VULTURES
Vultures are fascinating creatures. They are absolutely crucial for the functioning of ecosystems yet, due to a combination of human driven threats, they are in trouble. With populations declining across the guild we are currently facing potential losses of many vulture species. This would not only be disastrous for biodiversity, but for both human health and economies too.
Vultures are scavengers. This means that they feed on carcasses and dead matter. They both compete with and complement other species which partake in scavenging behaviour such as hyenas. Each vulture species has a particular role and feeding behaviour which ensures that an entire carcass can be cleaned up very quickly. Some might just see this feeding behaviour, saprotrophic nutrition, as a means of survival. But it is a major ecosystem service, aka a thing that would cost us a ton of money and require significant innovation to recreate. Vultures remove dead matter and in turn reduce the spread of disease. Can you imagine how much it would cost us to remove all the carcasses left around the bush so they didn’t pollute water courses? Vultures do all of this for us…for free.
“VULTURES ARE SUPREMELY ADAPTED TO SCAVENGING BUT THEREFORE [ARE] EQUALLY VULNERABLE TO THREATS TIED TO THIS BEHAVIOUR”.
Safford et al., 2019.
indirect Poisoning
Despite their crucial role, vulture populations are declining at alarming rates. This is for a number of reasons, all of which come under the banner of human wildlife conflict. As we have seen with African wild dogs, generally, humans and wildlife don’t get on. Sat comfortably in our living rooms reading this we may wonder why anyone would want to persecute an animal. But if you’re trying to grow enough crops to feed your family or rear enough livestock to make a bit of money then the wild species which graze on your crops or predate on your livestock are vermin which need to be removed. Megafauna, such as elephants and lions, are most often the victim of persecution as a result of predation or grazing or simply due to the threat they pose. There are many methods of killing an animal utilised in these situations, one of which is poisoning. However, in the bushveld, when one animal is poisoned, many more die. Vultures, in their role of scavengers, feed on the carcasses of poisoned animals and also succumb to the poison. As many of us will have seen, it is very rare to find just one vulture on a carcass. Vultures tend to flock to a feeding site and thus many 10s could be poisoned from one carcass.
direct poisoning
Accidental poisoning of vultures isn’t the only threat to these species. Sometimes the poisoning is on purpose. In order for a vulture to find a carcass, they need to fly. We all have heard the stories of, or seen, vultures circling and this image has developed somewhat of a macabre notion. But this is simply an animal searching for food. Whenever we’re in the bush and see vultures that are descending we drive in that direction, because chances are that wherever the vultures are there is going to be something good to watch. But vultures don’t discriminate between an animal which has died of natural causes and one which has died at the hands of a human. This means that vultures can very often and very quickly give away the location of a carcass of a poached animal. This sentinel role that vultures play has led to a spate of carcass poisoning, so that in the case of future poaching there will be fewer vultures present to highlight the nefarious activity.
belief based poisoning
The poisoning of vultures is not always a knock on effect or an effort to remove a tell tale sign of criminal activity. Vultures are in demand by the traditional medicine market across Africa (also known as the ‘muthi trade’ in South Africa) and animal carcasses are often poisoned with the direct aim of collecting dead vultures for their body parts. Much like pangolin scales and lion bones, there is no proven medicinal benefit of using or possessing animal body parts. However, the capabilities which vultures have evolved and the niche which they adopt has led to the development of a lot of cultural myths and legends related to them. Vultures have incredible eye sight….8 times that of human 20/20 vision. Their ability to spot a carcass 4km away has created a belief system that suggests vultures can see into the future. This belief system goes further to consider that should a human posses a vulture body part they will also gain these psychic abilities. Of course, there is no scientific evidence to back this up. This is a cultural belief. Unfortunately, as we discussed with pangolins, changing culture will take generations, but progress is being made and it is extremely important that this momentum is continued.
“TRADE IN TRADITIONAL MEDICINE IS CONSIDERED THE SECOND LARGEST THREAT FOR AFRICAN VULTURES, ACCOUNTING FOR 29% OF THE DEAD VULTURES RECORDS BETWEEN 1972 AND 2014”
Mateo-Tomás & López-Bao, 2020
Power line collisions
Believe it or not, there are even more threats which vultures are facing. This next one is a less direct threat posed by humans, but still a conflict and still one which is having a negative effect on vulture populations. The development of power lines across countries and alarmingly close to vulture roosting sites is of great concern. Vultures, alongside many large and charismatic avian species, such as the blue crane, are commonly electrocuted following collision with power lines. This is an extremely difficult issue to overcome, because humans need electricity, no doubt about that. But such a demand for it is affecting multiple species. Therefore careful planning of future power line development is paramount to ensure that the least collisions possible occur.
vulture conservation
All of these threats have started to show their effects. In the last 3 decades, the populations of 7 African vulture species have declined by 80% or more. Vultures themselves hold a value simply for existing. But as I have mentioned before and as we discussed on our podcast, the value of biodiversity simply for existing (aka its intrinsic value) sadly isn’t enough. Humans work on economic terms and need to justify conservation through returns on investment. Vultures do attract some tourists. But if we look at it from a different angle, in terms of cost saved, the argument for conserving vultures is extremely strong. To date, the monetary amount of free service that vultures provide us is not known. But it’s safe to say that without them there would be many more carcasses lying around the bush and the whole ecosystem cycle would be slowed down. Without vultures, nutrients would not get returned to environments and disease would very likely be a lot more prevalent. Again, this demonstrates that the loss of one species, or a guild, can have negative impacts on whole ecosystems. Therefore it is essential that when we approach conservation and tourism we do so with an ecosystem approach, which looks holistically at the entire system rather than favouring individuals species.
Conserving vultures is essential. But, much like the lion bone trade, fixing the problem of vulture population decline requires massive political, socio-economic and cultural shifts. It will require educational and generational change, it will require policy changes and harsher punishments for poisoning and it will require logistical and research inputs to ensure that vulture deaths as a result of conflict with carnivores are less common. Protected areas are extremely valuable and harbour many threatened species, including vultures. But, as with African wild dogs, vultures range really far and could easily come across a poisoned carcass or a power line. So when you next go to the bush, take a moment to stop and admire the vulture that you might see sitting in a tree or, if you’re lucky, observe their incredible social behaviours on a carcass. They are absolutely spectacular creatures and deserve to be viewed by all in this light.