The humble bee. Is there anything it can’t do? They pollinate flowers, produce delicious honey and now, fresh from being voted the most important living being, they are being considered by the German police as potential drug detectors.

Detector Bees: Are they viable?

Four years ago, in 2015, researchers at the University of Cologne successfully trained honeybees to tell the difference between cocaine and heroin. They claimed that the insects could, one day, be used to replace sniffer dogs.

Then, just recently, 22-year-old beekeeper and police officer-in-training Sonja Kessler reignited interest in the idea with a bachelor's thesis for which she received a special prize from the European Police Congress. Entitled “Detector Bees – A Revolution for Police Work?” the thesis discusses the practicalities of using bees in drug and explosives detection, with the possibility of replacing police dogs with bees.

The aspiring police officer explains that through a reward method, whereby a certain smell is accompanied with a sugary reward, bees can be conditioned to recognise certain smells. Once conditioned - which only takes a few minutes - the bee extends its proboscis (a straw-like tongue), in anticipation of a sugary treat, whenever it detects the smell, thus alerting the police.

In her thesis, Kessler writes that the reward method can be used to condition whole colonies of bees. The insects could then “search an area of up to 50 square kilometres”. If covered with a fluorescent powder, they could be easily found by drones, even in large spaces. However, she does admit that this all depends on the time of day, weather and season.

Could the German police really use bees?

While the idea may at first sound a bit far-fetched, the German police union does recognise its potential. Trade union spokesperson Michael Zielasko said, “We shouldn’t laugh at the proposal,” as it seems like the police are taking it seriously. A viable alternative to tracking dogs, which are expensive to train and have a short working life, would be most welcome. Bees, on the other hand, cost very little to keep, can work longer hours, and are faster to train.

There are, however, some drawbacks to Kessler’s proposition. Firstly, it is still unclear how far a bee can detect a smell from; as all research has been conducted in close conditions, we are still not sure whether bees can smell from a distance. Legal problems could also potentially arise: what happens if a bee stings a subject? And will evidence from bees be considered admissible in court?

The idea has caused some debate amongst scientists: Dr. Peter Rosenkranz, head of the Baden-Württemberg State Institute for Bee Science at the University of Hoffenheim, thinks the idea is theoretically possible. Others, however, point to problems like the bee's short life span and the practicality of finding and collecting thousands of tiny insects once they have been deployed.

Despite this, Kessler hopes to see “service bee squads” supporting K9 units soon and is convinced that they can be a real asset to the police force.