Take a look outside. There's a better than 0% chance that the sky has not fallen. What has fallen, though, is the number of birds in that sky. An alarming new study is claiming that we (North America) have lost nearly a third of our bird population in the last half century.
This is disturbing to me because I love birds. We have several feeders in our yard and it's not unusual to see scads of them, including chickadees, juncos, rufous-sided towhees, flickers, woodpeckers, finches, nuthatches -- well, you get the idea. But, it appears that once again mankind's "progress" is to blame -- along with cats -- for their severe decline. That's right. What I thought to be an absurd statement was tempered a little when I read that house and feral cats account for consuming -- or at least killing -- over a billion of our feathered friends. We don't own a cat, but I have seen our neighbor's feline snag a bird or two in our yard over the years.
I am a little leery about so-called "studies", with skewed data in favor of the interest of corporations and organizations who fund them. However, the information provided by this study and first reported at sciencemag.org is compelling.
I am reminded of that great Hitchcock thriller, THE BIRDS, where tens of thousands of birds descended on a small California coastal town. I have watched the nightly swarms of thousands of crows and ravens flying north in the evening to roost a few miles away in the trees of a local college campus, and it is an awesome sight. While it's unlikely any time soon, I can't imagine looking up at the sky and never seeing them again.
Following is information on this issue culled from several sources.
Humans are responsible for most of the threats to birds. Expanding and intensifying agriculture and forestry, the biggest problems, cause habitat destruction, degradation and fragmentation. Fisheries degrade the marine environment and kill seabirds through accidental bycatch. The spread of invasive alien species, pollution and over-exploitation of wild birds are also major threats.
The threats leading to population declines in birds are many and varied: agriculture, logging, and invasive species are the most severe, respectively affecting 1,126 (77%), 763 (52%) and 473 (32%) globally threatened species. These threats create stresses on bird populations in a range of ways, the most common being habitat destruction and degradation, which affect 1,354 (93%) threatened species. - Birdlife International
Silent Skies: Billions of North American Birds Have Vanished
Though waterfowl and raptor populations have made recoveries, bird populations have declined since 1970 across nearly all habitats
By Jim Daley on September 19, 2019
More than half a century ago, conservationist Rachel Carson sounded an alarm about human impacts on the natural world with her book Silent Spring. Its title alluded to the loss of twittering birds from natural habitats because of indiscriminate pesticide use, and the treatise spawned the modern conservation movement. But new research published Thursday in Science shows bird populations have continued to plummet in the past five decades, dropping by nearly three billion across North America—an overall decline of 29 percent from 1970.
Ken Rosenberg, the study’s lead author and a senior scientist at the Cornell Lab of Ornithology and the nonprofit American Bird Conservancy, says the magnitude of the decline could significantly affect the continent’s food webs and ecosystems. “We’re talking about pest control, we’re talking about pollination [and] seed dispersal,” he says, referring to the roles birds play in ecosystems. Because it is relatively easy to monitor birds, he adds, their presence or absence in a habitat can be a useful indicator of other environmental trends. Based on the paper’s results, he says, “we can be pretty sure that other parts of the ecosystem are also in decline and degradation.”
Rosenberg and his colleagues used data from citizen-science bird-population assessments, including the North American Breeding Bird Survey and the Audubon Christmas Bird Count, to estimate changes since 1970. In these yearly projects, thousands of volunteers perform “point counts,” tallying all the birds they can see and hear in a short time period at locations along designated routes. This method “is the gold standard in the field of ornithology to survey birds,” says Valerie Steen, an ecologist at the University of Rhode Island, who was not involved in the new study. The researchers say that because they estimated losses only in breeding populations, their results are conservative—meaning total bird losses could be even higher than they reported.
