Drones, robots and unmanned submarines used to be for military use only. But these days the technology is rapidly advancing and becoming more available for emergency services, farmers, film-makers or the public at large.
Those of us working in wildlife research and management also recognise the potential of unmanned vehicles. Across the world today these machines are being used to monitor migrating birds, spawning salmon and orangutans, to map breeding habitats of endangered species, to track threatened caribou and polar bears in the far north, to examine nest contents of birds breeding in inaccessible locations, and to deter poachers in Africa.
As technology and industry continue to develop and the regulatory procedures begin to loosen, we’ll see conservation drones used in even more different ways in the field of wildlife biology. It’s something we’ve been researching at McGill University in Montreal since 2007. Here are a few of the things we are engaged in.
Spying on birds and their nests
We spent our first years using a small fixed-wing drone to successfully fly over and count flocks of Canada and snow geese. Next, we used the plane to count terns nesting in a large colony in New Brunswick, and were also able to map their favoured nesting habitat. We managed the same for threatened least bitterns in southern Quebec.
Efforts to learn about and protect birds of prey are sometimes hampered by their nesting locations – often found in remote areas, on rocky ledges or high up in tall trees. The number one source of mortality on the job for wildlife biologists is dying in a light plane or helicopter crash. A better way to monitor the contents of raptor nests is to use a small GoPro camera attached to a light-weight rotary-winged drone.
So far we have used such a machine to survey the nests of ospreys, bald eagles, ferruginous hawks and red-tailed hawks – 113 flights in all. We obtained high-quality images of the nest contents in the vast majority of flights, allowing for an accurate count of eggs or nestlings, as well as useful estimates of the nestling ages.
More importantly, at each nest, we measured how the parents responded to the unexpected visitor. We recorded key behaviour such as how far the birds initially flew away or whether they demonstrated aggressive defensive behaviour, calling out or attacking the drone.
Finally, we approached active nests on foot without flying the aircraft, but still recording parental behaviour. This allowed us to sort out the amount of disturbance caused specifically by the drone versus only human presence at the nest site.
Our work demonstrates that drone aircraft can be a valuable tool for monitoring raptor nests, allowing for a flexible schedule of quick checks with minimal disturbance. Drones are also safer and more accurate than nest checking from light manned aircraft.
Drones can help conservation efforts in non-avian animals too. In Goose Bay, Labrador on Canada’s remote north eastern coast, we attempted to compare the use of a fixed-wing drone with a manned helicopter to acquire images of woodland caribou. The imagery obtained was sufficiently high quality for us to find and identify caribou and even differentiate between adults and calves.
Of course sometimes we may miss animals because they are obscured by trees or boulders, but we are hoping to be able to factor this into our analyses. We are currently working on estimating the necessary corrections by conducting some detectability studies using plywood sheets as surrogate caribou targets placed in various kinds of habitats, using open versus dense. Eventually we hope to use drones to survey large areas and estimate caribou numbers.
Flying, noisy scarecrows
Drones aren’t just used for conserving endangered species – they might also help manage unwanted invaders such as the European starling. These birds were first introduced to North America in 1890 when 60 birds were released in New York. Today, they number 200 million across the continent. Starlings compete with native birds for food and nest sites and a flock can decimate food crops, especially vineyards.
Scaring starlings away from grape crops using stationary propane cannons is ineffective and shooting them with guns is destructive, but what if dispersing these birds could be done non-lethally by using drones?
We have designed a mount to attach 4 bear-bangers (loud noise-makers) to a small octacopter. We have conducted some banger firing tests to confirm that everything works safely, and we will begin test flights in several vineyards in the Okanagan Valley in British Columbia later this year.
Another area of interest to us is tracking wildlife bearing radio transmitters. The objective is to mount an antenna/receiver that will not only pick up signals from the transmitters on the animals so as to identify individuals but also relay the information to a ground station.
As a test case, we are attempting to develop a receiver small and light enough to be affixed to a rotary drone so that we can pick up signals from song sparrows nesting on the Gulf Islands in British Columbia to know that the birds have returned from their wintering grounds. Thus far, we have been able to mount a receiver on a rotary drone and successfully determined that it can pick up signals from transmitters. Field tests on the wild sparrows begin in 2015.