Rhinos aren’t built for flight. Robin Radcliffe, a veterinarian at Cornell University with several decades of experience taking care of rhinos, is well aware of this. So when Namibia, one of the places where he works, decided to move critically endangered black rhinos (Diceros bicornis) hanging upside down from helicopters, he had one question: Is that OK?

Images of the brawny beasts, precariously poised at the precipice of extinction, swinging off helicopters grabbed eyeballs and boggled minds. The research also swept the Ig Nobel’s selection committee off its feet. Radcliffe’s team won this year in the “transportation” category. The satirical take on the prestigious Nobel prizes celebrates science at its quirky best. Or, as the organizers say, “achievements that make people laugh, then think.”

Turns out there’s a lot to think about.

Using helicopters to transport animals isn’t novel, but hanging them by their feet is. For decades, conservation organizations, especially in Africa, have resorted to translocation to repopulate “empty” parks with iconic species like rhinos, elephants and lions.

But the practice has a checkered record as a conservation tool. One paper describes it as a “high-cost endeavor with a history of failures.” The success of translocations in safeguarding the species and benefiting the ecosystems where animals are resettled depends on many factors, including animal behavior, proper monitoring, and community support. A lack of knowledge on many fronts bedevils even the most well-planned translocation operations.

Despite this, airlifting of everything from humble antelopes to mighty elephants continues in different parts of Africa. Transportation by road in crates is the norm, but for more complicated operations, NGOs and governments sometimes employ both methods. Between 2016 and 2017, African Parks moved more than 500 elephants into Malawi’s Nkhotakota Wildlife Reserve. As part of the move, cranes airlifted the elephants onto the back of trucks to begin a 500-kilometer (300-mile) cross-country haul.

While there’s talk of airlifting becoming standard practice for some animals in remote regions, the list of unknowns remains long. Radcliffe called Namibia’s operation a “leap of faith,” but praised the government for prioritizing the animal’s health. Mongabay spoke to the rhino expert to find out the story behind the eyeball-grabbing photos and why it’s important to study upside-down rhinos. Below are excerpts from the conversation, edited for length and clarity.

Mongabay: What is happening in this photo?

Robin Radcliffe: That’s a real shot of a rhino being airlifted under a helicopter. They were moving rhinos to a remote location in northwest Namibia by helicopter. The people on the ground, they’re getting ready for the rhino to land, and they have a mattress. They want to make sure the rhino has a comfortable landing. Rhinos are very rugged, but if the landing was not smooth, they don’t want the rhino to bump on the ground.

Mongabay: How did we get to airlifting rhinos upside down?

Robin Radcliffe: The traditional way to move a rhino is to immobilize it with drugs, partially wake it up and walk it into a crate. The crate is then loaded on a truck, and the animal is trucked across to its new destination, which could be hours or even days away.

The idea of airlifting rhinos was born out of necessity. Our team in Namibia was planning an operation to move rhinos into a very remote region of northwestern Namibia, where the rhino had been extirpated. It’s a very rugged part of Namibia; there are very few roads, so they decided to airlift them.

Namibia was not the first one to move rhinos under a helicopter. The South Africans did it first; they started in the 1990s. They were using a big net and metal frame. The problem with that method was that they had to ferry a lot of equipment. They had to bring in the metal frame, the net. It took a lot of people and the positioning of the rhino wasn’t ideal.

The Namibians were the first to do the slinging method. Actually, they did the translocation before we did our research.

Mongabay: Isn’t it a bit like putting the cart before the horse?

Robin Radcliffe: They took a leap of faith. In the best of both worlds, you would go ahead and do the research first and make sure everything was safe. This group from Namibia had a ton of experience. They already knew rhinos had been moved upside down. They just hadn’t been moved upside down, hanging by their feet.

A lot of things happen in Africa and never get studied. The fact that Namibia decided we should understand how it affects the rhino’s health showed a strong commitment by the government to make sure that the rhino’s health was a priority.

The value of moving a rhino upside down is that it is very quick. It eliminates a lot of the factors [linked] to the stress of moving them in a more traditional fashion.

Mongabay: Do you mean stress for the folks who are moving them or stress for the animals?

Robin Radcliffe: I think both. Some recent research has shown that rhinos that are translocated suffer some complications like changes to their body function. They can become dehydrated, they can have changes to their metabolic function. All of those things cause stress to the animal. So, the quicker you move a rhino, the safer it’s going to be.

The value of airlifting is you can do it quicker. You can also move them into areas that are otherwise not readily accessible.

