AI meets animal intelligence: Vultures as health police
In large parts of Africa, vultures are threatened. Researchers want to protect them - and use them as health police at the same time. A feature written for young readers
Ruben Portas stalks deeper and deeper into the African bush. The GPS device in his hand shows him the way. It is still 100 metres, 50 metres, ten. Then Ruben suddenly stops. "This must be where it was, this is where the vultures were," he says. Surrounded by dense thorn bushes, he sees nothing at first. It has rained a lot in Namibia in the last few days. Also in Ruben's research area, the Etosha National Park in the north of the country. "The water makes it difficult for us," he says. "It washes away all the evidence."
Every day, Ruben is out in Namibia looking for clues. The scientist works for the Leibniz Institute for Zoo and Wildlife Research in Berlin. His goal: to learn more about the vultures' behaviour. Especially when, where and what the birds of prey eat. Since the start of the project in May 2022, he and his team have equipped 27 vultures with GPS sensors for this purpose. Ruben points to an app on his smartphone. On a map, he can see exactly how the vultures are moving and where they have spent a particularly long time. "Clusters" is what Ruben calls these points. They are shown in red on his map.
What is special about the technology is that the researchers have equipped it with artificial intelligence. In addition to the movement patterns, it also provides Ruben with a direct assessment of what the vulture has done. Ruben examines up to 20 red dots a day to confirm the data. But the artificial intelligence is not always right. Then the researcher has to correct the data. In the case of the cluster in the thicket, the AI reported a "medium-sized carcass". This means that the vulture has found and eaten dead animals there. "Probability: 80 per cent."
A few metres from the indicated spot, Ruben now kneels on the ground. He points to a small pile of dry grass and lets some of it trickle through his hands. "The undigested stomach contents of the
animals are usually the first thing we find," he explains. With a stick, Ruben strokes through the pile. A feather is hidden in it. And a few black and white hairs. As Ruben finds a bone nearby, he is sure: the AI was right this time. "These are the remains of a zebra." Ruben enters the data into his device, then photographs the surroundings. For the picture, he stretches his arms upwards and points the camera lenses downwards. Ruben wants to view the scene from the perspective of a vulture. For in future, the researcher and his team want to use the birds specifically as health police.
Vultures fly over huge areas in search of dead animals. Within a short time, they dispose of the carcasses of dead animals. This makes vultures important helpers for the entire ecosystem. Together with the carcasses, they also remove harmful pathogens from the environment. So we humans also benefit from the vultures' clean-up work: It prevents diseases from spreading.
Ruben and his team want to use the bird's eye view to develop an early warning system. One example: if the vultures find a conspicuously large number of animal carcasses in an area within a short time, this could indicate a disease outbreak. The system can then send a warning to the rangers in the park. "If we combine the vultures' intelligence with AI, we can keep a much better eye on developments in nature," says Ruben. But the researchers don't just want to use the vultures as health police. They also want to protect them.
Vultures are among the most endangered bird groups in the world. Fourteen of the 23 vulture species are now threatened with extinction. This includes the white-backed vulture, which Ruben is researching in Etosha National Park. In recent years, the species' population has shrunk rapidly. Some researchers estimate a decline of more than 90 percent. Today, it is estimated that about 40,000 white-backed vultures still live in southern Africa, a quarter of them in Namibia. One of the biggest threats to the vultures is poisoned animal carcasses. In South Africa, a neighbouring country to Namibia, for example, more than 100 vultures died in one sweep last year. They had all eaten a poisoned buffalo. In addition, there are other dangers such as power lines or medicine men who use the birds' heads as a traditional remedy. All of this worries Ruben. "When one species goes extinct like the vultures, the whole ecosystem goes out of balance.”
With the transmitters, the researchers can at least observe a few vultures. However, they can fly away at any time, far away from protected areas like the Etosha National Park. "That makes it difficult to protect the species," says Ruben. One of their vultures, for example, is now on the move in neighbouring South Africa. On Ruben's map, it appears as a lonely dot, hundreds of kilometres away from the others. They can't equip every vulture with transmitters anyway, the researcher says. "That would be far too expensive, unfortunately”.
Ruben steers his off-road vehicle to the next cluster. Like last time, his data predicts a medium-sized animal carcass. Ruben gets out of the car, shoulders his backpack and walks determinedly through the bush. But no matter how long he searches, this time he finds no clues. Until his eyes fall on a bony branch. He shakes it vigorously, nods and enters new data into his device. "The vulture wasn't eating, it was resting on the branch and bobbing a bit," Ruben explains. The artificial intelligence has mistaken the movement pattern for a feeding vulture. Data like this is particularly valuable for the team. "They help us improve the system." AI cannot replace the trained researcher's eye, at least not yet.
On the way back to camp, Ruben sees them in action, the vultures. About ten of them are circling in the distance. At the roadside, another vulture sits on a tree and spreads its huge wings. He looks a bit like a priest giving his blessing to the congregation. "This guy must have just had a shower," Ruben explains. "Now he's letting the wind blow him dry." And then the vulture soars high into the air again and flies away. The health police are on duty around the clock.
Read more: The feature was published in Zeit Leo, the children’s page of the German newspaper Die Zeit. Click here to read the full article (German).
Pictures: Tara Mette
