Grasslands are tough. They can survive extremes, from heatwaves and cold snaps to torrential downpours and droughts. They require turbulence. For millennia wildfires enhanced prairie soil and ensured grass’s dominance by burning back woody shrubs and saplings. Bison followed the fires to graze on tender, new growth of grasses and sedges; as they fed, their hooves aerated and manure fertilized the soil, giving rise to abundant wildflowers. The combined forces shaped the Great Plains, a mosaic of hundreds of grass, wildflower, and sedge species at various stages of growth spanning 550 million acres. The patchwork of habitats supports diverse insects, dozens of songbird species, and myriad mammals.
Despite their resilience, barely one-third of central North America’s historical grasslands persist today. Farming and development have razed 90 percent of its tallgrass prairie, three-quarters of its mixed prairie, and half of its shortgrass prairie. “It actually dwarfs what we’re seeing in the rainforest in the sheer scale and size and intensity of the crisis,” says Marshall Johnson, executive director of Audubon Dakota. That destruction has in turn hit grassland birds, which have declined by more than 40 percent since the 1960s; some species have seen even steeper declines.
Audubon’s North American Grasslands & Birds Report, published this summer, highlights the added perils that climate change poses to the Great Plains’ avian denizens. Heat, erratic rainfall, and drought may make significant areas inhospitable to certain species within decades. Audubon scientists built climate models that incorporate temperature, precipitation, vegetation, and other characteristics of the habitats 38 grassland-bird species occupy. They found that 16 species will likely see most of their current range become uninhabitable if Earth’s temperature rises by 3 degrees Celsius; if we limit warming to 1.5 degrees, the number facing this threat drops to just three.
The data also point to places, called “strongholds,” that will provide crucial habitat for grassland birds through the coming changes—if those lands are managed optimally. With more than 80 percent of U.S. grasslands privately owned, ranchers are key to protecting those critical areas. “Grazing is probably the most important tool for manipulating good grassland-bird habitat,” says Chris Wilson, director of Audubon’s Conservation Ranching Program. Across the Great Plains, conservationists are working with ranchers to shore up these strongholds and safeguard birds’ survival.
Read more: audubon.org
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