Around here, people think prairie dogs are terrible pests. Ranchers say: if we called them prairie rats instead of prairie dogs, city people wouldn’t think they were so cute. Which seems like a silly thing to say, because prairie dogs are objectively very cute and don’t have naked tails.
If the people who’d like to remove prairie dogs from the landscape could only see underground, they’d feel differently. If ranchers had x-ray vision, they’d love prairie dogs, because prairie dogs change the pathways water takes through the land. (RDennis, this post’s for you.)
When rain falls on grasslands, most of the water that falls moves back into the air through evaporation. Rain that falls on vegetation will likely evaporate. Some of the water runs overground as run-off, which will possibly join a stream or more likely evaporate. Of the water that soaks into the soil, nearly all of it is taken up by the root systems of grasses and transpired back into the air. As a rule, rain that falls on the grasslands does not soak down to the groundwater, where it could replenish local springs and streams. Unless it falls on a prairie dog town.
The soils in prairie dog towns are moister than the soils in the surrounding grasslands, and higher in organic matter. This may account for the increased populations of tunneling insects and worms that honeycomb the soil profile in a prairie dog town. Macropores are tunnels with a diameter greater than 1 millimeter, and they promote the rapid transport of water through the soil. The macropores in a prairie dog town allow rainfall that would have been lost to evaporation or run-off to trickle down to the groundwater and replenish the local vegetation.
Flury, M., and H. Flühler. 1995. Tracer characteristics of brilliant blue FCF. Soil Science Society of
Here we have a photo (properly attributed, no less) that shows grasslands soil where dyed water was poured on the surface, and then the cross section was excavated. We can see that there’s no zone of saturation moving down from the surface, like we were taught in Hydrology. Instead, the water runs down holes build by animals, worms and beetles, and through channels left by decayed roots.
By allowing prairie dogs to tunnel the grasslands, you change the pathways water takes through the land. Instead of rain disappearing through evaporation, transpiration and run-off, it settles deeply into the land where it can do some good.
If ranchers had x-ray vision, we’d see less of this
and more of this
(Prairie Dog Rapture by Anthony Falbo)
Recent Comments