Air transport has become essential to the movement of goods and people throughout the world. As with other forms of travel though it comes with a cost to wildlife. The primary risk to animals from air traffic in Canada is wildlife strikes. Wildlife strikes can happen on land, water, and in the air with most incidents occurring at or near airports. The majority of collisions with aircraft involve birds but can also include mammals and any other species in the flight path.
Wildlife strikes related to aviation in Canada are tracked by Transport Canada, the federal department responsible for regulating the transportation industries operating in the country. Airlines and airports are required to monitor and act to minimize wildlife strikes, to reduce the risks to people, and the significant costs that are incurred from collisions. Not surprisingly, the frequency of wildlife strikes coincides with the busiest airports and the areas with the greatest number of birds. The 2021 Annual Strike Report produced by Transport Canada shows that most strikes occur during the takeoff and landing phases of flight. Bird and mammal strikes have increased nearly every year since 2005, peaking in 2019 at 2043 bird strikes and 108 mammal strikes in Canada. Wildlife strikes declined significantly at the height of the pandemic but records show they are increasing as air travel returns to normal.
Birds often congregate in the grassy fields surrounding airports, where they feed, rest, and sometimes nest. The number and species of birds reflects seasonal behaviours and weather conditions. Migratory birds may be present in the spring and fall as they stop along their journeys to rest and eat. Residential populations return to airfields as food and water sources become available. Birds may also choose airports as safe alternatives if they have been harassed or driven away from nearby properties such as farms or parks.
While not as common, other species such as moose, deer, coyotes, rabbits, bats, and frogs are also susceptible to aviation collisions in Canada. Although high fencing is common surrounding major airports, smaller airfields may not have the resources to fully enclose runways. In spite of the mitigation strategies employed by airports, many resourceful animals continue to access restricted areas, putting themselves at risk.
Float and bush planes are common in the rural regions of Canada. They often take off and land in remote areas where few to no measures are available to protect the aircraft and wildlife. Even in urban harbours with active airports, wildlife have unrestricted access and may stray in the path of moving aircraft. Although they account for a relatively small percentage of aircraft that traverse Canadian airspace, float and bush planes travel to areas of the country with the greatest concentrations of wildlife.
To give context to the issue of wildlife strikes, here are some statistics from the Wildlife Strikes at Canadian Airports for 2021:
1363 bird strikes were reported, including 1231 involving civilian aircraft and 132 military.
66 mammal strikes were reported, including 65 involving civilian aircraft and 1 military.
In 2019 at the height of air travel in Canada, 2043 bird strikes and 108 mammal strikes were reported.
Peak months were from May to October, occurring primarily in the hours of 07:00 to 15:00.
The top five airports reporting wildlife strikes in Canada in 2021 were:
Wildlife management for the aviation industry is regulated by the federal government in Canada and managed by airports. Their primary concerns are for the safety of passengers and crew and reducing expenses associated with wildlife strikes. While those objectives most often align with the protection of wildlife, their priorities supersede the wellbeing of animals and sometimes conflict with it.
There are a variety of methods currently being used to minimize the hazards to wildlife and people. Research and knowledge sharing throughout the industry can help to improve strategies and further mitigate the risks associated with flights. Understanding wildlife patterns, changing conditions, and external factors influencing wildlife behaviours will provide the airline industry with additional tools to respond appropriately. Organizations like the Bird Strike Association of Canada actively coordinate with members of the aviation community to share information and promote best practices.
Transport Canada requires that airports “implement wildlife control measures to discourage wildlife from seeking food, water, and shelter on or near airport property”. Airport authorities employ a range of techniques to harass and discourage wildlife with the goal of creating an inhospitable environment. The methods are categorized as passive and active management.
Examples of passive management include removing food sources and attractants as well as habitat alteration. Modifying habitat such as removing water sources, shelter sites, and perches disincentive wildlife from gathering on airport property. Active management refers to harassing, dispersing, and removing wildlife that access airport grounds. Transport Canada lists a range of methods in its publication titled “Sharing the Skies: An Aviation Industry Guide to the Management of Wildlife Hazards”, which range from “not recommended”, “limited recommendation”, and “highly recommended” as shown in the table below.
CCPC/Donna Feledichuk and CCPC/ Josh DeLeenheer
It’s important to note that killing wildlife is accepted practice by both the government and airport authorities, although other methods are typically attempted first. Wildlife are generally killed on airport properties “where specific individual birds or mammals cause persistent problems”. Animals that are selected for death are most often shot or poisoned. Poisoning wildlife can have unintended consequences though, sometimes leading to the deaths of species not targeted by the poison. Alternatively, animals may be live-trapped and released in other locations.
Aviation accounts for a relatively small percentage of the overall impacts of transportation to wildlife in Canada. The number of wildlife strikes and overall contribution to greenhouse gas (GHG) emissions are low compared to road transportation; however, that is also reflective of the number of flights in relation to the number of vehicles in operation. The GHG emissions per flight are considerably higher than other modes of transport and the overall trend is an increase in air traffic. The electrification of aircraft can help to reduce the impacts on climate change but currently only for shorter flights. Improvements in alternative fuels may also help to mitigate climate risks providing that there is adequate investment in production and the costs to the aviation industry are comparable.