North American Grasslands & Birds Report

Audubon's report identifies the birds most vulnerable to climate change and the places they will need as temperatures rise.

Yellow-headed Blackbird. Photo: Kristina Barker

Fewer than 40 percent of the 550 million acres of historical grasslands that once stretched from Alberta to Mexico remain today. Most of these grassland acres were converted to cropland, others to energy development or other uses. As these tallgrass, mixed grass, shortgrass prairies, and desert grasslands are lost, so are the wildlife that depend on them. 

Not surprisingly, grassland species are among the most imperiled group of birds in the United States: Total populations have declined more than 40 percent since 1966, and some species, like the Lesser Prairie-Chicken, hover at the brink of extinction. Bison, antelope, and monarch butterflies are only a few examples of the other wildlife that face a diminished future if we allow remaining grasslands to disappear or degrade. Human health and livelihoods are also entwined with the fate of grasslands. Pollinating insects thrived in fields of wildflowers and native grasses, while the deep roots of native plants trapped nutrients and water—and keep prairies resilient through natural cycles of drought, fire, grazing, and storms.

Audubon's North American Grasslands & Birds Report (2019) assessed the vulnerability of representative grassland birds and their habitat to warming global temperatures. Our findings make it clear that in addition to protecting remaining grasslands, we must also advance solutions that reduce carbon emissions, and prioritize and direct resources and other investments to the places that will support grassland birds and other wildlife into the future. 

Here is the good news: Audubon’s North American Grasslands & Birds Report identifies the birds most vulnerable to climate change, and the places, or “climate strongholds,” they will need to thrive as temperatures rise. It also points us to the sites most vulnerable to land conversion today, and highlights the specific conservation strategies that are part of Audubon’s ambitious effort to protect grassland birds and prairies. By partnering with key stakeholders in this working landscape, including farmers and ranchers, public agencies, and other stakeholders, we are finding balanced solutions that meet the needs of both birds and people. 

Our Call to Action

This report provides a comprehensive analysis of trends and threats facing North America’s grasslands and birds. Our goal is not simply to document declines, but to outline an actionable strategy for protecting and restoring these vibrant and iconic ecosystems—and safeguarding them for future generations of humans and wildlife alike. 
 
Our science investigation included an extensive review of available data on land-use trends with implications for grasslands, as well as an assessment of population and habitat trends for 19 Audubon “flagship” bird species, each selected because it is an important indicator of overall grassland ecosystem health. We collaborated with researchers at the U.S. Geological Survey to consider scenarios for future climate and land-use change, and we worked with partner organizations, such as the Playa Lakes Joint Venture, to identify strategies for grasslands conservation. Through this analysis, we were able to:
 
  • Assess the state of North American grasslands, including recent losses of acreage
  • Document declines in bird species
  • Assess vulnerability of grassland birds to the emerging threat of climate change
  • Identify and map priority grassland sites for habitat protection and restoration
  • Develop recommendations for conservation and policy interventions needed to protect these sites
     
Sand Ranch cattle graze near a pothole wetland. Cody and Deanna Sand (right) have found that helping grasslands recover benefits cows and birds. “It’s a win-win,” Cody says. Photo: Kristina Barker

The State of North American Grasslands and Birds

Tallgrass Prairie

Historically, tallgrass prairie extended from southeastern Manitoba to southeastern Texas, and east through Indiana, covering an area of 200 million acres. The wettest and most fertile and arable of grasslands, tallgrass prairie has been the most attractive for conversion to cropland. As a result, only 11 percent of the original tallgrass prairies remain—and these face a continued threat from agricultural development. Corn and soy are predominant crops, and growth in demand for ethanol crops has been a contributing factor driving conversion of land to agricultural use in recent years. 

