Study
Diclofenac residues as the cause of vulture population decline in Pakistan
Oaks, J. Lindsay; Gilbert, Martin; Virani, Munir Z.; Watson, Richard T.; Meteyer, Carol U.; Rideout, Bruce A.
Nature, 2004
Vultures found dead at declining colonies were examined post-mortem, with tissue residues assayed and pathology recorded. Findings were compared against experimental exposure and against birds dying of other causes.
- Studied in
- Gyps bengalensis
- Sample size
- post-mortem examination of vultures found dead across study colonies
Dead vultures showed visceral gout and renal failure, and carried residues of the veterinary anti-inflammatory diclofenac, acquired by feeding on the carcasses of treated livestock. The association held across colonies and was supported by experimental exposure.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Diclofenac residues in livestock carcasses caused the catastrophic decline of Gyps vultures across South Asia.
How NatureHQ reads it
The mechanism is what makes this a scavenging story rather than a poisoning story. A drug harmless to the treated animal, present in a carcass, kills the specialist that eats carcasses — and because a single contaminated carcass is fed on by many birds, a small proportion of treated livestock is enough to collapse a population. The declines exceeded ninety per cent within a decade.
- Field association plus targeted experiment rather than a randomised design, which the situation did not permit.
- Focused on Gyps species in South Asia; sensitivity to the drug varies between vulture lineages.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Nature PortfolioPublished in a Nature Portfolio journal.
Checked against Crossref on 2026-09-28, and they agree on the title, the authors and the year.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-09-03.