The population size of the white-backed vulture has been decreasing significantly within the past few decades. In 1992, the population was estimated at 270,000. Over the past two decades, its population has noticeably decreased. BirdLife international estimated that over the past 40 years, the population of the white-backed vulture has decreased annually by a mean of 4.1%, culminating to an overall decline that lies between 63 and 89%, and such harrowing declines have also been recorded in the populations of its other African relatives. A recent study found that white-backed vultures have a high survival rate. Individual adults have the highest survival rate, while 2 year old birds have the lowest survival rate. Across all ages, the survival rate is estimated to be 90.7%. This means that the deaths of adult vultures will lead to rapid population declines. The loss of adults will cause less reproduction and with younger birds less likely to survive, the population will drop drastically. A major cause of population decrease is the loss of habitat and anthropogenic disturbance. Fires have also caused the destruction of trees used for nesting habitat. Humans also have a large impact. Power lines have caused many vultures to be electrocuted. In Kenya especially, humans are using a toxic pesticide called Furadan, which has led to many vulture deaths. Vultures are also being poisoned by humans, although not intentionally. In order to kill hyenas, lions, and other predators, herders add poisons into their livestock. Vultures ingest the poison upon eating a deceased animal's carcass. This poisoning generally occurs outside of protected areas but is a leading factor in the population's decline. Habitats are also being disturbed by human land management and direct nesting persecution patterns.
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