Grassland-dwelling birds such as sparrows and meadowlarks have been hit especially hard. According to the study, more than 700 million birds across 31 species that make their homes in fields and farmlands have vanished since 1970. Rosenberg says the most likely explanation involves changing agricultural practices. “The intensification of agriculture is happening all over the world, [as is] increased use of pesticides, as well as the continued conversion of the remaining grass and pastureland—and even native prairie” to cropland, he says. These changes impact grassland birds in myriad ways: Widely used pesticides kill insects that some birds rely on for food, and exposure to these chemicals can even delay migration. Converting land for agricultural use removes nesting habitat. Shorebirds—which nest in areas particularly susceptible to development and climate change and whose numbers were already dangerously low in 1970—have declined by more than a third.
The researchers also used data from 143 weather radar stations to estimate changes in the total biomass of migratory birds each year between 2007 and 2017. They found similar declines to what the data from volunteer counts showed, particularly along the U.S. East Coast. The survey and radar data “measure different things, but they come to the same conclusion,” says study co-author Adriaan Dokter, a migration ecologist at the Cornell Lab of Ornithology. The Atlantic Coast is an important migratory route for warblers, thrushes, spoonbills and many other birds that breed in North America and spend the winter in the Caribbean or in Central or South America, says wildlife biologist and head of the Smithsonian Migratory Bird Center T. Scott Sillett, who advised the researchers but was not involved in the work. “A lot of migratory habitat for shorebirds and wintering habitat has been lost,” Sillett says. “This study points out that we have a lot more work to do in terms of habitat protection.”
One bright spot the researchers found was that wetland birds have made recoveries, driven largely by increases among waterfowl such as ducks, geese and swans. “It’s because of the strong constituency of recreational waterfowl hunters who raised their voice, put money where their mouths are and saw to it that conservation programs and policies were put in place,” Rosenberg says. “Billions of dollars [were] invested into wetlands [and] into wildlife refuges. The North American Wetlands Conservation Act was enacted in the late 1980s. All of these things were responsible for the turnaround.” The study also found that raptors such as bald eagles have rebounded after legislation extended protections for these birds and banned the pesticide DDT—thanks in part to Silent Spring.
Sillett says that birders and bird enthusiasts could learn from hunters’ conservation efforts. “The rest of us who enjoy birds that are not game species, we’ve got to think of ways that we can contribute to their conservation,” such as taxing hiking or bird-watching equipment to support conservation programs, he says. “I think we all need to throw in a bit and think about how we can come up with a broader model of conserving our wildlife that’s patterned after the waterfowl program.”
Jim Daley is a science journalist based in Chicago.
[SOURCE: ScientificAmerican.com.]
North America Has Lost Nearly 3 Billion Birds Since 1970
BY ALEJANDRO DE LA GARZA
SEPTEMBER 19, 2019
Birds across the U.S. are disappearing, though many of us probably haven’t noticed.
Over the past half century, North American bird populations have undergone a quiet crisis, with scientists estimating the continent to have lost 29% of its total avian population, as revealed a new paper published in the journal Science on Thursday. That’s a loss of nearly 3 billion birds in the last half century.
“I would call it an imminent disaster,” says Ken Rosenberg, a conservation scientist at the Cornell Lab of Ornithology and the American Bird Conservancy, and the lead author on Thursday’s paper in Science. “We need to do something about it now, and we need to pay attention.”
Scientists have been tracking populations of threatened and endangered birds for years, and noted that some populations were in decline. But they assumed that those threatened species were being replaced by “generalist species,” or more adaptable birds that were better suited to deal with man-made changes to their environment.
“The bulk of that loss is occurring in the common species,” says Rosenberg. “It’s across every habitat.”
Grassland bird species showed the largest impacts, with more than half their number, over 700 million breeding individuals across 31 species, lost since 1970. Birds living in forests also showed massive hits, with total losses of more than a billion birds.
“Birds are really facing an unprecedented crisis due to human activity,” says Nicole Michel a senior quantitative ecologist with the National Audubon Society. “We really need to take action quickly.”
Scientists believe that the loss of bird populations is due to a variety of factors, chief among them habitat loss, intensifying agricultural production and disruption of coastal ecosystems, all of which are exacerbated by the intensifying impacts of anthropogenic climate change. In particular, the authors of the paper believe that the stunning losses of grassland bird populations are driven in large part by increased pesticide usage and habitat loss due to agriculture.