 

Audubon Grassland Priority birds at risk in tallgrass prairie: Henslow’s Sparrow, Bobolink, Greater Prairie-Chicken, Northern Bobwhite, Vesper Sparrow, Eastern Meadowlark

 

Mixed-grass Prairie

Conversion to cropland is also the primary threat to the mixed-grass prairie found in the transition zone between the tallgrass of the eastern prairie and the shortgrass of the western Great Plains. Historically, mixed grass prairie covered an area of 140 million acres, but today only approximately 30 million acres remain. The mixed-grass prairie expanse also encompasses the Prairie Pothole Region. At the core of the Northern Great Plains, the Prairie Pothole Region gets its name from the millions of shallow depressions left behind from ancient receding glaciers amid mixed-grass prairies. These prairie potholes are wetlands rich in aquatic plants and wildlife, and support globally significant populations of breeding waterfowl, shorebirds, and grassland-obligate birds. Additionally, the Prairie Pothole Region also represents the most important monarch butterfly, honeybee, and native bee habitat in the United States. This ecologically rich region of grasslands and seasonal wetlands faces an ongoing threat of conversion to row crops, making habitat restoration and protection a critical conservation priority.  

 

Audubon Grassland Priority birds at risk in mixed-grass prairie: Upland Sandpiper, Bobolink, Baird’s Sparrow, Sprague’s Pipit, Grasshopper Sparrow, Vesper Sparrow, Lesser Prairie-Chicken, Long-billed Curlew, Northern Bobwhite, Eastern Meadowlark

 

Shortgrass Prairies

Historically, shortgrass prairie covered 265 million acres of the western Great Plains. Today, only half of this total area remains. Much drier and less fertile than the tallgrass prairies to the east, the shortgrass prairies are less arable and thus less vulnerable to conversion to cropland. However, they face growing threats from energy development, including wind and transmission lines and resulting “energy sprawl,” as well as overgrazing practices utilized by many ranchers.

 

Audubon Grassland Priority birds at risk in shortgrass prairies: Chestnut-collared Longspur, McCown’s Longspur, Mountain Plover, Horned Lark, Long-billed Curlew, Vesper Sparrow, Western Meadowlark, Ferruginous Hawk

 

 

 

Chihuahuan Grasslands

Distinguished from the three grassland types of the Great Plains by their different climate patterns and geologic history, the Chihuahuan grasslands are a region of desert grasslands in northern central Mexico, west Texas, southern New Mexico, and southern Arizona. The Chihuahuan Desert is wet compared to other warm deserts of the world, averaging 9 inches of rainfall per year.  Historically, grasslands comprised approximately 20 percent of the desert acres (around 34.5 million acres); today, nearly half of these desert grasslands have been lost, likely due to intensifying agriculture, water diversion, poor grazing practices, and energy development. Protection of this important overwintering ground is critical to the conservation of North America’s grassland birds; species overwintering in the Chihuahuan grasslands have experienced a nearly 70 percent decline. 

 

Audubon Grassland Priority birds at risk in the Chihuahuan grasslands: Chestnut-collared Longspur, McCown’s Longspur, Baird’s Sparrow, Sprague’s Pipit, Horned Lark, Grasshopper Sparrow, Mountain Plover, Vesper Sparrow, Burrowing Owl, Eastern Meadowlark, Western Meadowlark

 

Historic grassland types of North America based on mapping data from NatureServe (Comer et al. 2018) and the International Vegetation Classification and Terrestrial Ecoregions of the World (Dixon et al. 2014). Map: Daniel Huffman

Our Results

Audubon’s science team assessed the climate vulnerability of 38 grassland bird species under three scenarios representing, respectively, a 1.5, 2.0, and 3°C increase in global mean temperature. These scenarios projected the impacts of greenhouse gas emissions on both temperature and precipitation, factoring in any indirect effects on vegetation. Through this approach, we were able to estimate the percent of future range loss and gain for each bird species, and thereby assess the species’ vulnerability to climate change.

