Hedgehogs are increasingly being killed and injured from encounters with robot lawnmowers which have few safety features to protect wildlife, according to Oxford University scientists.
Researchers conducted a series of tests with the mowers, the latest must-have garden gadget, with a view to create a ‘hedgehog friendly’ certification so gardeners need not fear any prickly casualties when they trim the grass.
To ensure no harm was caused to living hedgehogs, scientists used rubber ‘crash test hedgehogs’ instead to see if the robot mower would turn away on encountering one of Mrs Tiggywinkle’s tribe on the lawn.
Hedgehogs are already in serious decline, with reasons including habitat loss, road traffic accidents, intensive agriculture, and injuries from dog bites and garden strimmers.
But now mowers are adding to the threats.
Researchers from the University of Oxford have created a series of tests to create ‘hedgehog friendly’ robot mowers that won’t mutilate the prickly mammals when they come to stay in our gardens
The researchers said ‘many hedgehog rehabilitation centres have reported a significant increase in the numbers of hedgehog injuries caused by robotic lawnmowers.’
Dr Sophie Lund Rasmussen of Oxford University said: ‘There is an urgent need to identify and phase out models of robotic lawnmowers that pose a threat to hedgehogs.
‘Our new standardised safety test will greatly aid hedgehog conservation, by enabling manufacturers of robotic lawnmowers to ensure their models are “hedgehog friendly” before they are put on the market.’
The researchers tested the responses of fifty hedgehogs in an enclosed environment to a disarmed (bladeless) robotic lawnmower that was stopped 50 cm away from the hedgehog.
Overall, the hedgehogs showed three responses: running away from the mower; standing rigidly in front of it partially curled up; or sniffing the lawnmower inquisitively.
Robot mowers like this Honda Miimo might be help humans relax but they can be a nightmare for hedgehogs which are often caught in the blades of passing mowers
Generally, younger hedgehogs were bolder than adult hedgehogs.
Based on the responses of the living hedgehogs, they made rubber hedgehogs for use in safety tests, which are available for manufactures to create using 3d printers.
Ultimately, the researchers hope that the hedgehog safety test using the dummies will become standard on the UK and European markets.
To make mowers more hedgehog friendly, sensors that can detect hedgehogs and blades that retract when they hit anything harder than grass need to be used, the authors suggest.
Co-author Dr Anne Berger of the Leibniz Institute for Zoo and Wildlife Research, said: ‘Cut injuries from robotic lawnmowers are placing an enormous burden on many hedgehog care centres and using up important resources, as these injuries often require above-average care and treatment,’ with the victims found days or weeks after the accident.
Fay Vass, Chief Executive at the British Hedgehog Preservation Society added: ‘Hopefully, the results of this work will stop or drastically reduce the risk of robotic lawnmowers causing harm to hedgehogs.’
The research has been backed by mower makers STIHL and Husqvarna.