Not all species showed population declines, and many even showed gains over the decades, but the overall drop in bird populations was startling. Those broad declines may not be readily visible to the average bird watcher, but over decades of data the devastating trend becomes all too clear.
“The loss of that magnitude could signal an unraveling of ecological processes,” says Rosenberg. “People need to start paying attention to the birds around them, because if the loss continues we’re really going to notice it and feel it.”
To compile the report, Rosenberg and his colleagues looked at data from sources that tracked 529 species of birds in the continental United States and Canada, spanning far flung geographic areas and habitats. The scientists relied in large part on information gathered through the North American Breeding Birds Survey, a longstanding partnership between scientists and amateur bird watchers. Those efforts showed persistent declines in bird populations. And when the scientists used supercomputers to examined data from weather radar, which for the past decade has recorded the biomass of migrating birds passing overhead at night, they discovered similar population declines.
“This is groundbreaking because of the incorporation of the radar data,” explains Michel. That information, Michel explains, allowed scientists to count bird populations that breed in sparsely populated northern regions where people aren’t necessarily able to reach them, and also enabled the report authors to independently verify the survey data that showed massive population losses.
There was one ray of hope in the paper’s overall gloomy findings — wetland birds showed gains in population, probably due in part to the billions of dollars in investment that have been poured into wetlands protection and restoration. For the authors, those gains show that this crisis does not necessarily need to become a full-blown catastrophe, assuming government and citizens take action to protect bird species from further impacts.
“We’re at a point where we can reverse these declines,” says Rosenberg. “We need to be acting now.”
Public action is urgently needed, but Rosenberg also notes that there are measures that individual citizens can take to help sustain bird populations, like planting native species in gardens and keeping cats indoors.
For Michel, successes like the recovery of raptor populations after DDT, a potent pesticide, was banned show that we have not yet reached the point of no return for North American birds.
“This is a crisis and a warning call,” she says. “But birds are resilient if you give them a chance.”
[SOURCE: Time.com.]
7 Simple Actions To Help Birds
1. MAKE WINDOWS SAFER, DAY AND NIGHT
The challenge: Up to 1 billion birds are estimated to die each year after hitting windows in the United States and Canada. (source).
The cause: By day, birds perceive reflections in glass as habitat they can fly into. By night, migratory birds drawn in by city lights are at high risk of colliding with buildings.
These simple steps save birds: On the outside of the window, install screens or break up reflections—using film, paint, or Acopian BirdSavers or other string spaced no more than two inches high or two inches wide. (source).
Take it further: Work with businesses or public buildings to offer a contest for creative “window mural” designs that make windows safer for birds. Support legislation for bird-friendly building designs. Start a lights-out campaign in your city.
2. KEEP CATS INDOORS
The challenge: Cats are estimated to kill more than 2.6 billion birds annually in the U.S. and Canada (source). This is the #1 human-caused reason for the loss of birds, aside from habitat loss.
The cause: Cats can make great pets, but more than 110 million feral and pet cats now roam in the United States and Canada (source 1, source 2). These nonnative predators instinctively hunt and kill birds even when well fed.
Solutions that are good for cats and birds: Save birds and keep cats healthy by keeping cats indoors or creating an outdoor “catio.” You can also train your cat to walk on a leash.
Take it further: Speak out about the impacts of feral cat colonies in your neighborhood and on public lands. Unowned cats’ lives may be as short as two years because of disease and hardship, and they are responsible for more than two-thirds of birds killed by cats in North America (source 1, source 2).
3. REDUCE LAWN, PLANT NATIVES
The challenge: Birds have fewer places to safely rest during migration and to raise their young: More than 10 million acres of land in the United States were converted to developed land from 1982 to 1997 (source).
The cause: Lawns and pavement don’t offer enough food or shelter for many birds and other wildlife. With more than 63 million acres of lawn in the U.S. alone (source), there’s huge potential to support wildlife by replacing lawns with native plantings.
