Next week, as part of the vulture conservation project LIFE Re-Vultures, we are hosting a two day international workshop on the impacts of veterinary drugs on vultures in Dadia, Greece.
Threat to vultures
Wildlife poisoning is the single biggest threat to vultures and other scavenger species across the world, but it is a complex issue. When wildlife poisoning is mentioned it is often the deliberate and illegal act of directly placing toxic products in the natural environment with the explicit aim of killing wildlife. Vultures are often unfortunate casualties of this act with the majority of cases of illegal wildlife poisoning dealing with conflicts with mammalian predators of livestock.
However, other forms of wildlife poisoning occurs which is completely unintentional, when vultures feed on the remains of livestock that have been treated with veterinary products.
The steep decline in vultures
At one point India’s Oriental White Backed Vulture was the most common bird of prey on the planet. However, over a 20 year period between the 1980s and early 2000s the population of this species and others in India and southeast Asia declined by between 95 and 99 percent. A study in 2003 found the main, and likely only cause, to be a Non Steroidal Anti Inflammatory Drugs (NSAID) veterinary drug, Diclofenac, used to treat cattle. The study revealed that the drug caused kidney failure in vultures, particularly of the genus Gyps, even if the birds consumed less than 1 percent of the animal remains that contained a lethal dose.
Since that study multiple studies have demonstrated the evidence that other veterinary products used on livestock such as antibiotics, antiparasitics and anthelmintics, euthanasia drugs, esp. barbiturates, represent a serious threat to the health of vultures and other scavenger species. All these veterinary products can cause acute or chronic intoxication, depending on the product and the level of exposure of the livestock.
Keeping Europe’s vultures safe
Despite the evidence that Diclofenac was likely the sole cause of the collapse of vulture populations in India, the drug is still marketed legally in Italy and Spain, home to 90 percent of Europe’s vulture populations. Other countries such as France have prohibited the drugs use, helping to protect vultures.
Across the whole of Europe, many farm animals receive doses of antibiotics and other veterinary drugs. With the change in sanitary regulations following the outbreak of BSE in the early 2000s feeding stations were set up to support vultures and other scavengers in times of food scarcity. However, the supply of animal carcasses at these feeding stations is increasingly coming from more industrial farming practices and as a result may contain more veterinary drugs, which may be a potential problem impacting on vultures, that needs to be monitored.
Veterinarians, researchers and even governmental authorities in countries that have vulture populations may be unaware that certain veterinary products can be toxic to wildlife. Whilst it is well known the impact of the anti-inflammatory drugs such as Diclofenac, the sub-lethal effects as a result of long term of exposure to remains treated with other drugs such as antibiotics may be less well known. In some cases, veterinary drugs can act similar as pesticides or heavy metals such as lead poisoning from the use of lead ammunition and as such needs to be taken into account when correctly investigating and monitoring poisoning incidents.
With the International Workshop on Vultures & Veterinary Drugs workshop hosted as part of the LIFE Re-Vultures conservation project, we aim to help raise awareness of this important issue.
Over the course of two days the Workshop we will bring international experts from this field from across Europe and staff from the different LIFE conservation projects working to implement activities on this subject with representatives from veterinary service in Bulgaria and Greece to share good practice and expertise. Through this work we hope to raise awareness and make the Balkans safer for vultures.
Starting in 2016, the five-year LIFE RE-Vultures project was developed by Rewilding Europe, in collaboration with the Rewilding Rhodopes Foundation the Bulgarian Society for the Protection of Birds, WWF Greece, the Hellenic Ornithological Society and us here at the Vulture Conservation Foundation. The aim of the project is to support the recovery and further expansion of the populations of Cinereous and Griffon Vultures in the cross-border region of the Rhodope Mountain by improving natural prey availability, monitoring movements of birds to help understand the threats they face and carrying out activities that will reduce the mortality of the populations from threats such as illegal wildlife poisoning and collisions with electricity infrastructure.