Recovery of Endangered Species is Being Helped - by Buffalos !

​Researchers at Kansas State University have discovered a way to help bring back the endangered prairie grass ecosystem using a tool not found in laboratories - buffalos. 

Prior to the displacement of native Americans by European settlers, a vast area of land stretching from Texas to southern Canada was covered with tallgrass prairies, a diverse mix of waist-high grasses and flowering bushes. These lands were also home to an estimated 30 – 60 million buffalos (aka American bison). Both the plants and the buffalo numbers crashed after the US government supported the eradication of buffalo in an attempt to cut off the food supply of native Americans who had previously occupied those areas. By the 1890’s, buffalo became an endangered species with only a few hundred remaining, and tallgrass prairie ecosystems were reduced to only 4% of their previous size. 

The research is being carried out at the Konza Prairie Biological Station, a 28 km2 tallgrass prairie reserve jointly owned by KSU and the Nature Conservancy. The question under study is how important buffalos are for the maintenance of a healthy, diverse ecosystem. Turns out, they are very important. 

Researchers compared plots of tallgrass prairie that had no buffalos to plots that had buffalos and to plots that grazed cattle. Over time, the plot without buffalos or cattle became dominated by a few species of tall grasses and had the least biodiversity. The plot that was grazed cattle had an increase of 30% in the number of native plant species that were growing there. The plot with buffalos showed the most diversity with an impressive increase of 85% in the number of native species compared to the plot without grazing animals. 

Buffalos were found to have a number of biodiversity increasing effects on the ecosystem. By eating the tall grasses other plant species were able to increase their populations. The buffalo’s dung helped fertilize the soil and their hooves help mix the dung into the soil along with air improving conditions for plants. With an increase in plant biodiversity came an increase in animals that found food and hiding places within the plant-enriched land. Even the buffalo’s fur turned out to be valuable as it was picked up by birds and used for nests when the buffalo were shedding. 

The observed affect is called “keystone herbivory” which refers to how a large herbivore has a far-reaching impact on other species that they share the ecosystem with. 
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The research reveals a general rule regarding human impact on biodiversity. When we go into an ecosystem and remove a species for our purposes, other species also disappear in response to the disruption. So, to protect existing biodiversity it is best to leave ecosystems intact and extract resources we made need in as gentle a method as possible. 

You can learn more about this topic by visiting National Geographic

To learn more about the history of buffalo eradication in the US go here

​​By Rick Martin

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