How bison are restoring US grasslands

November 17, 2023 7:45 PM

How bison are restoring US grasslands. Plains bison co-evolved with the short-grass prairie. In the 12,000 years since the end of the Pleistocene, they have proven themselves to be potent ecosystem engineers. An adult bison eats about 25lb (11kg) of grass a day. The grasses adapted to their foraging. Vegetation across the plains uses the nutrients in their dung. Birds pluck their fur from bushes to insulate their nests. Bison also shape the land literally. They roll in the dust and create indentations known as "wallows" that hold water after rainstorms. After the bison move on, insects flourish in these pools and become a feast for birds and small mammals. Pronghorn antelope survive by following their tracks through deep winter snows.
posted by chariot pulled by cassowaries (16 comments total)

Thank you, chariot pulled by cassowaries.

Danny Kinka, the non-profit's wildlife restoration manager, drives me to see an example of a creek in full-blown, bison-assisted recovery. [...] Kinka explains how the bison had set the stage for beavers – nature's other great restorationist – to help bring the landscape back to health. The abundance of new growth made possible by the bison gave beavers the building material they needed. We walk across a beaver dam made entirely of mud and cattails. Over the years to come, the flooding created by the dams will cause cottonwood seeds buried in the streambanks to sprout, leading to the regrowth of trees, says Kinka. As more shrubs and trees return, more beavers will move in and build more dams, he adds. [...]

What excites Kinka about the recovery here is its simplicity. "We didn't go down there, we didn't reintroduce beavers, we didn't build BDAs [Beaver Dam Analogues]. We didn't do anything," he tells me. "We just put bison here. This is resilience that is inherent in the system. It just needed a little bit of a break from grazing to be able to do this all on its own." What's more, the creek is still improving, he says. "Every year the creek gets a little wider, a little more meandery, a little more like a pool and less like a trench."
posted by Iris Gambol at 8:21 PM on November 17, 2023 [13 favorites]

What an fantastic story.

There was a lot of fascinating information in 1491, but the fact that really surprised and stuck with me was that there had been bison much further east than I was aware - past the Appalachians, in populations that Native Americans kept in balance with managed forests, for food and other products. Since it seems pretty unlikely bringing them back east would ever work out ("Little of the most important bison habitats remain east of the Mississippi"), I hope they're wildly successful out west.
posted by EvaDestruction at 9:05 PM on November 17, 2023 [3 favorites]

"Vegetation across the plains uses the nutrients in their dung. They roll in the dust and create indentations known as "wallows" that hold water after rainstorms."

Yet, when I do this, I get the side-eye.
posted by PareidoliaticBoy at 9:09 PM on November 17, 2023 [13 favorites]

I live where there used to be a lot of bison, now it is mostly corn and soybeans. Most land that is too steep or wet to grow row crops is used as cattle pasture. These pastures are almost always in small valleys and around streams and wetlands. The pastures are sprayed with herbicide to keep down the thistles and other plants that the cattle can't eat, and it is sprayed with pesticides to kill gnats and mosquitos that come from the streams and wetlands in the pasture. These pastures usually have very little plant diversity, mainly introduced grass species, and they are usually overgrazed and eroding with compacted soils and little vegetation next to the water. It is amazing to see how productive a diverse properly managed grassland and restored prairie can be compared to most pastures. However, most of the planted prairie and grassland that is not used as pasture is not grazed (or burned or mowed) at all, and it fills with thatch and eventually shrubs and trees and the diversity and productivity declines. There needs to be a way to move the cattle more frequently over larger areas to help provide the kind of light impact that helps prairie be productive and diverse while preventing the intense impact that causes decline in grassland and wetland and riparian areas. Or just turn it all back to prairie and bring back the bison, which is my preference.. Bison tastes great and is healthier than beef, and a little goes a long way in a meal.
posted by GiantSlug at 12:19 AM on November 18, 2023 [9 favorites]

This is an excellent article. After a couple decades studying restoration done by people, I am completely committed to the idea that we should get out of the way and let the natural processes work. And I of course always appreciate a shout-out to the beavers.

Thanks, chariot pulled by cassowaries, for your awesome nature posts!
posted by hydropsyche at 5:06 AM on November 18, 2023 [3 favorites]

This is an excellent article. After a couple decades studying restoration done by people, I am completely committed to the idea that we should get out of the way and let the natural processes work. And I of course always appreciate a shout-out to the beavers.

