Left Menu
Development News Edition

North America's bird shrinkage documented, with a crash and a splat


North America's bird shrinkage documented, with a crash and a splat
Image Credit: Pixabay

Since 1978, researchers have scooped up and measured tens of thousands of birds that died after crashing into buildings in Chicago during spring and fall migrations. Their work has documented what might be called the incredible shrinking bird.

A study published on Wednesday involving 70,716 birds killed from 1978 through 2016 in such collisions in the third-largest U.S. city found that their average body sizes steadily declined over that time, though their wingspans increased. The results suggest that a warming climate is driving down the size of certain bird species in North America and perhaps around the world, the researchers said. They cited a phenomenon called Bergmann's rule, in which individuals within a species tend to be smaller in warmer regions and larger in colder regions, as a reason to believe that species may become smaller over time as temperatures rise.

The study focused on 52 species - mostly songbirds dominated by various sparrows, warblers and thrushes - that breed in cold regions of North America and spend their winters in locations south of Chicago. The researchers measured and weighed a parade of birds that crashed into building windows and went splat onto the ground. Over the four decades, body size decreased in all 52 species. The average body mass fell by 2.6%. Leg bone length dropped by 2.4%. The wingspans increased by 1.3%, possibly to enable the species to continue to make long migrations even with smaller bodies.

"In other words, climate change seems to be changing both the size and shape of these species," said biologist Brian Weeks of the University of Michigan's School for Environment and Sustainability, lead author of the study published in the journal Ecology Letters. "Virtually everyone agrees that the climate is warming, but examples of just how that is affecting the natural world are only now coming to light," added Dave Willard, collections manager emeritus at the Field Museum in Chicago who measured all the birds.

The study provides fresh evidence of worrisome trends for North American birds. A study published in September documented a 29% avian population drop in the United States and Canada since 1970 and a net loss of about 2.9 billion birds. "I think the message to take away is this," Weeks said. "As humans change the world at an unprecedented rate and scale, there are likely widespread and consistent biotic responses to environmental change."

(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)


TRENDING

OPINION/BLOG/INTERVIEW

Hyderabad Encounter: Time to review modern judiciary and restore people’s confidence

Its probably for the first time in the history of independent India, the parliamentarians, chief ministers and ministers in the Union and State governments are openly supporting an encounter. This indicates the people from top to bottom hav...

What happens to your outstanding loans if the bank falls?

... ...

Time for a change! Innovations to stop the growing plastic pollution

As the planet is drowning in plastic pollution, many new innovative approaches and solutions have emerged to effectively deal with the menace....

How to avoid fake universities and fishing bait like Farmington

As education sharks are roaming around to prey, we present a guide on how to mitigate hunters and reach to a genuine universityinstitute. In this era of commercialization of education, the fake universities and economic frauds in educationa...

Videos

Latest News

IMF reaches loan agreement of $5.5 billion with Ukraine

The International Monetary Fund IMF on Saturday announced that it has reached an agreement with Ukraine on a three-year loan of worth USD 5.5 billion. The announcement comes as Managing Director of the International Monetary Fund IMF held t...

Bangladesh to introduce virtual court: PM Hasina

Bangladesh government is planning to introduce a virtual court in the country, Prime Minister Sheikh Hasina has said.Speaking at the National Judicial Conference 2019 on Saturday, Hasina said that the court will reduce the risk and hassle o...

Australian firefighters try to control bushfires ahead of hot days

Firefighters in eastern Australia used easing weather conditions on Sunday to bring bushfires under control ahead of the forecast of soaring temperatures for next week.There were 96 fires burning in New South Wales, home to Australias large...

Cricket-Unsafe MCG pitch forces abandonment of Sheffield Shield match

A Sheffield Shield match at the Melbourne Cricket Ground was abandoned on Sunday because of a dangerous pitch, raising more questions about the fitness of the prestigious venue to host the Boxing Day test. The match hosted by Victoria was s...

Give Feedback