Taking care of carrion
Primary Source: Santangeli, A. et al. (2019). Priority areas for conservation of Old World vultures. Conservation Biology, 33(5), 1056–1065. https://doi.org/10.1111/cobi.13282
Featured Image: Mandyjj543, flickr.com
Serving a seemingly unpleasant, but noble role
As a kid, I was first introduced to vultures through characters in the Jungle Book. Even though these cartoon vultures were kind of goofy, they were depicted against a gray, lifeless background. This seems to be a common theme in children’s movies: vultures typically symbolize death and foreboding.
Vultures are associated with death because they consume dead animals. This may not be a pleasant role from our point of view, but it is an incredibly important one for ecosystem functioning. Vultures may aid in nutrient cycling, control the spread of disease by consuming the dead flesh that harbors it, and even reduce greenhouse gas emissions by consuming carcasses that would otherwise be incinerated. They don’t harm humans, unlike some other species that fulfill the same role (think rabid feral dogs!)
Scary-looking birds under siege
Vultures have a tough appearance, but they face a number of threats from humans. In order to provide suggestions on how to protect these death-eating birds, researchers analyzed geographic areas to determine where vulture populations overlap with known threats.
Farmers may use poison to kill carnivores that attack their livestock. When vultures consume these deceased carnivores, they are indirectly poisoned as well. The study measured the likelihood of this threat by quantifying the presence of livestock over a geographic area.
Some poachers poison vultures intentionally because the birds may inadvertently alert authorities to an illegal kill when they circle over an area. In order to quantify this threat, researchers measured the occurrence of species that are targeted by poachers.
Vultures can be harmed by collisions with wind turbines, so the researchers used a map established by a previous study of planned and installed wind power turbines to quantify collision risk. They also used a human influence index, established by a previous study, to quantify human population pressure, land use, infrastructure, and accessibility.
Spatial areas were identified where the greatest threats correlated with vulture populations. These spaces are priority conservation areas. The researchers also identified the governing bodies of these areas to identify potential stakeholders and managing bodies.
Bringing it all together
These analyses resulted in the first holistic map for vulture conservation across Eurasia and Africa. This map showed that priority areas were clustered within specific countries within southern and eastern Africa, southern Europe, the Arabian Peninsula, and the Indian subcontinent. This means that there is a disproportionate burden on some areas, but also presents an opportunity because there are fewer countries and stakeholders that need to coordinate with one another.
Focusing on these priority conservation areas is a great first step for protecting vultures, but won’t be enough for species that inhabit wider areas.
Researchers found that the nations where priority areas were located had well-functioning governing systems, which is a good sign. They also found that these nations tended to spend higher amounts of money combatting rabies. This may be because of a lack of vultures: the birds can help limit the spread of diseases and fulfill a role that could otherwise be taken over by rabies-carrying scavengers, such as wild dogs. There may be an opportunity here for nations to address vulture conservation and public health issues through shared legislation. Before these steps can be taken, there is a need for further research on the potential link between vultures and mitigation of disease spread.