Hanging around: Ig Nobel Awarded for Rhino Transport Discovery

An experiment to observe upside down rhinos has won an Ig Nobel prize. The Ig Nobels were introduced in 1991 for the purpose of awarding trivial or humorous advances in the field of science. A US publication known as The Annals of Improbable Research organises them. While these Ig Nobels are not as renowned as an actual Nobel Prizes, they still highlight some pretty cool advancements in science!

Namibia, Africa is home to 1/3 of the world’s 5,500 black rhinos. Conservationists have to tactically relocate the animals in order to preserve local populations and encourage genetic diversity. Many rhinos are moved to national parks, free from poachers who hunt them down for their horns. Others are moved to conservancies: community preserves that attract visitors and tourists, increasing revenue by promising rhino sightings. 

Transporting animals that weigh over 1 tonne can be an extremely difficult task.  Furthermore, Namibia’s rough terrain, of savannah to sand dunes means it’s unrealistic to move them via streets. 

Helicopters have been used for the transportation of rhinos, they are sedated and flown hanging upside down. However, little was known about the clinical risks of this method.

Robin Radcliffe and colleagues conducted a study to understand If the rhino’s health would be affected by being suspended by their legs below a helicopter. Potent opioids have side effects that include reduced oxygen in the blood, higher metabolism, and respiratory depression. Therefore, the side effects of tranquilisers on the health of these animals was taken into consideration. Twelve were suspended rhinos from a crane and their physical responses measured. Results showed that being dangled upside down was the least unsafe position for them. 

Physiological effects were roughly the same as when the rhinos were upright, and the animal’s developed hypoxia. However, both oxygen levels and measures of ventilation were higher when the animals were upside down. Unexpectedly, ventilation was improved through suspension rather than when the rhinos were lying chest down or on their sides. This may have been due to the high level of blood flow through the lower part of the lung, however there was a lack of perfusion of the upper part of the lung due to gravity. Therefore, when a rhino is hanging upside down, it is essentially like its standing up- there is equal perfusion of the lung. 

This research changed rhino translocation as well as elephant translocation. Moving these animals by their feet is now recognised and accepted. It has now encouraged the idea of conducting similar research on other species including hippopotamuses and buffalos.