Aston University scientists invent new rat trap
Scientists at a Birmingham university have come up with a new way of controlling rats to prevent the spread of poison-resistant animals.
Conventional traps use poisoned bait, but they have led some animals to build up an immunity, researchers at Aston University said.
So-called super-rats have been found across Britain.
A new trap devised at Aston University delivers a poison in spray form directly on to a rat's skin to kill it.
As the rat enters the trap it breaks a laser beam. An onboard computer then calculates the exact dosage required, depending on the size of the rat.
The project has been backed by the European Union, although the toxin used in the trap will still require separate approval from the body before commercial use.
In contrast to the new device, researchers said it was impossible to control the amount of poison that a rat consumes in a traditional trap, meaning many survive, develop an immunity and have even started to pass that on to their offspring.
According to local authorities in the West Midlands, some 48,500 rat control treatments were carried out in 2013, making it one of the busiest areas in the country for call-outs.
Andrew Ingham, from Aston University, said pest controllers were often turning to higher and higher doses of traditional poisons to kill rats.
"You often don't notice there's a huge amount of poison hidden in a black box at the side of the road or at the side of your house," he said.