Bombay Natural History Society

About: Bombay Natural History Society is a archive organization based out in Mumbai, India. It is known for research contribution in the topics: Population & Gyps. The organization has 133 authors who have published 228 publications receiving 4875 citations. The organization is also known as: BNHS.

Diclofenac poisoning as a cause of vulture population declines across the Indian subcontinent

Abstract: Summary 1 Rapid population declines of the vultures Gyps bengalensis, Gyps indicus and Gyps tenuirostris have recently been observed in India and Pakistan, continuing at least up to 2003 Surveys indicate annual rates of decline of 22–50% for G bengalensis and G indicus during 2000–03 Previous studies in Pakistan have shown that the non-steroidal anti-inflammatory drug diclofenac causes renal failure and is lethal to G bengalensis when it feeds on the carcass of a domestic animal that received a normal veterinary dose shortly before death In Pakistan, diclofenac poisoning was found to be by far the most frequent cause of death 2 A simulation model of vulture demography, described in this paper, demonstrated that the observed rates of population decline could be caused by contamination with a lethal level of diclofenac in a small proportion (between 1 : 130 and 1 : 760) of ungulate carcasses available to vultures 3 Proportions of adult and subadult vultures found dead or dying in the wild that had signs of diclofenac poisoning were similar to the proportions of deaths expected from the model if the observed population decline was due entirely to diclofenac poisoning The proportion of the excess mortality required to cause the observed population declines that could be attributable to diclofenac was estimated to be between 71% and 100%, depending on model assumptions However, across all or most of the plausible range of assumed values for adult survival, the upper 95% confidence limit for the proportion of excess mortality due to diclofenac was 100% Hence, available data are consistent with diclofenac poisoning being at least the major cause, and possibly the only cause, of rapid population declines of Gyps vultures across the Indian subcontinent 4 Synthesis and applications We recommend that urgent action is taken in the range states of the three currently threatened vulture species to prevent the exposure of vultures to livestock carcasses contaminated with diclofenac Research is also needed to identify alternative drugs that are effective in livestock and safe for vultures Efforts should also be made to raise awareness, among veterinarians, pharmacists, livestock owners and the general public, of the problem of diclofenac contamination and the availability of safe alternatives Captive holding and breeding of vultures until diclofenac is controlled is recommended as a precaution to ensure the long-term survival of the threatened species and to provide a stock of birds for future reintroduction programmes

Diclofenac poisoning is widespread in declining vulture populations across the Indian subcontinent.

Abstract: Recent declines in the populations of three species of vultures in the Indian subcontinent are among the most rapid ever recorded in any bird species. Evidence from a previous study of one of these species, Gyps bengalensis, in the Punjab province of Pakistan, strongly implicates mortality caused by ingestion of residues of the veterinary non-steroidal anti-inflammatory drug diclofenac as the major cause of the decline. We show that a high proportion of Gyps bengalensis and G. indicus found dead or dying in a much larger area of India and Nepal also have residues of diclofenac and visceral gout, a post-mortem finding that is strongly associated with diclofenac contamination in both species. Hence, veterinary use of diclofenac is likely to have been the major cause of the rapid vulture population declines across the subcontinent.

Removing the Threat of Diclofenac to Critically Endangered Asian Vultures

Abstract: Veterinary use of the nonsteroidal anti-inflammatory (NSAID) drug diclofenac in South Asia has resulted in the collapse of populations of three vulture species of the genusGyps to the most severe category of global extinction risk. Vultures are exposed to diclofenac when scavenging on livestock treated with the drug shortly before death. Diclofenac causes kidney damage, increased serum uric acid concentrations, visceral gout, and death. Concern about this issue led the Indian Government to announce its intention to ban the veterinary use of diclofenac by September 2005. Implementation of a ban is still in progress late in 2005, and to facilitate this we sought potential alternative NSAIDs by obtaining information from captive bird collections worldwide. We found that the NSAID meloxicam had been administered to 35 captiveGyps vultures with no apparent ill effects. We then undertook a phased programme of safety testing of meloxicam on the African white-backed vultureGyps africanus, which we had previously established to be as susceptible to diclofenac poisoning as the endangered AsianGyps vultures. We estimated the likely maximum level of exposure (MLE) of wild vultures and dosed birds by gavage (oral administration) with increasing quantities of the drug until the likely MLE was exceeded in a sample of 40G. africanus. Subsequently, sixG. africanus were fed tissues from cattle which had been treated with a higher than standard veterinary course of meloxicam prior to death. In the final phase, ten Asian vultures of two of the endangered species(Gyps bengalensis,Gyps indicus) were dosed with meloxicam by gavage; five of them at more than the likely MLE dosage. All meloxicam-treated birds survived all treatments, and none suffered any obvious clinical effects. Serum uric acid concentrations remained within the normal limits throughout, and were significantly lower than those from birds treated with diclofenac in other studies. We conclude that meloxicam is of low toxicity toGyps vultures and that its use in place of diclofenac would reduce vulture mortality substantially in the Indian subcontinent. Meloxicam is already available for veterinary use in India.

Causes and Effects of Temporospatial Declines of Gyps Vultures in Asia

Abstract: There are eight species in the genus Gyps : Gyps africanus , G. coprotheres, and G. rueppellii in Africa; G. bengalensis , G. indicus , G. tenuirostris , G. himalayensis in Asia; G. fulvus in Europe, Africa, and Asia. The ranges of many of these species overlap, and wintering G. fulvus overlap with several resident species in Asia and Africa (Fig. 1). Gyps species share a similar feeding ecology, scavenging the soft tissues of large mammals, usually ungulates. They tend to be colonial nesters and communal feeders, feeding alongside conspecifics and other vulture species. Densities of Gyps vultures can be high in areas with suitable breeding habitat and abundant carrion. An extreme example is G. bengalensis , which often lives in close association with humans. During the 1970s and early to mid-1980s, densities of 12 nests/km 2 were recorded at Keoladeo National Park, Rajasthan, India (Prakash 1989), and there were nearly 3 nests/km 2 in the city of Delhi (Galushin 1971), where flocks of several thousand birds were present at carcass dumps. As recently as 1985, G. bengalensis was regarded as “possibly the most abundant large bird of prey in the world” (Houston 1985). Despite Gyps population declines across Southeast Asia, until recently only one species of Africa, G. coprotheres, was considered globally threatened (vulnerable; BirdLife International 2000), largely because of the indiscriminate use of poisons in southern Africa (Mundy et al. 1992). Following the recent population crash in Gyps species across the Indian subcontinent, three other species, G. bengalensis, G. indicus, and G. tenuirostris , are now listed as critical ( BirdLife International 2000), placing them among the most threatened birds in the world.