The paper by Professor Rory Wilson and Dr Emily Shepard of the Department of Biosciences with Sergio Lambertucci of the National University of Comahue, Argentina, has been published in Science. The study shows that as humans increasingly use airspace for transportation, energy generation and surveillance, conflict with aerial animals has increased, but these aerial interactions are still often neglected when considering ecological consequences of human activities.

Crowded airspace – the effects

The study says that conflict is generally within the first 100 metres of the ground, where most flying animals operate and human activity is concentrated.  This is also where the majority of bird- aircraft collisions occur, which have resulted in more than two hundred people being killed, thousands of aircraft being damaged, and which costs more than $900 million a year in the USA alone.

Other effects of crowded airspace include:

• disruption to airflows which impacts on bird distribution and habitat
• disturbance to aerial micro-organisms such as bacteria  and algae which affects cloud chemistry and climate

Drones also affect the behaviour of some species of birds when they fly close to nests and may produce physiological reactions such as stress. Yet this is a new field and only one study has systematically examined the responses of birds to drones.

Effective airspace management

These negative ecological effects have prompted the research team to call for a more effective environment management of the airspace on a national and regional level and for more detailed understanding of the movement of aerial animals.

Professor Wilson said: “It is interesting to note that more is known about the routes of migrating animal that cross continents than those taken by animals in parks or towns. But detailed data on how animals use space is now needed which can help guide local planning decisions, building designs and measures that protect our wildlife.”

The research team also say that there are strong arguments for establishing airspace reserves in aerial wildlife hotspots and temporary reserves could be introduced to protect birds when they migrate while permanent ones could be used could protect daily animal movements.

Dr Shepard said: “One of the main challenges is to increase the awareness of the many ways we are altering the airspace. Appreciation of this, and the steps we can take to mitigate our impacts, should be embedded in planning decisions from local to regional scales, just as it is for other habitat types”. Overall, the authors suggest the priorities should include the identification of near-pristine areas where air reserves can be established, as well as areas of high human-wildlife conflict where more protective measures are required.

Pictures: Illustrations of bird-human activity in airspace courtesy of Fernando Ballejo, from Universidad Nacional de La Plata, Argentina.