Could drones be hurting our wildlife?
While the boom in the drone market has caused worries among the aviation community - passenger planes are increasingly having run-ins with the flying machines - researchers say policymakers have overlooked the disturbance they cause to animals.
Now, a University of Waikato study has reviewed what regulations are in place relating to drones and wildlife, finding lawmakers have been playing catch-up.
Lead author Dr Pip Wallace said she and her colleagues had been moved to look into the issue after studying Waikato's coastal environment.
"We had been talking about the growing recreational use of drones and wanted to better understand potential impacts and limits of the regulatory framework."
Wallace said "it was the 'can anyone just fly drones anywhere?' question" that spurred them on.
After reviewing literature relating to drone benefits and issues, they found unmanaged use could cause disturbance effects to wildlife through low-altitude presence, noise and prevalence.
But these effects varied - and depended on the species, and the skill level of the drone's operator.
"We examined New Zealand law and policy, did a case study concerning local authority approaches and then did a comparative exercise examining the position in other countries.
"We came to the conclusion that [drone] operations should be guided by specific policy addressing impacts to wildlife and, where necessary, regulated to prevent harm from disturbance."
The team recommended strong measures in New Zealand, including consideration of distance setbacks.
"New Zealand has high rates of threatened species many of which live outside protected reserves," she said.
"Areas like the New Zealand coastal environment combine high rates of threatened birds with intensifying human development and recreational activity."
At the same time, drone use was growing rapidly, with strong uptake from recreational users able to buy drones off the shelf, Wallace said.
"As contests for airspace grow, New Zealand needs more effective mechanisms to protect and conserve biodiversity in airspace habitat."
New Zealand's regulations for drone use are more relaxed than elsewhere in the world due to updated civil aviation rules introduced in 2015.
The Civil Aviation Authority was reviewing the rules.
The new study follows a 2015 study by University of Minnesota scientists, who used health-tracking collars to demonstrate how drones flown within 20 metres of bears caused them enough stress to raise their heart rate.