North American Grassland Birds in Peril, Spurring All-out Effort to Save Birds and Habitat

When Reed Cammack hears the first meadowlark of spring, he knows his family has made it through another cold, snowy winter on the western South Dakota prairie. Nothing’s better, he says, than getting up at sunrise as the birds light up the area with song.

“It’s part of the flora and fauna of our Great Plains, and it’s beautiful to hear,” says Cammack, 42, a sixth-generation rancher who raises cattle on 4,047 hectares (10,000 acres) of mostly unaltered native grasslands.

But the number of returning birds has dropped steeply, despite seemingly ideal habitat. “There are quite a few I don’t see any more, and I don’t know for sure why,” says Cammack’s 92-year-old grandfather, Floyd, whose family has allowed conservation groups to install a high-tech tracking tower and conduct bird surveys.

North America’s grassland birds are deeply in trouble 50 years after adoption of the Endangered Species Act, with numbers plunging as habitat loss, land degradation and climate change threaten what remains of a once-vast ecosystem.

Over half the grassland bird population has been lost since 1970 — more than any other type of bird. Some species have declined 75% or more, and a quarter are in extreme peril.

And the 38% — 760,000 square kilometers (293,000 square miles) — of historic North American grasslands that remain are threatened by intensive farming and urbanization, and as trees once held at bay by periodic fires spread rapidly, consuming vital rangeland and grassland bird habitat.

Biologists, conservation groups, government agencies and, increasingly, farmers and ranchers are teaming up to stem or reverse losses.

Scientists are sharing survey and monitoring data and using sophisticated computer modeling to determine the biggest threats. They’re intensifying efforts to tag birds and installing radio telemetry towers to track their whereabouts. And they’re working with farmers and ranchers to implement best practices that ensure survival of their livelihoods and native birds — both dependent on a healthy ecosystem.

“Birds are the canary in the coal mine,” says Amanda Rodewald, senior director of the Center for Avian Population Studies at Cornell University’s ornithology lab. “They’re an early warning of environmental changes that also can affect us.”

Monitoring birds

Daniel Horton sets his timer, cocks his head and listens intently while standing in a fog-shrouded expanse of grasses and wildflowers, the morning horizon glowing pink and orange.

Trills, twitters, chirps and coos create a dawn chorus in the native mixed-grass prairie of western Nebraska, while Horton, a field biologist with the Bird Conservancy of the Rockies, records everything he sees and hears on grazing land improved by a local rancher.

Western meadowlarks sing atop flowering yuccas. Grasshopper sparrows flit and disappear. Horned larks hunker in the dense grass. There are rock wrens, nighthawks, mourning doves and lark buntings.

Horton is recording the species and number of birds and assessing their habitat. It’s part of an effort to estimate bird population densities and evaluate whether conservation efforts are making a difference. Once grasslands are gone, he says, “it becomes harder for them to … live in those areas where they evolved and where they have been historically.”

A 2019 study found grassland bird populations had fallen 53% since 1970, compared to overall bird loss of 30%, in the continental United States and Canada. A 2022 report found that, of 24 grassland bird species, two-thirds had experienced significant population declines and eight were at a tipping point — having lost 50% or more of their breeding population and on track to lose another 50% in the next half century — putting them on a path to possible extinction.

The lesser prairie chicken is the only grassland bird federally listed as endangered, but only in part of its range. It has declined by more than 90% with an estimated remaining 2022 population of about 27,000. The Senate and House have voted to delist the bird in an effort led by Republicans who say it hinders oil and gas drilling; environmentalists hope President Joe Biden will veto the measure.

Among birds at a tipping point: Sprague’s pipit, a songbird that’s lost more than 75% of its population since 1970 and breeds only in portions of Montana, North Dakota and small patches of three Canadian provinces. The chestnut-collared longspur, which lives in the northern shortgrass prairie and sings as it flies. The Henslow’s sparrow, which barely sings at all. And the bobolink, known for its robust songs and long-distance travels to South America.

“We’re sort of banging the drum … that we’re having a massive loss of birds,” says Amy Burnett, spokeswoman for the Bird Conservancy of the Rockies. “If we don’t start turning that curve around, we won’t have the western meadowlark. We won’t have the … beautiful song of the Baird’s sparrow. Imagine if we lost that on the prairies.”

Although some grassland birds require large contiguous prairie lands, most adapted to living alongside agriculture, Cornell’s Rodewald says. That was possible because some habitat was nestled within fields or along the margins and farmers often fallowed some fields.

But more-intensive farming practices — including eliminating hedgerows and buffers, planting fewer crop types and pesticide use — have taken a toll. And climate change is bringing hotter, drier conditions that affect soil health and worsen erosion, while watering holes dry up.

So nonprofits and government agencies are working with farmers and offering incentives to improve soil, preserve grasslands and adopt bird-friendly practices, such as delaying mowing until after nesting season.

It’s a delicate balance, “because everybody needs to eat,” says Brandt Ryder, chief conservation scientist for the Bird Conservancy of the Rockies. Conservation groups are working to understand what farmers and ranchers need to be profitable while helping reverse grassland and bird decline.