I'd agree, but with a caveat: You have to get out of the way in the right way. Setting the stage for restoration is not as simple as walking away and doing nothing -- that is usually a recipe to have a thick stand of weeds and other less desirable plants. It takes understanding the environment sufficiently to know that e.g., you have sufficient resources there for the early groups of bison and sufficient connectivity to other habitats for other desirable plant and animal species to move in. (Like, do you need to give the site a boost with early seral plant species, or is it adequate already and with good seed banks for what will follow the disturbance?)

It's still a human-intensive project, but you aren't out there with a bulldozer trying to emulate beaver dam configurations. Instead you are setting the stage for beaver reintroduction (meaning connectivity so they can get there, but also a project area located where beaver dams won't cause harm and damage to critical infrastructure. It's tricky work and actually a lot harder to pull off than a typical more heavy-handed, engineering-heavy restoration project.
posted by Dip Flash at 5:34 AM on November 18, 2023 [7 favorites]

I love stories about bison. What an animal. And I love the teamup of bison and beavers!

This joke makes me laugh every time I think about it and is not my own, but I can't remember where I first saw it:

[sound of trickling water]

Beaver: absolutely fucking not.
posted by snwod at 6:08 AM on November 18, 2023 [8 favorites]

I've mentioned this before, but we have a bison preserve quite nearby, and the local paper once ran a headline reading

BISON DOING FINE; SOME VISITORS NEED EDUCATING

which is probably just as true today as it was seven years ago
posted by Wolfdog at 6:11 AM on November 18, 2023 [8 favorites]

It's worth noting that there is a lot of opposition to the American Prairie Reserve. Many ranchers see the bison as a threat, both in terms of taking "their"* rangeland and the bison being a disease vector (brucellosis). It doesn't help that APR gets most of its funding from outside the region.

*I use the scare quotes because grazing is often on BLM land rather than land owned by the ranchers. But that a function of how homesteading worked and what the land can support and other issues.
posted by CheeseDigestsAll at 6:52 AM on November 18, 2023 [4 favorites]

This is a good follow up to the recent Ken Burns doc The American Buffalo on PBS. An amazing and gut-wrenching lesson on the buffalo history and the relationship of the land, animals, and human activity. Learning more about the restoration efforts and the result of nature doing it's thing is fascinating.

BISON DOING FINE; SOME VISITORS NEED EDUCATING

which is probably just as true today as it was seven years ago

Can confirm, still true given interactions between humans and animals this year especially in the National Parks.
posted by inkonmylar at 8:15 AM on November 18, 2023 [1 favorite]

The more I learn about the destruction of the natural systems that has happened over centuries, the more I feel it acutely as a terrible loss.

Stories like this are needed to show the amazing processes managed by the natural world.
posted by glaucon at 8:27 AM on November 18, 2023 [1 favorite]

Bison bison Bison bison bison bison Bison bison.
posted by Cardinal Fang at 11:12 AM on November 18, 2023 [3 favorites]

I am so excited by about prairie restoration. Every acre of land that we grow ethanol corn on should be returned to prairie and managed with bison or cattle. It’s just such a food productive ecosystem - waterfowl, wild rice, bison/cattle, deer, etc - that also stores buckets of carbon and is extraordinarily beautiful to boot.
posted by congen at 2:21 PM on November 18, 2023 [6 favorites]

The grasses adapted to their foraging

They roll in the dust and create indentations known as "wallows" that hold water after rainstorms

Makes you wonder what the natural Prarie ecosystem would look like without bison engineering it for thier own benefit.
posted by B3taCatScan at 6:55 PM on November 18, 2023

Pronghorn antelope survive by following their tracks through deep winter snows.

Oh, man, pronghorn antelopes: I grew up in a small town in Idaho and my mother was from an even smaller town just outside of Lincoln, Kansas. This was well before Amtrak. My father was a doctor who contracted with Union Pacific, and an ancillary benefit was a deep discount on the price of our train tickets to visit the maternal grandparents in Kansas. We rode there more than once.There were two big events along the trip. One was changing trains in Denver, where the station and its rail yard were enormous to our eyes. Everything seemed to go on and on forever, coming or going. But best of all before that was hours before Denver seeing every so often three or four pronghorn antelopes striking noble poses in the Wyoming dawn's early light. Standing with their forelegs up atop knoll or boulder, heads held high, scannng in every direction, those were majestic profiles indeed. It made the heart beat faster to see them.
posted by y2karl at 1:01 PM on November 20, 2023 [2 favorites]

Mod note: [btw, this post has been added to the sidebar and Best Of blog]
posted by taz (staff) at 2:37 AM on November 25, 2023