Protecting vultures across Asia and Europe

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Dr Mark Taggart from UHI’s Environmental Research Institute developed analytical chemistry tools to investigate the threat posed to vultures by certain veterinary drugs, influencing government legislation and ongoing international conservation work.

Unit of assessment | Earth Systems and Environmental Sciences

committee of vultures
With thanks to Chris Bowden, RSPB

Vultures are nature’s carrion disposal system, preventing the increase and spread of lethal pathogens in the environment. However, ‘Old World’ vultures are the most threatened group of terrestrial migratory birds on the planet. Since the mid-1990s, South Asia’s three Gyps vulture species have declined to near extinction levels. This has mainly been due to unintentional poisoning by a veterinary drug called diclofenac, one of several NSAIDs (non-steroidal anti-inflammatory drugs) now known to cause vulture mortality.

In 2006, India, Pakistan and Nepal all banned veterinary diclofenac as it was causing widespread poisoning of vultures who fed on carcasses of treated farm animals. Bangladesh also banned its use in 2010. Taggart and other scientists worked closely with conservationists led by the RSPB (Royal Society for the Protection of Birds) to show the safety of – and then promote the use of – an alternative ‘vulture-safe’ NSAID called meloxicam. However, the higher cost of meloxicam meant illegal use of diclofenac might continue. It was critical to ensure the switch to meloxicam happened, to secure vulture population recovery.

To provide robust research evidence, between 2004 and 2014 Taggart analysed drug residues in livers from animal carcasses available to vultures across India. He screened >6,000 carcasses (cattle, water buffalo, sheep, goats) for multiple NSAIDs. This showed that diclofenac use had declined since the 2006 ban and that meloxicam use had increased, reducing the overall risk to vulture populations by two-thirds. However, it also showed that diclofenac was still in illegal use in India, continuing the threat to vulture populations.

This evidence was used by the collaborative partnership SAVE (Saving Asia’s Vultures from Extinction), which includes UHI, to lobby the Indian government to tighten laws around the illegal use of diclofenac in livestock, with new laws passed in 2015 to further curtail the use of human drug formulations on livestock.

In 2015, Taggart and colleagues in Spain also discovered the first documented case of a wild vulture in Europe being killed by exposure to flunixin, another veterinary NSAID; and presented the first evidence of wild vultures in Asia dying due to an NSAID other than diclofenac (this time, nimesulide). Working with colleagues in South Africa, Taggart also helped generate data from NSAID safety testing on captive birds, adding several other NSAIDs to a growing list of veterinary drugs that were potentially lethal to wild vultures globally.

In 2014, the European Medicine Agency drew on Taggart’s research in its report to the European Union on the risk posed to European vultures of diclofenac use in veterinary medicine in Europe. This report resulted in the EU asking all relevant member states to draw up national actions plans to reduce such risks. Taggart’s research has also fed into a major international ‘Multi-Species Action Plan’ aimed at conserving vultures globally, which was adopted by the United Nations Global Convention on Migratory Species in 2017. The monitoring of its impact is still ongoing.

Through SAVE, Taggart has supported capacity building in South Asia, for example, by working with colleagues in Germany and India to provide a lower-cost alternative test for diclofenac, using a simple ELISA (enzyme-linked immunosorbent assay) biochemical technique. Taggart has trained researchers to carry out NSAID testing and worked with multiple SAVE partners to ensure data gathered by NSAID monitoring and analysis in different countries is consistent and reliable, providing robust evidence for conservationists and government stakeholders.

UHI research into the impact of NSAIDs on vultures has been crucial in establishing a clear picture of evolving risks in South Asia and beyond. It has introduced robust new analytical techniques, shed light on new NSAID threats, and influenced new regulations to restrict or ban vulture-toxic medicines. It has informed drug safety guidelines and vulture recovery plans, all of which is underpinning conservation efforts that are now seeing positive early signs of vulture recovery in South Asian countries.

“The data provided by carcass surveys was absolutely critical to help drive legislative change”
– Dr Chris Bowden, RSPB

Research team

  • Dr Mark Taggart, Senior Research Fellow, UHI Environmental Research Institute 

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