
North American birds are getting smaller, a study published Wednesday in Ecology Letters has found, and scientists think the climate crisis is to blame.
Researchers from the University of Michigan and the Field Museum in Chicago studied 70,716 dead birds from 52 different species, including sparrows, thrushes and warblers, that were collected between 1978 and 2016, according to CNN. They found that 49 species got smaller by a statistically significant degree.
"We found almost all of the species were getting smaller," lead author and assistant professor at the University of Michigan's School for Environment and Sustainability Brian Weeks told BBC News. "The species were pretty diverse, but responding in a similar way. The consistency was shocking."
North American migratory birds have been getting smaller over the past 4 decades, & their wings have gotten longer.… https://t.co/JvHal9kTbd— U-M SEAS (@U-M SEAS)1575468032.0
Weeks found that the birds' lower leg bone shrank by 2.4 percent. At the same time, their wingspans increased by a mean of 1.3 percent. The scientists think that warmer temperatures reduced the birds' size, and wingspans increased to compensate, since smaller bodies mean less energy to power the birds through their long seasonal migrations.
"Migration is an incredibly taxing thing they do," Weeks told BBC News.
Animal species tend to be smaller in the warmer parts of their range, a phenomenon known as Bergmann's Rule, according to a University of Michigan press release. But while scientists have theorized animals could shrink as their habitats warmed due to climate change, there hasn't been clear evidence that it is in fact happening.
The University of Michigan researchers were able to find some because they had access to a unique dataset: Since 1978, Field Museum Collections Manager Emeritus Dave Willard has collected and catalogued more than 100,000 birds that died on the streets of Chicago after colliding with its skyscrapers. Willard told CNN he began collecting the birds when someone mentioned they were hitting the windows of the McCormick Place convention center, just a mile from the museum.
"Why let them go to waste when they could be specimens in a museum?" he told CNN.
Because of the efforts of Willard and a team of volunteers, researchers had access to a treasure trove of bird specimens during a period when their breeding grounds north of Chicago warmed by around one degree Celsius. The data didn't just show that the birds' bodies changed as temperatures warmed overall, it also showed them alter in response to shorter-term temperature changes.
"Periods of rapid warming are followed really closely by periods of decline in body size, and vice versa," Weeks said in the press release. "Being able to show that kind of detail in a morphological study is unique to our paper, as far as I know, and it's entirely due to the quality of the dataset that David Willard generated."
- Climate Change Is Making Animals Smaller - EcoWatch ›
- Climate Change Leading to Fatal Bird Conflicts - EcoWatch ›
- Hummingbirds Live in a More Colorful World, Study Confirms - EcoWatch ›
People across New England witnessed a dramatic celestial event Sunday night.
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.
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Smoke from wildfires may be more harmful to public health than other sources of particulate matter air pollution, according to a new study.
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>