From time to time, alerts about wild animals that enter natural environments and attack cattle or hikers appear in some media. Those same media usually point to the wolf as the person responsible for such messes.
After the wolf, the animal with the worst fame among these sectors of society is the vulture. In Spain we have four species of vultures: the bearded vulture ( Gypaetus barbatus ), the Egyptian vulture ( Neophron percnopterus ), the black vulture ( Aegypius monachus ) and the griffon vulture ( Gyps fulvus ), and they tend to grab headlines and viral videos.
To answer some questions about vultures and find out whether or not this bad reputation is well deserved, I interviewed Eneko Arrondo , a doctor in biology from the Miguel Hernández University, and a specialist in the ecology and biology of scavengers.
The feeding habits of the vulture
Q. It is often said that vultures, and especially black and griffon vultures, are animals exclusively, or almost exclusively, scavengers. It’s true?
R. _ Yes, the diet of vultures in general and of Iberian vultures in particular, is entirely a scavenger. Only in exceptional cases do they prey on dying or very weakened animals. We could say that the majority of individual vultures never eat live prey and that, if they do, that prey was not fully functional.
Q. Vultures form large flocks, and often circle, either because they have caught a thermal current and are gliding, taking effortless height, or trying to locate a food source. The sight of several dozen vultures flying in circles can impress people. Is it dangerous to be near this type of flock?
A. No. There are no records of vulture attacks on humans. Only a few very rare interactions are known in which someone has tried to manipulate a vulture and it has defended itself. These situations are usually presented by the press as “attacks” but strictly speaking they are not, since they do not imply an intentional and unjustified aggression of the animal on the person. Rather, they are logical accidents within human-wildlife relationships.
The vulture’s relationship with cattle
Q. The relationship between the vulture and cattle has always been symbiotic. Generally, the ranchers abandoned the dead animals and the vultures, in their role as scavengers, tracked them down and consumed them. However, in many places, these animals were moved to middens, specific areas that served as feeding grounds for vultures. Is it possible that these middens have somehow changed the behavior of the vultures?
R. The middens have existed since the Neolithic, when human beings began to become livestock and sedentary. There are even “dunghills” where the carrion that is thrown are human corpses as it happens in the towers of silence of the Zoroastrian culture or the Tibetan sky burials. The middens are very predictable food sources both in space and in time, which is why, without a doubt, they have modified the behavior of the vultures in this time.
However, these behavioral adaptations do not imply a greater risk of attacks on live cattle, but rather the opposite, since by providing food on a regular basis to the vultures, the chances that they look desperate enough to attack are reduced. a living animal no matter how weak it is. In any case, the role of middens in the ecology and conservation of vultures is very complex and is worth an article by itself.
P. I note for a future article on the subject, Eneko. Following this thread, there are those who maintain that, as a result of the fact that during the ‘mad cow’ crisis the abandonment of livestock carcasses was prohibited for a certain time, the vultures, moved by hunger and uninhibited by the fear of humans , changed their behavior, becoming predators that attack livestock: sheep, cows and even horses. There have even been videos of attacks on cows in labor and testimonies from people who claim that a vulture tried to eat them. How much truth is there and how much hoax in this?
R. As I have said before, what are supposed to be attacks on people are actually misinterpretations of defensive behavior by vultures. They do not pose a greater risk to humans than any other wild bird that, when trying to manipulate it, defends itself by biting us.
As for attacks on calves giving birth, it is something that has happened historically, since cattle births, unlike what happens in wild ungulates, are slow and difficult because we have selected the animals so that they have the largest offspring. possible to serve us as food. But even though there have always been attacks, they have never been widespread. In fact, today it affects less than 0.5% of the livestock herd. That is to say, they are anecdotal events that, due to their impressiveness and the viral transmission of social networks, are magnified far above their real effect. In this sense, some works in different parts of the world point out that what has happened is a change in the perception of ranchers due to the fact that the modernization of the sector makes them spend less time with the herds and what they previously saw as something “normal” now seems strange and dangerous to them.
The role of the vulture in the ecosystem
P. Apart from the bad reputation, the truth is that vultures play, like all species, a certain role in ecosystems. To what extent is that role important? What are the services provided by vultures in ecosystems?
A. Vultures accelerate the decomposition of dead matter to levels that make them key pieces of ecosystems. For example, in those places where the vultures disappear, the carrion they do not consume is taken advantage of by mesopredators, increasing the risk of proliferation of diseases such as plague or rabies. From a purely human point of view, they represent the saving of thousands of euros and tons of CO ₂ when it comes to destroying the carrion of our cattle that, if there were no vultures, must be incinerated.
These services mean that although sensationalism sells vultures as dangerous and conflictive species, when it comes to truth, in many regions local farmers consider them to be beneficial species that help them get rid of the biological waste they generate.
In this matter, as is usual, sensationalism can take precedence over reason and scientific knowledge. However, it is important that the information that is disseminated be rigorous and based on the strongest scientific knowledge. For this reason, I thank Eneko Arrondo for the time granted for this interview and his abundant knowledge on the subject.
Ballejo, F. et al. 2020. The conflict between scavenging birds and farmers: Field observations do not support people’s perceptions. Biological Conservation, 248, 108627. DOI: 10.1016/j.biocon.2020.108627
Duriez, O. et al. 2019. Vultures attacking livestock: a problem of vulture behavioural change or farmers’ perception? Bird Conservation International, 29(03), 437-453. DOI: 10.1017/S0959270918000345
Lambertucci, S. A. et al. 2021. Presumed killers? Vultures, stakeholders, misperceptions, and fake news. Conservation Science and Practice, 3(6). DOI: 10.1111/csp2.415
Margalida, A. et al. 2014. Vultures vs livestock: conservation relationships in an emerging conflict between humans and wildlife. Oryx, 48(2), 172-176. DOI: 10.1017/S0030605312000889
Margalida, A. et al. 2020. Fake news and vultures. Nature Sustainability, 3(7), 492-493. DOI: 10.1038/s41893-020-0534-5
Oliva-Vidal, P. et al. 2022. Griffon vultures, livestock and farmers: Unraveling a complex socio-economic ecological conflict from a conservation perspective. Biological Conservation, 272, 109664. DOI: 10.1016/j.biocon.2022.109664