Geese, swans and ducks are easily startled by drones, scientists have found.
The flying machines are becoming increasingly common in the UK as the technology becomes cheaper and the devices easier to fly.
However, conservationists from the British Trust for Ornithology (BTO) found the presence of the whirring machines can trigger fear in the birds, causing them to flee.
Disturbances caused by drones could affect rare and protected species, causing them to waste energy and reduce time spent in winter feeding grounds, experts fear.
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Conservationists from the British Trust for Ornithology (BTO) found the presence of drones can trigger fear in waterbirds, causing them to flee. DIsturbances caused by drones could affect rare and protected species, causes birds to waste energy and reduce time spent in winter feeding grounds experts fear (stock)
Amazon and other firms currently have plans to deliver parcels by drone to people’s doorsteps.
The machines are also being used by farmers to check crops in far-away fields, and by gamekeepers on the lookout for poachers.
They are also being trialled as a means to bring medicine to people in hard-to-reach parts of the word, such as insulin for diabetics in the Aran Islands.
But the drones can scare flocks of species like curlews and other birds, which are becoming endangered, warned the British Trust for Ornithology today.
BTO scientists flew a commercially available quadcopter drone towards waterbird flocks in coastal, freshwater and arable crop farmland habitats.
While one researcher flew the drone at a standard speed and height towards the flock, another watched through a telescope to record any responses to the drone as it approached, including alarm calls, signs of heightened alertness and taking flight.
The BTO published their findings in the journal Bird Study.
Drones are also being used by farmers to check crops in far-away fields, and by gamekeepers on the lookout for poachers. But the drones can scare flocks of species like curlews and other birds which are becoming endangered, warned the British Trust for Ornithology today (stock)
The experiment revealed larger flocks were more likely to take flight than smaller flocks, and large flocks also took flight at a greater distance from the drone than smaller flocks.
Habitat also had a significant impact on the reaction of birds, as well as group size.
Birds at inland lochs, areas with lots of other human activity and noise, were unlikely to respond to the presence of a drone.
However, birds at coastal sites were more likely to respond, possibly due to being accustomed to lower noise levels.
Birds in arable farmland were particularly sensitive, the scientists found, likely a result of the need to be on the lookout for predators in the exposed area.
In a statement, the BTO said: ‘The mass proliferation of drones and the increasingly likelihood of commercial and recreational drone use taking place close to wildlife creates a new and potentially significant source of disturbance to wild birds.
‘Such disturbance, which could affect rare and protected species, causes birds to waste energy and reduces their feeding time.
‘In extreme cases, birds might stop using an area altogether, and be forced to feed elsewhere, where feeding opportunities may be poorer or the risk of predation higher.
‘This could be particularly harmful during the cold winter months, when vast numbers of waterbirds come to Britain from the Arctic to feed up before the breeding season.’
The lead researcher, David Jarrett, said ‘While we expected that the drone would cause large flocks to flush, we were surprised that birds hardly seemed to respond to the drone at all at those inland lochs where there was already lots of human activity taking place.
‘Hopefully this research can be used to help inform guidance and regulations on drone use in proximity to wild birds.’