“Private landowners care and are very, very good stewards of [the land] because it’s their livelihood,” he says.

Turning to technology

To help target conservation efforts, the Bird Conservancy is integrating its population and habitat data with other sources, including the U.S. Geological Survey’s long-running breeding bird survey and Cornell’s eBird sightings database.

Still, much is unknown: If birds must travel great distances to find suitable breeding habitat, does that affect breeding success? Where do they stop during migration and for how long? What’s happening on their wintering grounds, and how many birds return from their winter territory?

“Where along that full life cycle both in time and space are these birds suffering the most?” says Andy Boyce, a research ecologist at the Smithsonian’s Migratory Bird Center who studies the Sprague’s pipit. “We need to figure out a lot of this before we can even start to prioritize where conservation actually needs to take place.”

Researchers aim to find out through a growing network of radio telemetry receivers being installed across the Great Plains to help track birds from Canada to Mexico’s Chihuahuan desert.

When a bird fitted with a tiny transmitter flies within 20 kilometers (12 miles) of a receiver — mounted on towers, poles and other structures — information is stored on a computer connected to a cell network accessible to researchers.

Radio telemetry is more efficient than traditional banding that requires birds to be caught or spotted again to provide data on movements and longevity, researchers say. That’s key because many grassland birds roam the Great Plains for the best nesting habitat instead of returning to the same spot every year — a trait that evolved when wildfires and great bison herds created a constantly shifting grassland mosaic.

The receivers, part of the Motus Wildlife Tracking System managed by Birds Canada, have been installed extensively throughout Eastern and Western North America., but there were few in central grasslands until recent years, Boyce says.

Researchers are about halfway to building a network of 150 or more receivers from Canada into Mexico, says Matthew Webb, an ecologist who leads the Bird Conservancy of the Rockies’ installation efforts.

“It is extremely important to get adequate coverage,” including areas where grassland birds aren’t normally found, such as mountain passes where birdwatchers have reported sightings, he says. “We need to fill in those knowledge gaps.”

Several years ago, Baird’s sparrows, which have lost more than half of their population since 1970 and almost exclusively breed in the northern Great Plains states and Canada, suddenly showed up in Colorado and have bred there successfully since. It’s unclear, Webb says, if their range is expanding or if disturbance in their core breeding area — perhaps oil and gas drilling — forced them to turn back and use less-ideal habitat.

In South Dakota, the Cammacks allowed the bird conservancy to install the tracking tower on their ranch and another group has conducted surveys that found several tipping point species.

“Coming up from my grandfather … we do enjoy the native species, maybe more than the average rancher to a certain extent,” Reed Cammack says. “But a healthy ecosystem is a great place to raise cattle, too.”

Saving grasslands

Green prairie stretches for miles as Brian Sprenger heads out to check on his cows, many with days-old calves by their sides.

He brakes his pickup truck as an antelope bounds away and points to a handful of sharp-tailed grouse on a flat area where males gather during mating season to strut and dance.

“It’s one of the coolest things I’ve ever seen,” says Sprenger, 44, who sometimes sees two dozen or more grouse performing courtship rituals. He never saw them as a kid, when much of the rangeland near Sidney, Nebraska, was overgrazed or farmed.

But things began to change about 20 years ago, when more ranchers put land into a federal conservation program, replanted native grasses and began frequently moving their cattle to prevent overgrazing.

“We’ve noticed that as we have started allowing these rangelands to flourish … that we have seen a lot of different bird species,” says Sprenger.

Almost all of North America’s remaining prairie is on rangelands — and 90% of all grasslands are in private hands — meaning landowner cooperation is critical to stopping bird declines, scientists say. Without cattle, they say, there would be no high-quality grasslands, which require grazing and hooves on the ground to stay healthy.

Despite the progress, many land owners now must contend with fast-spreading eastern red cedar and juniper trees that are contributing to the grassland ecosystem collapse, says Dirac Twidwell, a University of Nebraska professor and rangeland ecologist.

Tree and shrub encroachment and cultivation now account for roughly the same amount of Great Plains loss every year — a combined 16,000 square kilometers (6,250 square miles), says Twidwell, a science advisor to the U.S. Department of Agriculture’s Natural Resources Conservation Service. All told, an estimated 756,000 square kilometers (292,000 square miles) have been overtaken by trees and shrubs since settlers arrived.

That leaves less land for ranching and farming — and pushes out grassland birds, which can’t adapt to the wooded environment. Shrinking rangeland now contributes to an estimated $323 million a year in potential losses to ranchers, says Twidwell.

So landowners and environment groups are cutting down trees and stepping up prescribed burns that eliminate their seeds.

“These are some of our last remaining grasslands on the planet that are largescale grasslands; that’s why you’re seeing an increased sense of urgency from bird conservation groups and the livestock industry,” Twidwell says. “All of them are saying the same thing: ‘Wait a minute, this is universally a negative.’ ”

Rancher Reed Cammack says land owners are well aware of their outsized role.

“It’s part of our responsibility … to take good care of what we have,” he says. “If there’s to be anything left for my kids’ kids to see, it’s imperative that we do something now.”



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