Bees behave like criminals and could help catch them

New research using bumblebees to refine and test a technique used to catch serial killers has implications for wildlife conservation, fighting malaria and combatting bioterrorism.

Writing in the Journal of the Royal Society Interface, Biologists Dr Nigel Raine and Dr Steven Le Comber at Queen Mary, University of London used a technique called geographic profiling (GP) originally developed by Professor Kim Rossmo from Texas State University, a former detective and co-author, to help police narrow down suspects by looking at the locations of serial crimes.

Although it has been successful in practice, it is difficult for criminologists to test and improve GP scientifically because they can't ethically conduct controlled studies of criminals. But the better the technique, the more precisely the police can locate the criminal.

So Raine and his colleagues took GP into the laboratory and found that it helped to predict the entrance to a beehive from the locations of the artificial flowers visited by the bees. Furthermore, the technique allowed the researchers to distinguish different foraging strategies that the bees might be using. According to the study, for example, one likely strategy simply involves choosing the nearest new flower at each step from the nest.

The researchers say their findings have implications for bee conservation. Although there are 25 species of bumblebee in the UK, most of these are in decline as changes in agriculture have eroded their natural habitats. "Since records began, 3 bumblebee species have already become nationally extinct" says Raine. The great yellow bumblebee (Bombus distinguendus), for example, one of 5 species officially listed as priorities for conservation action by the government, is now found in only a handful of places such as the outer Hebrides. GP could help conservationists locate bumblebees' nests, a difficult task according to Raine, as they are usually underground and the bees may travel up to 2km from the nest.

Although this is the first controlled study of GP, Raine explained that "the approach works well for very different animals: from bees and bats to great white sharks". Following on from this work, the scientists plan to use GP "to study the distribution patterns of illegal snares in Zimbabwe" and to examine "how geographic profiling might assist in efforts to fight malaria by locating breeding sites".

GP uses two opposing insights to create a geoprofile that shows where a serial criminal is likely to live. Most crimes are committed near an anchor point, usually the criminal's home. 70% of arsons happen within 2 miles of the arsonists home, for example. However, there is also a buffer zone centred on the anchor point where there are few opportunities to commit a crime. For the bees, there is a energy cost attached to foraging further from the nest while the buffer zone might reflect the cost of attracting parasites and predators to the nest, according to Raine.

The researchers point out that while criminologists have no control over where crimes are committed, biologists can test GP under different conditions by experimentally controlling factors such as the distribution and density of the flowers. According to Rossmo, the research is relevant to analysing "track data from GPS monitored offenders" and "provides a foundation for possible future applications of geographic profiling to bioterrorism".