As toxic as diclofenac is to vultures and other species of raptors, it was surprising to discover that five countries in the European Union have authorized the use of the drug on domestic animals, with the oldest dating back to 1993.
According to experts in SEO/BirdLife (BirdLife in Spain), RSPB (BirdLife UK) and the Vulture Conservation Foundation, this is setting the stage for a mass die-off of endangered and ecologically valuable wildlife in Europe, reported BirdLife International
Rhys Green, a conservation scientist at the University of Cambridge, UK, and his colleagues suggests that the drug diclofenac could cause populations of Spain's Eurasian griffon vultures (Gyps fulvus) to decline by between 1–8 percent each year. Green and his colleagues published their findings
in the Journal of Applied Ecology.
Green is going up against the European parliament with his request. Spain is saying they have researched the vulture deaths and put them at between 15 and 39 deaths a year. Green's team has calculated a more worrisome number of deaths. They say it is more like 715 to 6,389 bird deaths per year.
One study here and one study there is not going to sway the powers that be, though. In a decision published on August 24, 2015, Mr. Andriukaitis on behalf of the Commission
"It should be noted that there has been no evidence of vulture poisoning linked to diclofenac in the EU since its first authorization. Strict rules on the disposal of fallen stock are provided for by the animal by-products legislation and apply to carcasses used in feeding stations for necrophagous birds."
Vulture declines in India, Pakistan and Nepal
From 1994 to 2004, a detailed study found that three vulture species on the Indian sub-continent suffered a 95 percent decline, all due to being poisoned by the veterinary use of the drug, diclofenac.
"This discovery is significant in that it is the first known case of a pharmaceutical causing major ecological damage over a huge geographic area and threatening three species with extinction," the US researcher from Washington State University said, according to the BBC in 2004
The Oriental white-backed vulture (Gyps bengalensis
), the long-billed vulture (Gyps indicus
) and the slender-billed vulture (Gyps tenuirostris
) are all now considered critically endangered. In India, the drug was phased out for use as a veterinary drug and was replaced by a much safer medicine, Meloxicam.
Since that time, diclofenac has been found to be toxic to the steppe eagles of Europe and Central Asia, as well as freshwater fish species such as the rainbow trout,
among others. Needless to say, the decline in vultures in India has led to an increase in the number of feral dogs, and as a consequence, rabies.
The study, "Potential threat to Eurasian griffon vultures in Spain from veterinary use of the drug diclofenac
," was published in the online Journal of Applied Ecology
April 25, 2016.