in association with State Forest Departments.
The Vulture Conservation Breeding Centre (VCBC) in Assam is at Rani, about 30 km west of Guwahati.
It is one of the 4 Vulture Conservation Breeding Centres in India.
The other three are in Pinjore (Haryana), Buxa (West Bengal), Bhopal (Madhya Pradesh).