Recent studies show just how important prairie dogs are for ensuring nutrient cycling of soil and plants continues to keep prairie grassland ecosystems vibrant and productive. For these reasons, the study focused on 15 shortgrass prairie sites in northeast Montana. It looked at the roles that various herbivores, from prairie dogs to grasshoppers to bison to cattle, play in the nutrition of grasses and soils. Our results show a strong effect of prairie dogs on plant biomass. In addition to their role as keystone species, they are essential ecosystem engineers due to their drastic effects on the environment.
And small but mighty prairie dogs, like other native herbivores, help maintain a more productive grassland forage base. Their population in North America has completely crashed to a currently 1-2% of its historic levels prior to European settlement. Even with this reduction, they remain extremely important contributors to the cycling of nutrients. Their increasingly successful restoration and reintroduction efforts allow other species to prosper, creating a more biodiverse, thriving ecosystem and keeping the prairie vibrant and healthy.
The Role of Prairie Dogs in Ecosystem Engineering
Prairie dogs are known as ecosystem engineers, that is, they change their environment in ways that help other species thrive. By their burrowing and digging, they aerate the soil and create pockets that allow the soil to better absorb and retain water. This natural soil-building process stimulates plant production in the adjacent aquatic environment. These prairie dog towns dramatically increase plant diversity in their immediate area. This new growth in flora can help ensure the ecosystem stays balanced.
With their burrowing habits, prairie dogs help aerate the soil. They improve nutrient cycling by carrying nutrients from deep layers of the soil up to the surface. Their foraging habits aerate the soil and stimulate a richer microbial community, which is important for the decomposition of organic material. Their chewing and shredding activity makes nutrients available to other plants, helping to create a more diverse plant community.
Additionally, prairie dogs provide habitats for more than 100 different species by keeping the plains open and free from invasive grasses. These wide swaths of open space provide a refuge for many other species, increasing biodiversity. Consequently, prairie dogs are key to preserving ecological harmony in their habitats.
Impacts on Grass and Soil Nutrition
Their recent study brought attention to the extent that prairie dogs impact grass and soil nutrition. They might do it to an even greater extent than other herbivores such as bison and cattle. Large herbivores serve key functions within the food web. The reason that prairie dogs are such good nutrient cyclers is their burrowing behavior, which large animals cannot mimic.
As they dig and burrow, prairie dogs are helping improve soil fertility with their high-nitrogen waste products. This natural fertilizer encourages grasses and other vegetation to grow, enhancing the ecosystem’s biodiversity. Herbivores like bison primarily graze on existing vegetation without influencing soil structure as directly as prairie dogs do.
The research found that locations with healthy prairie dog colonies featured much higher amounts of plant biomass. Areas devoid of these charismatic little herbivores experience far less vigorous plant growth. This prolific increase in biomass is a boon to soil health. It provides a homeland to the millions of distinct wildlife species that depend on these ecosystems to thrive.
A Declining Population with Lasting Effects
Yet for all their ecological significance, prairie dog populations have suffered extreme collapses in the last century. Current estimates indicate that fewer than 1-2% of the original populations remain scattered across North America. To prairie dogs, this decline is an existential threat. It imperils the very integrity of grassland ecosystems.
This loss in prairie dog population can alter important nutrient cycling processes and decrease plant diversity. As prairie dogs disappear from their ecosystems, so too do their invaluable ecosystem engineering talents. This irreversible loss drastically increases the likelihood of less healthy, less resilient ecosystems altogether.
Conservation initiatives to safeguard prairie dog colonies are essential to maintaining the health of grasslands. Wildlife stakeholders can be appreciative of the diverse, vital role prairie dogs play as nutrient cyclers and ecosystem engineers. With this understanding, they can adopt measures that conserve prairie dogs and promote better ecosystem health overall.
