Making a beeline for hidden explosives

THEY may seem unlikely minehunters but honey bees are proving better than sniffer dogs at uncovering explosives.

Successful trials by Scots scientists have used the insects to root out mines in a former war zone.

Honey bees led clearance teams to unexploded devices in Croatia, after they were trained to hone in on their scent.

Dr Ross Gillander, a physicist with St Andrews University, helped design equipment that detects if bees are returning to the hive with tiny traces of explosives.

Once confirmed, footage from drones is used to pinpoint the spot where the insects picked up the telltale specks.

The bees could prove more effective than sniffer dogs because they can work for longer and are cheaper to use.

The promising early results offer hope that more of the 110million abandoned mines worldwide could be cleared more quickly – saving tens of thousands from injury or death.

Tests started in Croatia in November last year, funded by Nato’s Science for Peace and Security programme.

Bees from local hives are trained over two days by placing sugar syrup on top of TNT.

Dr Gillander said: ‘Basically, we teach them by a version of reward like you do with dogs. The bees fly out of their hive to go about their normal day-to-day job of finding pollen but instead of finding pollen they find explosives. It’s the sugar syrup which draws them out. ‘The training takes two days and is much faster and more efficient than training a dog. However, after three days the bees realise that they aren’t getting reward from the TNT and are disinterested in it. After three days we have to re-train the bees.’ Dogs work for only 15 minutes at a time and are more expensive to train. Bees will work tirelessly and are not affected by the chemical compounds in explosives, unlike canines, and can also reach areas that dogs cannot. However, rain and darkness will deter bees from going out.

Dr Gillander designed the equipment that tests the bees for explosives – a canvas-type material which is exposed to light. He said: ‘A drop in light emission [like a light dimmer switch] confirms the presence of explosives.’

Once explosives are confirmed, the team views records from a drone which hovers above the bees on their expeditions.

Precise details of the tests are being kept under wraps but Dr Gillander said the use of bees looked ‘promising’.