The National Audubon Society recently released a comprehensive Climate Report summarizing 30 years of data including citizen-scientist observations from the North American Breeding Bird Survey, the Audubon Christmas Bird Count, and eBird. Included in the list are 314 bird species (more than half of all 588 North American bird species!) predicted to go extinct by the end of the century if we don’t prioritize conservation in future industry regulations and land/water management decisions. Sadly, over 25% of United States bird species have declined to such an extent they are officially listed as being of conservation concern. In addition to habitat loss and predation by outdoor cats, one of the primary causes of bird deaths is one that many people would never think of - window collisions. Birds don’t recognize transparent glass as a solid object so instead of avoiding it, they attempt to fly directly towards reflected habitat, or through the invisible surface. Although accurate quantification is difficult, it’s estimated that 300 million to 1 billion birds are killed annually by window collisions in North America alone. For many reasons migratory birds are especially vulnerable to anthropogenic forces. In particular, they depend on multiple habitats including their breeding and overwintering habitats and that which lies along their entire migration route. Habitat loss is considered the primary cause of bird population declines, but one could easily make the case that building large glass structures in the middle of a migration path would also qualify as habitat loss. It’s estimated that 5% (1 in 20!) of fall migratory birds meet their deaths by colliding into one of our windows. This is a tragically large number. The thing about migratory birds is that many of them travel by night or at high elevations so we don’t even see them. Here is an example of a NEXRAD imaging photo capturing bird migration. In addition to the increase in densities, migratory birds navigate towards light and are thus attracted to our lit windows. This is why programs such as “Lights Out” have been so effective. FLAP (Fatal Light Awareness Program), Chicago Bird Collisions Monitor, and other Audubon Lights Out programs in North America. THE PROBLEMS The primary factors leading to high numbers of bird-window collisions (BWC) are: Tunneling: the effect created by glass-faced buildings coupled with interiorly lit objects (Klem et al., 2009 and Martin, 2011).Transparency: birds cannot detect the presence of glass and attempt to fly through (Johnson and Hudson, 1976).Reflectivity: glass reflects habitat and open space causing collisions (Banks, 1976)Adjacent habitat: attracts birds and is reflected in buildings (Gelb and Delacretaz, 2006).Migration: increases the number of birds which pass through an area exponentially, particularly birds that are not adapted for urban buildings (Codoner, 1995 and Collins et al., 2008).THE SOLUTIONS Based on count data, it’s actually thought that majority of total bird window collisions occur at people’s homes. You might not think that bird-safing your windows at home or at your work-place will make much of a difference, but you very well could save dozens of birds by doing so. There are a number of different things you can do to your windows to prevent bird strikes. In addition, these are 3 simple practices that will reduce risks at home: Move feeders close to your windows — 1.5 feet or closer. From this distance, birds won’t be able to build up enough momentum to hurt themselves if they do fly against the glass.Close curtain and blinds when possible to break up the illusion of clear passage or reflected habitat.Move houseplants away from windows. Birds may view them as refuges and try to perch on them. Here is a recent National Geographic article “How Better Glass can Save Hundreds of Millions of Birds per Year,” which discusses some of the past and current research being done. THE CASE OF THE M