Mongabay: For your study, you used cranes to simulate airlifting by helicopter?

Robin Radcliffe: Yes, there is a transport truck that has a crane. In a normal translocation, that crane is used to lift the crate on and off the truck, but we use the crane to simulate how a rhino would be hanging under a helicopter. We’re looking at how they breathe, their oxygenation, carbon dioxide [levels] and comparing it to data that we have on rhinos lying on their side.

Mongabay: What did you find?

Robin Radcliffe: We were surprised that a rhino hanging upside down was actually not any worse, maybe even a little bit better than a rhino laying on its side.

We know from our previous studies that rhinos that lay on their side are subject to something called “dead space.” Dead space is simply that part of every breath you take that does not contribute to gas exchange. If a rhino is on its side too long, it can have positional effects that increase the dead space.

We found that that rhinos hanging upside down actually have less positional effects associated with dead space and a little bit higher oxygen saturation. Those things were not statistically significant. Our sample size was pretty small. We only had 12 animals in our study.

Mongabay: It looks mighty uncomfortable for the rhinos. Is it?

Robin Radcliffe: As a wildlife veterinarian, it’s not like a human physician where you can ask your patient, “Hey, how are you feeling?” The rhino, when it’s moved upside down, is anesthetized. I don’t think the rhino really knows what position it’s in. If you look at the anatomy of the rhino, it has a very heavy, a very large neck and head. When you hang them upside down, the head hangs really low. That does two things: it straightens out the spine, and it also straightens out the airway. From a strictly anatomical perspective, it’s actually an ideal position for a rhino to be in.

One of the problems with hanging other animals upside down is that their spine curves and abdominal organs press into the diaphragm and impede breathing. We don’t think that’s happening in the rhino because the head and neck act as a counterbalance.

Mongabay: What about blood circulation?

Robin Radcliffe: There could be some pooling of blood in the head, for example, or other parts of the body, but we have not studied that.

Mongabay: Is there a timeframe after which this can become dangerous?

Robin Radcliffe: That’s an area of our future research. In our paper, we did 10 minutes, in the hanging position, maybe 20 minutes. In Namibia the rhinos have been moved for up to 30 minutes with no problems.

Mongabay: Did you replicate the height that helicopters go to?

Robin Radcliffe: We did not replicate that. Obviously, the higher you go, the less oxygen in the air. We were able to calculate what that difference was, but we didn’t test it.

Mongabay: Is transporting rhinos upside down by their feet just the most convenient?

Robin Radcliffe: I wouldn’t say convenient because that makes it sound like it’s easiest for the people. Yes, it is convenient, and, in many cases, it’s also safest and best for the rhino. But, it’s not like this is going to replace crate transportation.

The disadvantage of airlifting rhinos is that it’s expensive. It requires two helicopters — the darting of the rhino from a smaller helicopter, and then to airlift a rhino, you need a pretty big helicopter. A black rhino weighs about 2,000 to 2,500 pounds, so 1,000 kilos at least. White rhinos weigh even more.

Mongabay: Is this advisable for other large mammals? Has the safety aspect been studied for other animals?

Robin Radcliffe: They’re already using it for elephants, and it’s revolutionized how they move elephants. It is also used for other ungulates like the giant sable antelope. To my knowledge, nobody else has done studies on the aerial suspension of species in this manner.

Mongabay: Do you have a wish list for the kind of research you’d like to see done before translocating wildlife?

Robin Radcliffe: I think this is a luxury in many cases to be able to do very in-depth research on a specific question about rhino translocation. Wildlife veterinarians are working in a region of the world where they don’t have tons of resources. I’m impressed with my colleagues that work in Africa because they are so good at making the best-informed decisions without the best available research. More and more conservation organizations are working with partners that can offer support for research.

Citations:

Radcliffe, R. W., Jago, M., Morkel, P. V., Morkel, E., Du Preez, P., Beytell, P., … Gleed, R. D. (2021). The pulmonary and metabolic effects of suspension by the feet compared with lateral recumbency in immobilized black rhinoceroses (Diceros bicornis) captured by aerial darting. Journal of Wildlife Diseases, 57(2), 357-367. doi:10.7589/2019-08-202

Berger‐Tal, O., Blumstein, D. T., & Swaisgood, R. R. (2019). Conservation translocations: A review of common difficulties and promising directions. Animal Conservation, 23(2), 121-131. doi:10.1111/acv.12534

Banner image: Image courtesy of Namibian Ministry of the Environment, Forestry, and Tourism.