First recorded fatality from lead poisoning for Griffon Vulture in Bulgaria

The recent mortality of the Griffon Vulture is the first recorded death caused by lead poisoning for the species in Bulgaria. Tests showed old lead ammunition inside the vulture’s body and proved positive for lead poisoning as there was increased lead concentration in the blood.

The anti-poison dog unit in action.
Image: BSPB

According to experts from the Bulgarian Society for the protection of Birds (BSPB),  the first to report the case, the incident reaffirms that lead poisoning poses a severe threat to many vulture populations not only on the Balkans but throughout Europe. This case also reiterates that poaching is still a serious problem.

At the end of April, a mature Griffon Vulture marked with a GPS transmitter was discovered dead in the area of Studen Kladenets Reservoir in the Eastern Rhodopes. Now it’s confirmed that lead poisoning killed the vulture, which is an overlooked threat. The found bird was an adult female with reduced breeding performance for the last 3 years.  At that time, the increased concentration of lead in the bird’s blood and her behaviour raised doubts about chronic lead poisoning that were later confirmed. “Proving such cases is extremely difficult as lead contamination could remain undiagnosed. Often as a result of poisoning, birds may suffer strange their behaviour that may increase the likelihood of collisions with power lines, development of bacterial infection due to deteriorated immune system, etc., which mask the root cause,” commented Volen Arkumarev of BSPB.

The X-rays clearly showed identified ammunition in the vulture’s wing.

The body was transported to the Green Balkans Wildlife Rescue Center in Stara Zagora, where the experts performed an autopsy and detected changes in the bird’s liver. An X-ray enabled the cleared identification of bullets in the vulture’s wing. As a result, a Bulgarian laboratory conducted a very detailed analysis estimating the amount of lead accumulated in the liver and the bones, which are the primary depots for heavy metals. “As a result of the autopsy, X-rays and laboratory analysis we can say without any doubts that the vultures suffered from chronic lead poisoning, which probably originates from the lead bullets in the wing, “Arkumarev adds further. According to the experts, the origin of the lead bullets cannot be accurately identified, but it is clear that the bird was shot a long time ago but recovered from the trauma. There are many possibilities – the vulture may have been shot during her youth wanderings or migration in the Middle East, Turkey or later on somewhere in the Balkans. In several countries, and especially in the Middle East, poaching remains a huge problem and many organizations are dealing with the issue, and in recent years the governments of Lebanon, Egypt and Jordan have taken decisive steps to resolve these problems.

Another serious threat and source for lead-poisoning is the exposure to lead, primarily through the ingestion of lead ammunition. In USA the lead poisoning was the main cause for the decline in the condor populations that were brought on the brink of extinction. In these areas of America, mostly lead-free spirits are currently being used, but in Europe, unfortunately, this practice is still not that popular. In some areas with bearded vultures in France, there is also a significant breakthrough lead-free ammunition well received by hunters. However, in countries like Austria, Italy, the problem is still very serious.

The threat of lead poisoning and the negative impact that this may have on vultures. To reduce that threat the team is currently within LIFE Vultures project the team is working to reduce the use of lead ammunition by promoting promote lead-free hunting practices.

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