How you can help migrating birds
Canada warbler (Photo by Gerald Deboer)
Just last summer, Environment and Climate Change Canada released the 2019 State of Canada’s Birds Report on behalf of the North American Bird Conservation Initiative (NABCI), a group made up of many organizations and agencies that are supporting efforts to conserve birds and their habitats. Looking at the population trends of over 400 birds since 1970, the report issued a grim warning: the diversity and abundance of Canada’s birds are declining.
The report states that populations have declined due to habitat loss, unsustainable agricultural practices, climate change and pollution. But another crucial reason for bird mortalities taking place in our own backyards, is window strikes.
A comprehensive study from 2013 estimates that approximately 25 million bird mortalities from window strikes occur annually in Canada, representing the second biggest direct mortality of birds after domestic cats. Similar and more recent studies continue to show comparable trends in bird mortality numbers with 90 per cent of bird strikes mortalities occurring in residential homes, and less than 10 per cent caused from low profile commercial buildings, and one per cent from tall buildings.
Birds are an important part of nature; they provide insect and rodent population control, pollinate flowers, gardens and agricultural crops, and disperse seeds, while serving as a bio-indicator for the health of an ecosystem. As birds populations migrate south during the coming fall weeks, it’s important to protect them throughout their journey.
Daytime window strikes occur because birds are unable to perceive glass as a hard immovable surface when they see reflections or see vegetation directly through the glass. Birds may also perceive their own reflection as another bird in their territory and try to attack it. This happens most frequently in the spring when territoriality is high. Nighttime strikes occur when nocturnal migrants (including most songbirds) crash into lit windows, as lights divert nocturnal migrants from their original path.
Studies are showing that proximity to natural areas, migratory pathways and stop over habitat have a large influence on the risk of window collisions. Specific characteristics most likely to contribute to increased collision include homes located in suburban areas, large glass windows, highly reflective coatings on low-emissivity and UV glass, tall vegetation in front of windows, and bird feeders in close proximity to the house.
As birds migrate, there are a number of things that homeowners can do to help protect birds from window collisions.
• When possible, close blinds and curtains. Simply turning off lights causes the window to be more highly reflective of the outside environment, increasing the risk of collision.
• Hang visual obstructions on glass for a visual deterrent to window collisions.
• Place bird feeders at least 4.5 metres away from windows.
• Hang a parachute chord at 10-centimetre intervals on the exterior of the glass.
• Create a grid of dots, stripes or other shapes on the glass (with a mininum 5 centimetres of spacing between).
• Install mosquito screens on the outside surface of the window.
The Nature Conservancy of Canada is working to reverse bird declines through habitat protection, community involvement and coordinated conservation efforts. But by making small changes around your homes and businesses to prevent window strikes, you can also help protect bird populations.