Justification of Red List Category
This species is classified as Critically Endangered because it has suffered an extremely rapid population decline as a result of mortality from feeding on carcasses of animals treated with the veterinary drug diclofenac.
A population estimate of c.45,000 individuals has been extrapolated from 2007 survey results published by Prakash et al. (2007), who recorded 337 individuals along 18,000 km of road transects. This very roughly equates to 30,000 mature individuals.
Survey results indicate that declines throughout the Indian Subcontinent probably began in the 1990s and were extremely rapid, resulting in an overall population decline of greater than 97% over a 10-15 year period.
Gyps indicus breeds in south-east Pakistan and peninsular India south of the Gangetic plain, north to Delhi, east through Madhya Pradesh, south to the Nilgiris, and occasionally further south (Collar et al. 2001). The species was first recorded in Nepal in 2011 (Subedi and DeCandido 2013). It was common until very recently, but since the mid-1990s has suffered a catastrophic decline (over 97%) throughout its range. This was first noticed in Keoladeo National Park, India (Prakash et al. 2003), where counts of feeding birds fell from 816 birds in 1985-1986 to just 25 in 1998-1999. Just one tiny population in the Ramanagaram Hills of Karnataka is known to remain in inland southern India, and it is rare elsewhere within its former range (Prakash et al. 2007). Data indicates that the rate of population decline of G. tenuirostris and G. indicus combined has now slowed in India (Prakash et al. 2012).Extensive research has identified the non-steroidal anti-inflammatory drug (NSAID) diclofenac to be the cause behind this rapid population collapse (Green et al. 2004, Oaks et al. 2004a, Shultz et al. 2004, Swan et al. 2005). This drug, used to treat domestic livestock, is ingested by vultures feeding on their carcasses leading to renal failure causing visceral gout (Oaks et al. 2004a,b; Swan et al. 2005, Gilbert et al. 2006). It is now rare in Pakistan, and although a colony of 200-250 pairs was discovered in 2003 in Sindh Province (A. A. Khan in litt. 2003). In 2007, the total Indian population, based on extrapolations from road transects, was estimated at 45,000 individuals, with a combined average annual decline for this species and G. tenuirostris of over 16% during 2000-2007 (Prakash et al. 2007). It is estimated that its relative abundance in Pakistan declined by 61% between 2003-2004 and 2006-2007, this was followed by a 55% increase by 2007-2008 (Chaudhry et al. 2012).
It is found in cities, towns and villages near cultivated areas, and in open and wooded areas. This species feeds almost entirely on carrion, and often associates with White-rumped Vulture G. bengalensis when scavenging at rubbish dumps and slaughterhouses. It nests almost exclusively in colonies on cliffs and ruins, although in one area, where cliffs are absent, it has been reported nesting in trees. Vultures also play a key role in the wider landscape as providers of ecosystem services, and were previously heavily relied upon to help dispose of animal and human remains in India.
By mid-2000, Gyps vultures were being found dead and dying in Pakistan and throughout India, and major declines and local extirpations were being reported. The anti-inflammatory drug diclofenac, used to treat domestic livestock, has been identified as the cause of mortality, with renal failure resulting in visceral gout in the vast majority of examined vultures (Oaks et al. 2004a, Shultz et al. 2004, Swan et al. 2005, Gilbert et al. 2006). Modelling has shown that to cause the observed rate of decline in the species just one in 760 livestock carcasses need contain diclofenac residues (Green et al. 2004). Despite awareness programmes to educate locals about the association between diclofenac and vulture mortality, a survey in Nepal indicated that the vast majority of people still do not link diclofenac use to a decline in vulture populations (Paudel 2008), potentially leading to a slower uptake of meloxicam (a safe alternative). A second veterinary drug in use in India, ketoprofen, has also recently been identified to be lethal to the species, and measurements of residue levels in ungulate carcasses in India indicates that concentrations are sufficient to cause vulture mortalities (Naidoo et al. 2009). Other likely contributory factors are changes in human consumption and processing of dead livestock (which have occurred in response to the collapse in vulture numbers), poison and pesticide use, and possibly avian malaria (Poharkar et al. 2009), but these are probably of minor significance.
