American Skyscrapers Kill an Estimated 600 Million Migratory Birds Each Year
An estimated 600 million birds are killed every year from collisions with some of the country's largest skyscrapers, according to research from the Cornell Lab of Ornithology. Particularly deadly are those tall buildings found in three cities in particular.
"Chicago, Houston, and Dallas are uniquely positioned in the heart of North America's most trafficked aerial corridors. This, in combination with being some of the largest cities in the U.S., make them a serious threat to the passage of migrants, regardless of season," said study lead author Kyle Horton.
The researchers cite artificial light at night as a contributing factor to heightened mortality numbers given almost one-half of the contiguous U.S. experiences substantial light-pollution during nighttime, including streetlights, safety lights and extensively lit buildings. These findings are especially troubling during migratory seasons in spring and fall, when billions of birds fly across the nation as they travel between North and South America. The birds normally depend on natural light from the moon, sun and stars to navigate.
Publishing their work in Frontiers and the Environment, researchers combined over two decades of satellite data showing light pollution levels with weather radar measuring bird migration from across 143 stations. Times and locations throughout the year showed when the highest numbers of migrating birds are exposed to light pollution.
Results indicate that avian light exposure in cities is 24 times as high as the countrywide average, potentially contributing to millions of birds fatally colliding with buildings, communications towers, power lines and wind turbines. Rankings of the most dangerous cities change with the season because birds change their migration routes between spring and fall. During the spring, billions of birds fly through the central U.S. between the Rocky and Appalachian Mountain ranges, with cities in the center of these areas being particularly deadly. A large spring migration along the West Coast also means Los Angeles is a particularly dangerous city. Meanwhile, fall migrations are most intense along the Atlantic seaboard, which experiences heavy light pollution.
Composite image of continental U.S. at night, 2016.
Though migrations during these times can last for months, the highest amount of birds can occur in just a few days. As the study notes, any one of the most dangerous cities can expect half of its annual bird-migration to pass through in just a week depending on wind conditions, temperature and timing.
And it's not just birds, either. Insects and bats can be negatively impacted as well.
The researchers hope their findings will help guide conservation efforts, particularly in urban centers, in an attempt to reduce lights at night. As the world begins to consider airspace as wildlife habitat, the research presents a "fundamental need to understand" how organisms interact with human-made infrastructure.
"Now that we know where and when the largest numbers of migratory birds pass heavily lit areas we can use this to help spur extra conservation efforts in these cities," said study co-author Cecilia Horton. "For example, Houston Audubon uses migration forecasts from the Lab's BirdCast program to run 'lights out' warnings on nights when large migratory movements are expected over the city."
Additionally, a quarter of a million birds die from running into residential buildings, and homeowners in both urban and rural settings can play a part in protecting avian species.
"If you don't need lights on, turn them off," Horton said. "It's a large-scale issue, but acting even at the very local level to reduce lighting can make a difference. While we're hopeful that major reductions in light pollution at the city level are on the horizon, we're excited that even small-scale actions can make a big difference."
A chestnut-sided warbler
Patricia Leonard, Cornell Lab of Ornithology
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EcoWatch Daily Newsletter
By David Reichmuth
Over the last month, I've seen a number of opinion articles attacking electric vehicles (EVs). Sadly, this comes as no surprise: now that the Biden administration is introducing federal policies to accelerate the roll out of electric vehicles, we were bound to see a reaction from those that oppose reducing climate changing emissions and petroleum use.
The majority of EVs sold in 2020 were models with a starting price (Manufacturers Suggested Retail Price) under $40,000 and only a fifth of models had a starting price over $60,000.
On Friday, China set out an economic blueprint for the next five years, which was expected to substantiate the goal set out last fall by President Xi Jinping for the country to reach net-zero emissions before 2060 and hit peak emissions by 2030.
The Great Trail in Canada is recognized as the world's longest recreational trail for hiking, biking, and cross-country skiing. Created by the Trans Canada Trail (TCT) and various partners, The Great Trail consists of a series of smaller, interconnected routes that stretch from St. John's to Vancouver and even into the Yukon and Northwest Territories. It took nearly 25 years to connect the 27,000 kilometers of greenway in ways that were safe and accessible to hikers. Now, thanks to a new partnership with the Canadian Paralympic Committee and AccessNow, the TCT is increasing accessibility throughout The Great Trail for people with disabilities.
Trans Canada Trail and AccessNow partnership for AccessOutdoors / Trails for All project. Mapping day at Stanley Park Seawall in Vancouver, British Columbia with Richard Peter. Alexa Fernando<p>This partnership also comes at a time when access to outdoor recreation is more important to Canadian citizens than ever. <a href="https://www150.statcan.gc.ca/n1/daily-quotidien/200527/dq200527b-eng.htm" target="_blank" rel="noopener noreferrer">Studies from the spring of 2020</a> indicate that Canadian's <a href="https://www.bnnbloomberg.ca/moneytalk-mental-health-during-covid-19-1.1567633" target="_blank" rel="noopener noreferrer">mental health has worsened</a> since the onset of social distancing protocols due to COVID-19. </p><p>The <a href="https://www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/safe-activities-during-covid19/art-20489385" target="_blank" rel="noopener noreferrer">Mayo Clinic</a> lists hiking, biking, and skiing as safe activities during COVID-19. Their website explains, "When you're outside, fresh air is constantly moving, dispersing these droplets. So you're less likely to breathe in enough of the respiratory droplets containing the virus that causes COVID-19 to become infected."</p><p>TCT leadership took this into consideration when embarking on the accessibility project. McMahon explains that there has never been a more important time to bring accessibility to the great outdoors: "Canadians have told us that during these difficult times, they value access to natural spaces to stay active, take care of their mental health, and socially connect with others while respecting physical distancing and public health directives. This partnership is incredibly important especially now as trails have become a lifeline for Canadians."</p><p>Together, these organizations are paving the way for better physical and mental health among all Canadians. To learn more about the TCT's mission and initiatives, check out their <a href="https://thegreattrail.ca/stories/" target="_blank">trail stories</a> and <a href="https://thegreattrail.ca/wp-content/uploads/2021/01/TCT_2020-Donor-Impact-Report_EN_8.5x14-web.pdf" target="_blank">2020 Impact Report</a>.</p>