Threats to Birds of Prey

Contaminants

Birds of prey are excellent indicators of environmental health. Their problems are an early warning system that there may be effects on people, too.

In 1962, Rachel Carson wrote her seminal book, “Silent Spring,” which alerted the world to the environmental dangers of DDT. Eventually, the use of the pesticide (dichlorodiphenyltrichloroethane) was banned in the United States and other countries. After nearly 30 years of captive breeding and releases to the wild, in 1999 the Peregrine Falcon was considered fully recovered from its brush with extinction due to DDT and was removed from the U.S. Endangered Species List.

Since then, many other substances have been found to have unintended consequences for birds of prey and other wildlife, especially scavengers at the top of the food web.

An Oriental White-backed Vulture perches atop a palace in India

Munir Virani

The Peregrine Fund discovered in 2003 that the veterinary drug diclofenac was responsible for a catastrophic collapse of vulture populations in South Asia in less than a decade. The drug was banned for veterinary use in 2006 by India, Pakistan and Nepal, and Bangladesh took similar action in 2010. Continued use imperils efforts to recover the species affected.

The drug is still used to treat livestock in some areas although a safer alternative, Meloxicam, is now available. Vulture populations may be stabilizing, but, tragically, some species already have declined by up to 99 percent, making extinction a continued threat to these ecologically and culturally important birds.

Species affected include:

Long-billed Vulture
White-rumped Vulture
Slender-billed Vulture

Different bottles of Diclofenac are lined up

Diclofenac is an anti-inflammatory drug used to treat ailing livestock. Even a trace of diclofenac in a carcass is enough to cause vultures to die slowly and painfully of renal failure. Just one cow carcass can poison many vultures, which eat in social groups. Not only has diclofenac brought the birds to the brink of extinction, but the effect of the vulture population decline on people is becoming evident, too. The drop has caused a burgeoning population of feral dogs, rats, and other animals more likely to come into contact with humans and spread rabies and other diseases.

Vultures fill a vital ecological niche as nature’s clean-up crew. These remarkable birds can pick a carcass clean long before it has time to contaminate land and water resources.

The Peregrine Fund was the first conservation organization to set up “vulture restaurants” in South Asia, where diclofenac-free carcasses were set out for vultures to eat.

A Critically Endangered White-backed Vulture is dead on the ground after a poisoning incident

Munir Virani

In Africa, we have been collaborating and working hard to stop the scourge of retaliatory wildlife poisoning in southern Kenya that has devastated populations of critically endangered vultures and other scavengers. Retaliatory poisoning usually occurs when predators such as lions, hyenas, and leopards attack livestock. Without compensation in place, livestock farmers resort to lacing their dead livestock with easily accessible agro-chemicals with the intention to kill predators. Vultures that scavenge in large numbers on dead animals often succumb to the poison and hundreds can die as a result.

Munir Virani

Two of the most substantial poisoning threats come from poachers and traditional healers. Poachers deliberately poison vultures in an effort to eliminate them because by flying over carcasses vultures reveal the poachers’ presence. Vulture body parts are harvested unsustainably for medicinal and other belief-based uses and this is typically carried out using poisons.

Munir Virani

In 2015, a study completed by an international team of researchers, including leading scientists from The Peregrine Fund, estimated rates of decline (over three generations) for the following eight vulture species: Bearded Vulture Gypaetus barbatus (-70%), Egyptian Vulture Neophron percnopterus (-92%), White-backed Vulture Gyps africanus (-90%), Rüppell’s Vulture Gyps rueppellii (-97%), Cape Vulture Gyps coprotheres (-92%), Hooded Vulture Necrosyrtes monachus (-83%), Lappet-faced Vulture Torgos tracheliotos (-80%), White-headed Vulture Trigonoceps occipitalis (-96%).

This study led to Egyptian, Lappet-faced, and Cape Vultures being listed as Endangered and Hooded, Rüppell's, White-backed, and White-headed Vultures being listed as Critically Endangered. It also raised international awareness about the vulture crisis in Africa.

Over the last three years, our project has made significant strides towards better protecting vultures in Kenya, and has helped establish a framework that can be applied to other parts of Africa where poisoning is decimating vulture populations. We have built trust and made an important impact within local communities, instilling a sense of ownership and responsibility about vultures, other wildlife, and the inappropriate use of poisons. Equally, the capacity for communities to actively engage in vulture conservation activities has increased significantly thanks to the work of project partners, and parallel to this, so has the interest and willingness of communities to protect vultures and their wider environment.

As part of our major achievements, five Vulture Liaison Officers (VLOs) plus ten Vulture Scouts were fully trained to collect intelligence on potential poisoning activities as well as conduct outreach, poisoning intervention training, mitigation and conservation activities. We are also proud to state that the “Vulture Protector Network”, a WhatsApp communication group, has been expanded and currently has 52 participants from 22 different conservation organizations that share information on livestock predation and poisoning incidents related to human-wildlife conflict. Based on our networks, we achieved successful and effective response to and decontamination of numerous poisoning incidents – these included two in the Masai Mara that killed 40 and 20 vultures respectively; and the other just south of Nairobi National Park that killed five vultures. Without Rapid Response Training and the Vulture Protection Network, 200 or more birds would have probably died. Whilst improved vulture survival rates of tracked vultures during the past 10 years may not necessarily be a direct function of our conservation efforts, it gives hope and is reassuring for the future survival of vultures in Kenya.

We can unequivocally state that every single wildlife mortality in southern Kenya (poisoned or not) is documented primarily as a direct result of the expanding Vulture Protection Network. These grassroots impacts are critical for the longevity of vulture conservation in Africa, and along with the support of higher-level initiatives such as the Wildlife Poisoning Response Protocol, we are confident that the project has helped set a precedent for vulture conservation across Africa.

As a result of a fast-growing network of trained teams on the ground, managing wildlife poisoning continued to improve, which saves vultures’ lives. However, there is need to expand this work to cover other critical areas, especially in northern Tanzania, where nearly all of the GPS-tagged vultures utilize and where poisoning incidents occur but are unreported.