Conservation Actions Underway
CITES Appendix II. It has been reported from many protected areas across its range. The Indian government has now passed a bill banning the manufacture of the veterinary drug diclofenac that has caused the rapid population decline across the Indian subcontinent; their aim was to phase out its use by late 2005 (Gilbert et al. 2006, Swan et al. 2006), although its sale has not been banned and it is likely to remain in widespread use for several years. Similar laws banning import and manufacture of diclofenac are now in place in Nepal and Pakistan. A letter from the Drug Controller General of India in 2008 warned more than 70 drugs firms not to sell the veterinary form of diclofenac, and to mark human diclofenac containers 'not for veterinary use' (BirdLife International 2008). In October 2010, the government of Bangladesh banned the production of diclofenac for use in cattle, and the distribution and sale of the drug were due to be outlawed there during the first half of 2011 (M. M. H. Khan in litt. 2010). Efforts to replace diclofenac with a suitable alternative are ongoing; drug companies have now developed meloxicam, an alternative to diclofenac, which has been tested on Gyps vultures with no ill-effects.
The Report of the International South Asian Vulture Recovery Plan Workshop in 2004 gave a comprehensive list of recommendations including establishing a minimum of three captive breeding centres each capable of holding 25 pairs (Bombay Natural History Society 2004) - ultimately at least 150 pairs of the three species should be held in captivity to ensure sufficient birds are available to re-establish wild colonies in the future (Lindsay 2008). Captive breeding efforts are ongoing and during 2008-2009 there were 71 individuals in captivity at two captive breeding centres in India (Pain et al. 2008, Bowden 2009). In 2009, captive birds laid eggs, raising hopes that they will successfully breed in captivity in the near future (Bowden 2009). By November 2011 there were 83 individuals in captivity at two centres, 11 of these were juveniles that had successfully fledged (Bowden et al. 2012). SAVE (Saving Asia's Vultures from Extinction) has developed the concept of Vulture Safe Zones; areas (with a minimum of 100 km radius, equating to 30,000 km2) around important vulture breeding colonies, where education and advocacy efforts are focused on eliminating the use of diclofenac and other vulture-toxic drugs (Galligan 2013, Mukherjee et al. 2014). There are currently 12 provisional Vulture Safe Zones being established in India, Nepal, Pakistan and Bangladesh (Mukherjee et al. 2014). These areas will provide a safe environment into which birds bred in captivity can be released (Bowden et al. 2012).
In 2012 the governments of India, Pakistan, Nepal and Bangladesh adopted a number of priority actions for the conservation of vultures, proposed by SAVE. These include banning large multi-dose vials of human diclofenac, testing other NSAIDs for toxicity to vultures and expanding the Vulture Safe Zones initiative (Galligan 2013).
Conservation Actions Proposed
Identify the location and number of remaining individuals and identify action required to prevent extinction. Measure the frequency of diclofenac treated carcasses available to vultures. Support the ban on the veterinary use of diclofenac, and support species management or restoration, as needed. Initiate public awareness and public support programmes. Monitor remaining populations. Support captive breeding efforts at a number of separate centres. Manage genetic stock in the captive-bred population (Bowden et al. 2012). Promote the immediate adoption of meloxicam as an alternative to diclofenac. Test other non-steroidal anti-inflammatory drugs (NSAIDs) to identify additional safe alternative drugs to diclofenac and also other toxic ones. Two drugs, aceclofenac and ketoprofen, are known to be toxic to vultures, approximately another 10 drugs need to be tested (Galligan 2013). Restrict the size of diclofenac vials sold for human use to make them less practical to use for veterinary purposes and take action against companies that fail to comply with the diclofenac ban (Cuthbert et al. 2011).
92 cm. Typical Gyps vulture. Robust, strong features giving eagle-like bearing. Perched adults have pale-yellowish bill and cere; pale eyerings; large white neck-ruff; and buff back and upperwing coverts. The stout blackish neck has pale down. Juveniles have dark bill with pale culmen; pinkish head and neck covered in pale down and dingy heavily streaked underparts. In flight thighs are heavily feathered and concolourous with the rest of the underparts. Similar spp. Told from the allopatric and distinctive Slender-billed Vulture G. tenuirostris by robust build, clean plumage, pale bill (in adults) and downy head and neck (juveniles).
Text account compilers
Benstead, P., Bird, J., Butchart, S., Calvert, R., Crosby, M., Symes, A. & Taylor, J.
Cuthbert, R., Gilbert, M., Khan, A., Khan, M., Prakash, V. & Riseborough, R.
BirdLife International (2017) Species factsheet: Gyps indicus. Downloaded from http://www.birdlife.org on 22/09/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 22/09/2017.