- Only half of the Great Plains’ original grasslands remains intact today, the report states. Between 2009 and 2015, 53 million acres were converted to cropland every year, a two percent annual rate of loss.
- Yet little attention has been paid to the destruction of these oceans of grass, says Martha Kauffman, WWF’s managing director of the Northern Great Plains program, despite the fact that it threatens iconic species including grasslands songbirds, the monarch butterfly, and native bumble bees.
- The conversion of grasslands also compromises the ecological services provided by the Great Plains, the WWF report notes, such as the filtering of trillions of gallons of water that goes on to be used as drinking water for millions of people and helps support healthy fisheries in the Gulf of Mexico.
Temperate grassland ecosystems are being destroyed around the world, largely due to conversion to agricultural land driven by the need to provide food and fuel for the exploding human population.
A study published in August found that, despite popular belief to the contrary, grassy biomes such as grasslands and savannas harbor just as much biodiversity as rainforests — and they’re being destroyed at an even quicker pace.
This trend is especially pronounced in the Great Plains of the United States, according to a new report from the World Wildlife Fund (WWF), which found that in 2014 alone the region lost more acres of grassland than the Brazilian Amazon lost rainforest.
Only half of the Great Plains’ original grasslands remains intact today, the report states. Since 2009, 53 million acres have been converted to cropland, a two percent annual rate of loss. Some 3.7 million acres of the Great Plains were converted to cropland just last year. Nearly 13 percent of the 419 million acres that were still intact in 2009 have now been plowed over.
Yet little attention has been paid to the destruction of these oceans of grass, says Martha Kauffman, WWF’s managing director of the Northern Great Plains program, despite the fact that it threatens iconic species including grasslands songbirds, the monarch butterfly, and native bumble bees.
Populations of four key species of grassland birds — McCown’s Longspur (Rhynchophanes mccownii), the Chestnut-collared Longspur (Calcarius ornatus), the Lark Bunting (Calamospiza melanocorys), and Sprague’s Pipit (Anthus spragueii) — have declined as much as 80 percent since the 1960s due to much of their grassland habitat being destroyed, WWF found.
Meanwhile, declines of pollinators like bees and monarch butterflies have also been exacerbated by grassland loss. The range of the Rusty-patched Bumble Bee (Bombus affinis), for instance, has shrunk by as much as 87 percent over the past 15 years. WWF reports that one of every four species of North American bumble bee is now at risk of extinction, according to some estimates.
“America’s Great Plains are being plowed under at an alarming rate,” Kauffman said in a statement. “Centuries old, critical prairie habitat that’s home to amazing wildlife and strong ranching and tribal communities is rapidly being converted to cropland and most people don’t even realize it.”
The conversion of grasslands also compromises the ecological services provided by the Great Plains, the WWF report notes, such as the filtering of trillions of gallons of water that goes on to be used as drinking water for millions of people and helps support healthy fisheries in the Gulf of Mexico.
Grassland conversion also impacts the Great Plains’ ability to store carbon that would otherwise be in Earth’s atmosphere contributing to global warming. But of course, it’s not just the loss of a valuable carbon sink that is cause for alarm, as the plowing of Great Plains grasslands directly caused the release of some 3.2 billion metric tons of carbon dioxide emissions into the atmosphere between 2009 and 2015 — the equivalent of 670 million extra cars on the road, per WWF.
Grasslands are being replaced with annual crops such as wheat, alfalfa, corn, and soy, but the report says that, because much of the best cropland in the region was actually plowed-up many years ago, the conversion happening today is occurring on soils that aren’t as productive for farming.
“Today we’re growing crops on the richest agricultural lands and have been for decades,” WWF’s Kauffman said. “A high percentage of what we’re plowing up now are poor soils in landscapes that regularly experience drought. So we’re losing these valuable grasslands and the unique ecological services they provide, while getting little in return.”
WWF’s Kauffman says that the 2018 Farm Bill could be a part of the solution to this problem if it were to contain more grassland-friendly provisions. We should also be looking at policy and market drivers of grassland conversion, she argues, as well as innovative methods for producing higher crop-yields from the lands that are currently in production.
“With a growing population, the demands on the planet to produce food are increasing substantially,” Kauffman said. “Meeting those demands will require a host of solutions like climate smart agriculture, the reduction of food waste, and improved technology. But the answer isn’t and can’t just be to plow up more land.”
CITATION
- Murphy, B. P., Andersen, A. N., & Parr, C. L. (2016). The underestimated biodiversity of tropical grassy biomes. Phil. Trans. R. Soc. B, 371(1703), 20150319. doi:10.1098/rstb.2015.0319