 

What we learned is alarming: For many grasslands species, climate and habitat where they are currently found will be unrecognizable to that species as the planet warms, and their ability to move elsewhere to breed, forage, and overwinter may not make up for the habitat lost due to rising temperatures. Our investigation showed that 42 percent of grassland birds are highly vulnerable to climate change under our current rate of carbon emissions (e.g. 3 °C increase in global mean temperature).

 

The good news: by curbing climate emissions, we also can reduce impacts on grassland birds. If we reduce emissions to limit global mean temperature increase to 1.5 °C, only 8 percent of grassland birds will be highly vulnerable to climate change. 

Priority Geographies for Grassland Conservation

The scale and complexity of the threats facing North America’s grasslands and the birds that depend on them demands a strategic approach designed to deliver the greatest conservation return on investment. By aggregating the best available information on bird population distributions and habitat needs, incorporating potential impacts of climate change on critical habitat, and factoring in projected future land use, we identified high priority grasslands that are important for birds now and likely to remain so in the future. We combined these findings with Grassland Priority/Potential Conservation Areas identified in 2005 and 2018, which did not factor in climate change. The resulting consensus priority conservation areas are illustrated on the map below. These are the places where grassland conservation action and investment is likely to yield the greatest return in protection of birds and the places they need, for today and tomorrow. 

 

  1. Climate strongholds: the places that can continue to provide quality habitat for birds as global temperatures rise. These are located across the southern Great Plains of New Mexico, Texas, the Oklahoma Panhandle; the Chihuahuan desert; and the northern Great Plains of North and South Dakota, Nebraska, Montana, Wyoming, Alberta, Saskatchewan, and Manitoba.

  2. Existing Grassland Priority/Potential Conservation Areas, which include the Flint Hills of Kansas and Oklahoma and represent regional and tri-national priorities identified in this report, as well as in previous conservation planning efforts.

  3. Vulnerable grassland priorities distributed across the Gulf Coast Prairie, Texas Blackland Prairie, the Chihuahuan desert, large portions of the eastern-central Plains, and the Prairie Pothole region and surrounding areas. Increasing pressure from competing land uses in the eastern half of the central grasslands, due to their higher precipitation levels and suitability for irrigated row crops, makes this region extremely vulnerable to land conversion. Urgent conservation action is required to protect or restore any unprotected tall- and mixed-grass prairie that remains.
     
A fence line bordering the property of rancher Nancy Ranney (left) shows how rotational grazing spurs native grasses and wildflowers, while ungrazed land boasts far less diversity. Photo: Minesh Bacrania

Four Components of Audubon's Grassland Strategy

Partnering with Private Land Managers

With 84 percent of central grasslands in the United States in private ownership, collaboration with ranchers and farmers is critical to conservation success. That is why Audubon works closely with private land managers, providing technical assistance as they incorporate bird-friendly practices into their operations and improve overall ecosystem health. Implementation of these best management practices enables domestic livestock to mimic the movements and pressure of historical grazers. This ensures that, like the bison of yore, grazing beef cattle improve soil health and help to create the plant diversity and structure of native prairie habitat that grassland birds prefer. 

 

Audubon’s conservation team develops Habitat Management Plans that address site-specific habitat and bird conservation opportunities on ranches participating in one of our programs. Desired outcomes are guided by the habitat needs of a region-specific set of priority/target grassland bird species. In addition to habitat management practices, the protocols also include a standardized set of criteria related to forage consumption, animal health & welfare, and environmental sustainability. Findings from our grassland report will help Audubon prioritize engagement with ranches in grassland priority geographies to protect existing grassland strongholds and vulnerable areas. The result: more resilient and productive working lands and better habitat for birds. 

 

Conservation Incentives and Easements

Audubon will conserve 1 million acres of critically endangered grassland and associated wetland habitat by 2022 through a matrix of strategic grassland enhancement, restoration, and protection using conservation incentives and easements. We will focus on conservation efforts to support endangered and threatened grassland-dependent species such as Greater Prairie-Chicken and Western Meadowlark, as well as wetland-dependent species such as Whooping Crane, Sandhill Crane, Northern Pintail, and Black Tern.

