I applaud the efforts of Maine Audubon to reduce the number of birds dying in window collisions across the state. With partners University of Southern Maine, The Portland Society of Architecture, and Avian Haven, they have launched BirdSafe Maine. Many people (including myself until recently) are unaware that somewhere between 388 million and 988 million birds die from building collisions each year (that’s an average of between 1 and 3 million birds per day) because glass windows appear invisible to them. Except for feral cats and habitat loss, building collisions kill more birds than any other human-induced cause of bird death, including wind turbines, poison, and oil pits.
The problem is that birds think that reflections on glass are a continuation of habitat — something they could fly right through. As a result, birds can collide into any location where unmarked glass is used, which includes large and small windows. One collision can cause the injury or death of a healthy bird. The hazard occurs at all scales of development, from residential houses to low-rise buildings to high-rise buildings.
The good news is that there are numerous architectural solutions to this problem, including screening; a de-emphasis on exterior glass; ultraviolet strips placed inside glass panels; exterior frits or stickers; and other measures. Glass manufacturers have recently expanded their product lines to include bird-friendly options that are also aesthetically pleasing and more energy efficient. The bad news is that many residential and corporate buildings in Portland (and beyond) were not designed to incorporate these solutions and/or the current owners have not taken the necessary steps to provide the appropriate window treatments.
In Portland, volunteers and students have been surveying routes during spring and fall migration seasons to record and photograph bird deaths. The data is emailed to birdstrike@maineaudubon.org and weekly reports are shared. The fall of 2021 was the deadliest along the in-town Portland route in the history of the project: the final tally was an amazing 91 birds found between Sept. 7 and Oct. 1, nearly twice as many as the same period in 2020, when 55 birds were counted. Bird strikes were found all along the route, but they were most concentrated near buildings with the largest amount of glass. Species include Ruby-throated Hummingbird, Common Yellowthroat, White-throated Sparrow, Gray Catbird, Yellow-bellied Sapsucker, Lincoln’s Sparrow, Swamp Sparrow, Blackpoll Warbler, Northern Parula, Song Sparrow, and Palm Warbler.
Portland is in the middle of a construction boom, with lots of new buildings under construction or proposed for construction. Bird-safe window treatments should be part of their designs. Many cities and governments around the world have implemented guidelines and standards to incorporate bird-safe building materials and designs in new and existing buildings.
In the context of so many current challenges, the fate of birds may seem trifling. However, birds play a critical role in reducing and maintaining populations of insects in natural systems, providing plant pollination, and dispersing seeds. Not only that, but they are one of the most important “environmental indicators,” playing an essential role in the functioning of the world’s ecosystems in a way that directly impacts human health, economy and food production — as well as millions of other species (Source: Birdlife International.) Nearly three billion birds have disappeared across North America since 1970, which is often referred to as “an avian apocalypse.” This is devastating.
— Special to the Press Herald
Send questions/comments to the editors.