Nearly 3 Billion Birds Have Disappeared

North American birds are in peril with 29% of U.S. and Canadian bird populations having been lost since 1970. In a finding researchers called "staggering,"1 ornithologists analyzed decades of data from multiple and independent monitoring networks to estimate bird populations.2

A net loss of 2.9 billion birds occurred over the last 48 years,3 including not only rare species but also common birds at backyard feeders, such as sparrows, warblers, finches and blackbirds.4

Nineteen common bird species lost more than 50 million birds during the study period, with lead author and conservation scientist Ken Rosenberg telling CBS News, "We expected to see continuing declines of threatened species. But for the first time, the results also showed pervasive losses among common birds across all habitats, including backyard birds … There's an erosion of the numbers of common birds."5

Audubon Society Declares a 'Bird Emergency'

Bird losses aren't necessarily obvious, as there are still many birds in the environment. However, 12 bird families accounted for 90% of the bird declines, including among such familiar species as red-winged blackbirds, dark-eyed juncos and meadowlarks.

"There are still a lot of birds out there," Rosenberg told The Atlantic. "If you have a lot of birds coming to your feeder and they're reduced by 30 percent, you might not see that. This loss of abundance can be happening right under our noses."6

Thirty-one species of grassland birds were studied, for instance, with numbers down by 720 million, or 53%, since 1970.7 Species of shorebirds, including sanderlings and plovers, declined by about 33%.8 While the loss of more common birds such as sparrows may not be as sensational as losses of iconic species like bald eagles, their absence will still send ripples throughout the entire ecosystem.

In fact, Gerardo Ceballos, conservation biologist at the National Autonomous University of Mexico in Mexico City, told CBS News, "When you lose a common species, the impact will be much more massive on the ecosystem and ecosystem services."9

In addition to the population trajectories and size estimates indicating that nearly 3 billion birds have been lost since 1970, the study used a continent-wide weather radar network to determine that the mass of migratory birds has also dropped significantly — by13% — from 2007 to 2017, particularly among birds migrating along the eastern U.S.10

Birds are a vital part of the environment, acting as pollinators and pest controllers and helping to disperse seeds that help forests to grow. David Yarnold, president and CEO of National Audubon Society, called the losses a "bird emergency." He stated in a news release:11

"The connection between birds and humans is undeniable — we share the same fate. This is a bird emergency with a clear message: the natural world humans depend on is being paved, logged, eroded and polluted. You don't need to look hard for the metaphor: birds are the canaries in the coal mine that is the earth's future."

Why Are Birds Vanishing?

The study revealed a host of sobering statistics, like the fact that there are 93 million fewer white-throated sparrows today than there were in 1970, while 2 in 5 barn swallows have also been lost. Overall, 1 in 4 birds are gone, including 2.5 billion migratory birds.12 Some of the other worst losses since 1970 include:13

  • 9 in 10 evening grosbeaks
  • 500 million boreal forest birds
  • 3 in 4 Eastern meadowlarks
  • 170 million Eastern forest birds
  • 160 million aerial insectivores

While the exact causes of the declines go beyond the scope of this study, the scientists concluded, "The disappearance of even common species indicates a general shift in our ecosystems' ability to support basic birdlife."14 Habitat loss was singled out as the greatest overall driver of bird declines, followed by habitat degradation.

Habitat loss refers to instances when land is converted for other uses, such as agriculture or development. When habitat is degraded, it may not disappear entirely but becomes altered, fragmented or compromised in a way that makes it less able to support bird life.

Since the early 1800s, grasslands in North America have decreased by 79% — and in some areas by 99.9%,15 largely to plant vast swaths of chemically intensive genetically engineered (GE) corn and soy.

Pesticides were also mentioned as causing both direct and indirect threats to birds. Not only do these chemicals contribute to bird poisonings but they also reduce the number of insects and other sources of food for birds. The number of birds harmed by pesticides is difficult to put numbers on, the study noted, but a study by Environment Canada in 2013 suggested agricultural pesticides may lead to 2.7 million bird losses annually.16

Birds exposed to widely used neurotoxic pesticides called neonicotinoids were also found to feed less, accumulate less body mass and fat stores and ultimately delay migration, which can affect survival and reproduction.17 Aside from habitat loss and pesticide usage, some of the additional threats to birds include:


Window collisions


Power lines

Communication towers

Wind turbines

Insect Extinction Also Underway

Like birds, insects are declining at a dramatic rate, according to a scientific review, and modern-day agriculture is largely to blame. Worldwide, more than 40% of insect species are threatened with extinction in the next few decades.18

Lepidoptera, insects that include butterflies and moths, hymenoptera, which are insects that include bees, and dung beetles are those most at risk on land. As for aquatic insects, those most affected include those in the odonatan order (dragonflies and damselflies), along with plecoptera (stoneflies), trichoptera (caddisflies) and ephemeroptera (mayflies).