 

In North Dakota, in the heart of the Prairie Pothole Region, Audubon is piloting cost-share opportunities with private landowners to provide grazing infrastructure (perimeter and cross fencing, water wells, pipelines, etc.), invasive species removal/control, and prairie restoration/reconstruction. Program enrollment requires landowners to conserve their grasslands for up to ten years, depending on the specific conservation practices implemented. Audubon staff work with landowners to develop and implement site-specific Habitat Management Plans that include plans for monitoring and assessing the impact of the applied land management practices on birds and vegetation. We are now expanding this unique grassland management assistance program into other parts of the Northern Great Plains.

 

Market-based Incentives for Grassland Conservation

Audubon’s Conservation Ranching Initiative uses an innovative, market-based approach to incentivize bird-friendly livestock management practices. These regenerative grazing practices improve soil health, diversify habitat structure, and ensure environmental sustainability that benefits pollinators and other grassland wildlife. Ranchers who comply with Audubon-approved habitat management plans earn the right to use the “Grazed on Audubon Certified Bird Friendly Land” certification mark in product promotion, attracting conservation-conscious consumers and supporting premium pricing. Currently, nearly 2 million acres and 65 ranches across 11 states are certified through the initiative, with more in the pipeline. Products with this certification are available from 26 retailers and 12 restaurants across 7 states, and 11 companies that sell online. Audubon’s goal is to have 2.5 million acres enrolled by the end of 2020. It is a win-win approach that strengthens the economic vitality of rural communities and builds healthy functioning grassland ecosystems.  

 

Carbon sequestration represents another opportunity for ranchers to accrue both economic and ecological benefits from regenerative grazing practices. While the agricultural sector represents 9 percent of U.S. greenhouse gas emissions, there is growing evidence that soils on agricultural lands, especially grasslands, can store a considerable amount of carbon dioxide. Markets are now emerging that pay ranchers to preserve and manage their grasslands and to lock carbon into the soil. While this is a fledgling industry, methods and protocols have been developed to measure carbon sequestration rates, generate credits and verify results, and transactions have occurred whereby landowners sell carbon sequestration credits in voluntary markets. The management practices that sequester carbon into soils on ranches also foster healthy habitats for wildlife, and more nutrient-rich food for livestock. Audubon is exploring how it can best facilitate this market and provide landowners with an additional financial incentive that produces results beneficial to protecting grasslands.

 

 

Federal and State Policies

Conversion to row crop agriculture, urban development, oil and gas development, and fire suppression and subsequent woody encroachment are the primary sources of loss of native prairie landscapes. In order to limit future grassland conversion, Audubon will pursue a proactive policy strategy at the federal and state levels that incentivizes grassland conservation and discourages excessive conversion practices. The following are some key policy opportunities:

 

Farm Bill
What happens on our nation’s 914 million acres of farms and ranches has significant implications for North American birds and other wildlife. The largest federal funding source for conservation on these lands is the Farm Bill, which provides agricultural producers and private landowners with billions of dollars in assistance for adopting conservation practices in their operations. Farm Bill programs are critical for birds and other wildlife—in 2015 alone, they improved almost 9 million acres of wildlife habitat. Audubon helped to secure passage of the 2018 Farm Bill reauthorization, expanding funding and access to programs benefiting birds and other wildlife.  Ensuring continued authorization and working with private landowners on opportunities to participate in these programs are ongoing priorities for Audubon.

 

 

State Wildlife Action Plans
State Wildlife Action Plans identify imperiled species in the state and describes actions to assist in their recovery and protection. The State Wildlife Grants Program is currently the main source of federal funding for states and territories as they implement these plans; however, it currently provides only $70 million for all 50 states and territories, not nearly enough to enable recover and protection of imperiled species. Audubon is working to help secure funding for State Wildlife Action Plans across the Great Plains—an essential step for the birds and people who depend on this important landscape.