Take it further: Add native plants and watch birds come in. Native plants add interest and beauty to your yard and neighborhood, and provide shelter and nesting areas for birds. The nectar, seeds, berries, and insects will sustain birds and diverse wildlife.
4. AVOID PESTICIDES
The challenge: More than 1 billion pounds of pesticides are applied in the United States each year (source). The continent’s most widely used insecticides, called neonicotinoids or “neonics,” are lethal to birds and to the insects that birds consume. Common weed killers used around homes, such as 2, 4-D and glyphosate (used in Roundup), can be toxic to wildlife, and glyphosate has been declared a probable human carcinogen (source).
The cause: Pesticides that are toxic to birds can harm them directly through contact, or if they eat contaminated seeds or prey. Pesticides can also harm birds indirectly by reducing the number of insects that birds need to survive.
A healthy choice for you, your family, and birds: Consider purchasing organic food. Nearly 70% of produce sold in the U.S. contains pesticides (source). Reduce pesticides around your home and garden.
Take it further: Urge U.S. Representatives to cosponsor the Saving America’s Pollinators Act. The bill, H.R. 1337, requires the Environmental Protection Agency (EPA) to suspend registration of neonics.
5. DRINK COFFEE THAT’S GOOD FOR BIRDS
The challenge: Three-quarters of the world’s coffee farms grow their plants in the sun (source), destroying forests that birds and other wildlife need for food and shelter. Sun-grown coffee also often requires using environmentally harmful pesticides and fertilizers. On the other hand, shade-grown coffee preserves a forest canopy that helps migratory birds survive the winter.
The cause: Too few consumers are aware of the problems of sun coffee. Those who are aware may be reluctant to pay more for environmentally sustainable coffee.
Insist on shade-grown coffee that’s good for birds: It’s a win-win-win: it’s delicious, economically beneficial to coffee farmers, and helps more than 42 species of North American migratory songbirds that winter in coffee plantations, including orioles, warblers, and thrushes.
Take it further: Look for Bird-Friendly coffee, a certification from the Smithsonian Migratory Bird Center that also includes organic and fair trade standards. Educate coffee shops and grocery stores about shade-grown coffee.
6. PROTECT OUR PLANET FROM PLASTICS
The challenge: It’s estimated that 4,900 million metric tons of plastic have accumulated in landfills and in our environment worldwide (source), polluting our oceans and harming wildlife such as seabirds, whales, and turtles that mistakenly eat plastic, or become entangled in it.
The cause: Plastic takes more than 400 years to degrade, and 91% of plastics created are not recycled (source). Studies show that at least 80 seabird species ingest plastic (source), mistaking it for food. Cigarette lighters, toothbrushes, and other trash have been found in the stomachs of dead albatrosses.
Reduce your use of plastics: Avoid single-use plastics including bags, bottles, wraps, and disposable utensils. It’s far better to choose reusable items, but if you do have disposable plastic, be sure to recycle it.
Take it further: Advocate for bans of plastic bags, styrofoam, and straws. Encourage stores to offer incentives for reusable bags, and ask restaurants and other businesses to phase out single-use plastics.
7. WATCH BIRDS, SHARE WHAT YOU SEE
The challenge: 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. Monitoring birds is essential to help protect them, but tracking the health of the world’s 10,000 bird species is an immense challenge.
The cause: To understand how birds are faring, scientists need hundreds of thousands of people to report what they’re seeing in backyards, neighborhoods, and wild places around the world. Without this information, scientists will not have enough timely data to show where and when birds are declining around the world.
Enjoy birds while helping science and conservation: Join a project such as eBird, Project FeederWatch, a Christmas Bird Count, or a Breeding Bird Survey to record your bird observations. Your contributions will provide valuable information to show where birds are thriving—and where they need our help.
Take it further: Mobilize others in your community by organizing school groups or leading bird walks and submitting your counts to eBird. Support organizations that coordinate monitoring projects.
[SOURCE: #bringbirdsback.]