Overall, the total mass of insects is said to be falling by a "shocking" 2.5% a year. If this rate continues unchecked, insects could disappear within 100 years. "It is very rapid. In 10 years you will have a quarter less, in 50 years only half left and in 100 years you will have none," study author Francisco Sánchez-Bayo, at the University of Sydney, Australia, told The Guardian.19

As with birds, the researchers cited compelling evidence that agricultural intensification is the main driver of population declines in birds, small mammals and insects. In order of importance, habitat loss due to land converted to intensive agriculture, as well as urbanization, are major problems. The next most significant contributor is pollution, primarily that from synthetic pesticides and fertilizers.

The Green Revolution Looks Pretty Dark

The Green Revolution sounds beneficial but it actually describes the conversion of natural, traditional farming — when all food was grown organically in concert with nature and surrounding ecosystems — to a system dependent on chemicals and industry.

The Rockefeller Foundation funded the Green Revolution that led to the introduction of petroleum-based agricultural chemicals, which quickly transformed agriculture, both in the U.S. and abroad. Monoculture was the outcome, with a focus on monocrops, i.e., growing acre upon acre of only one crop at a time. The very definition of monoculture is a system of agriculture with very little diversity.

It defines the wide swaths of corn and soy being grown across the U.S. and worldwide, a significant portion of which is, in turn, fed to animals being raised on CAFOs (concentrated animal feeding operations). The massive loss of birds, which mirrors similar declines in other creatures such as insects, is a wake-up call that the future of the Green Revolution looks very dark — unless changes are urgently made.

The featured study's co-author Peter Marra, director of the Georgetown Environment Initiative, told CBS News, "This is being caused entirely by humans. Habitat loss, which is the primary driver here, is a human-caused issue."

The light at the end of the tunnel is biodynamic, regenerative agriculture, which is a savior to birds, insects and other species worldwide. A change from industrial agriculture to organic farming led to increases in the abundance and diversity of moths, for instance, and organic farms have been found to have an overall higher insect abundance than conventional farms.20,21

Further, in bird and habitat surveys of 45 sites in Wales, very few species were found on intensively managed sites, while those with unimproved grassland or improved grassland were found to be important for a variety of species.22

This is why, on an individual level, the best course of action to reduce the harm industrial agriculture and habitat loss is having on birds is to support biodynamic, grass fed farms that are conserving diversity and not relying on synthetic chemicals and other intensive agriculture practices.

Seven Simple Actions to Help Birds

In addition to supporting regenerative agriculture, there are simple actions you can take to make a difference for birds. The Audubon's Yarnold noted:23

"Since the 1970's, we've lost three billion of America's birds. This is a full-blown crisis that requires political leadership as well as mass individual action. We have to act now to protect the places we know birds rely on.

Places like the Arctic Refuge, Great Lakes, Everglades, and Colorado River must be a priority. From the newest Audubon members to the most tenured Senators, we all can act today to protect birds and the places they need."

3 Billion Birds, a partnership between Audubon, American Bird Conservancy, Bird Conservancy of the Rockies, Georgetown Environment Initiative, The Cornell Lab of Ornithology and Smithsonian, suggests everyone take the following seven simple actions to help birds now, before their populations decline even further:24

1. Make windows safer — Install screens or break up reflections using film, paint or string to prevent birds from hitting your windows.

2. Keep cats indoors — Free-roaming cats kill birds; give your cat environmental enrichment by providing a catio, a secure outdoor enclosure where your cat can enjoy the outdoors without harming birds.

3. Reduce your lawn, plant native plants instead — Lawns do little to support birds, while native plants sustain birds and provide shelter and nesting areas.

4. Avoid pesticides — They're toxic to birds and reduce insects, which birds rely on for food; avoid using pesticides in your home and garden and choose organic or biodynamic food produced without pesticides.

5. Choose shade-grown coffee — Sun-grown coffee contributes to forest destruction and requires pesticides and fertilizers; shade-grown coffee preserves forests and helps migratory birds survive the winter.

6. Avoid plastic — Plastic is polluting oceans and harming wildlife, including seabirds; avoid all forms of single-use plastics, including bags, bottles, straws, disposable utensils and wraps.

7. Watch birds and share — Monitoring birds is important to protect them. According to 3 Billion Birds, "The world's most abundant bird, the passenger pigeon, went extinct, and people didn't realize how quickly it was vanishing until it was too late."25

Researchers need help from citizen scientists to monitor birds in their own communities and report on what they see. A number of projects are underway, including Project FeederWatch and a Christmas Bird Count, so you can get involved watching birds in your own backyard.

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