Photo by Munir Virani, courtesy of The Peregrine Fund

The USGS National Wildlife Health Center (NWHC) is collaborating on investigations into the cause for decline of the white-backed vulture in Pakistan.  Most of these vultures have died from kidney failure.  Residue analysis in wild vultures from Pakistan and toxicity experiments have shown vultures, unlike mammals, to be extremely sensitive to diclofenac, a non-steroidal anti-inflammatory drug, commonly used by veterinarians on agricultural animals in Pakistan.  Small concentrations of this pharmaceutical remaining in tissue of livestock scavenged by vultures results in renal failure. These findings implicate diclofenac as the cause of drastic decline in the white-backed vulture population (90%) in the past 5 years.  Vultures are exposed to diclofenac by scavenging agricultural animals that have been treated with diclofenac before death.  The journal Nature has published the paper reporting these findings.