Birds are rapidly vanishing from North America, with dramatic population losses in places that were once thought safe.
Great egrets and little blue herons. Blue-winged warblers and yellow-bellied sapsuckers. Snowy owls and tropical kingbirds.
Across North America, three-fourths of bird species are in decline, according to a sweeping study of avian populations published Thursday, the latest sign of a slow-moving extinction crisis that threatens entire ecosystems.
The population losses among the continent’s birds — red-winged blackbirds belting conk-la-ree! in marshlands, chickadees gathering around suburban bird feeders, peregrine falcons swooping between skyscrapers — should serve as a canary in the coal mine for people who live alongside birds, scientists say.
For a majority of bird species, the decrease observed between 2007 and 2021 was greatest in the places where they are most abundant, suggesting birds are struggling even in their strongholds.
“Those locations where species were once thriving, and where the environment and habitat was once really suitable for them, are now the places where they’re suffering the most,” said Alison Johnston, an ecological statistician at the University of St. Andrews in Scotland who led the research published in the journal Science.
“That was the most concerning finding,” Johnston said.
The study builds on research published in 2019 that used radar data to find that North America had lost more than 3 billion birds between 1970 and 2017. The new study doesn’t offer an update of that number or determine whether the overall bird population is declining faster than before. Instead, it took a more granular geographic look at the population trends of nearly 495 bird species.
Johnston’s team analyzed a robust online database called eBird, which collects more than 100 million bird sightings by professional ornithologists and amateur birders around the world every year.
“Birders have been keeping logs in their journals for 100 years or more. It’s just part of birding,” said Ken Rosenberg, a retired conservation scientist at the Cornell Lab of Ornithology who was part of the team that designed and launched eBird in 2002. “So there had been this dream, this vision of, like, what if we could harness all that information?”
Using a machine learning model to account for changes in how people observed birds over time, the researchers found that 75 percent of the documented species were in decline.
The result “reinforces the known pattern of mass decline,” said Richard Gregory, a University College London professor not involved in the research. “Taken as a whole, and depressingly, the heavy weight of evidence points towards a worsening situation for North American birds.”
There is no one single reason for this new silent spring. For many grassland species, farms are engulfing habitats and showering pesticides on insects that many birds eat. Along coastlines, construction and other activity are eating into beaches and wetlands where birds feed and nest. In the Arctic, rising temperatures are morphing critical breeding habitats.
There are still reasons for hope in the findings. For the vast majority of bird species in the study, there are pockets where subpopulations were stable or even growing. That granular analysis could help scientists and government officials better understand the factors allowing particular birds to thrive, which could inform how to protect whole species.
But the federal government under President Donald Trump is pushing forward with regulatory changes that weaken a century-old law protecting migratory birds and permit more mining, construction and other activities even if they destroys the habitats of endangered birds and other species.
Amanda Rodewald, a Cornell ecologist who co-wrote the study, noted that some of the same pressures weighing on birds, such as climate change and air pollution, are also bad for human health and well-being.
“Humans share those same environments,” Rodewald said. “So if they’re not healthy enough for birds, they’re unlikely to be healthy enough for people, too.”
And what say you, Google A.I. ?
Here's a more detailed explanation:
1. What is a Mass Extinction?
Mass extinctions are characterized by a rapid and significant decline in global biodiversity, often leading to the extinction of at least 75% of existing species within a relatively short geological timeframe (less than 2 million years).
There have been five major mass extinction events in Earth's history, each marked by catastrophic shifts in the global environment.
2. The Sixth Extinction:
The Sixth Extinction is a term used to describe the ongoing, human-driven mass extinction event.
It's unique in that it's primarily caused by human activities, including habitat destruction, climate change, pollution, and overexploitation of resources.
Scientists are increasingly concerned about the current rate of biodiversity loss, which is significantly faster than the natural background rate.
This accelerated rate of extinction is causing alarm because it could lead to the loss of essential ecosystem services, and potentially cause irreversible damage to the planet's ecosystems.
3. Causes of the Sixth Extinction:
Habitat loss and fragmentation:
- As human populations grow and develop, natural habitats are destroyed and fragmented, making it difficult for species to find food, shelter, and breeding grounds.
Climate change:
- Human-caused greenhouse gas emissions are leading to rising global temperatures, which are causing significant shifts in climate patterns, affecting habitats and species distributions.
Pollution:
- Pollution from industrial activities, agriculture, and other sources can harm or kill species, disrupting ecosystems and reducing biodiversity.
Overexploitation:
- Overfishing, overhunting, and unsustainable resource extraction can deplete populations of certain species, making them vulnerable to extinction.
Loss of ecosystem services:
- Ecosystem services, such as clean water, air, fertile soil, and pollination, are essential for human survival and well-being. The loss of biodiversity can disrupt these services, impacting human health and livelihoods.
Impact on human health:
- The loss of certain species could lead to the loss of potential medicines and other beneficial substances, impacting human health and well-being.
Uncertainty and instability:
- The loss of biodiversity can create instability in ecosystems, making them more vulnerable to disruptions and potentially leading to cascading effects that affect other species and the environment.
Reduce our carbon footprint:
- Transitioning to renewable energy sources, improving energy efficiency, and reducing our consumption patterns can help mitigate the effects of climate change.
Protect and restore habitats:
- Establishing protected areas, restoring degraded habitats, and promoting sustainable land use practices can help preserve biodiversity.
Address pollution:
- Reducing pollution from industrial sources, agriculture, and other sources can help protect species and ecosystems.
Promote sustainable consumption:
- Making conscious choices about the products we buy and how we use them can help reduce our impact on the environment.
Support conservation efforts:
- Funding and supporting conservation organizations and initiatives can help protect species and habitats.
At the current rate, we'll be head-first and ankle-deep in our own shit in the next decade.
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