Sul Ross researchers propose reintroducing prairie dog

ALPINE A proposed research study by Sul Ross State University would reintroduce native black-tailed prairie dogs to a family ranch in southern Brewster County.

Once thought to be a detriment to grazing land because of their impact on the vegetative structure, prairie dogs are now viewed in a more positive light.

"Many people believe that prairie dogs compete with livestock because they eat grass," said Bonnie Warnock, assistant professor of Natural Resource Managment. "As the science of range management has developed, ranchers have gained a better understanding of grazing land dynamics. There is a mounting body of evidence that many of our previous beliefs about prairie dogs were erroneous which has contributed to changes in landowner viewpoints."

These burrowing, colonial herbivores play three major roles in grassland ecosystems - they are important prey species, they create burrows and they graze vegetation. Prairie dogs serve as a prey base for many birds and mammals, including ferruginous hawks, Harris hawks, golden eagles, red tail hawks, badgers, coyotes and fox.

Burrows provide shelter and nesting sites for other species, such as the burrowing owl and kit fox. The act of burrowing benefits the soil. It redistributes nutrients and minerals, improves infiltration and moisture retention, and mixes subsoil and topsoil.

"Prairie dogs can overgraze an area just as any other herbivore, which can result in less livestock forage," Warnock said. "However, prairie dogs can be managed like other wildlife species and livestock. Experience and studies have demonstrated that we can balance wildlife and livestock populations through proper management and increase the overall revenue for the ranch, the diversity of species that the grassland supports, and enhance the overall health of rangeland ecosystems."

According to research studies, at least 146 associated species benefit from prairie dog colony sites: Nine species directly depend on them for survival and reproduction, 20 species opportunistically benefit, and 117 species have a history that suggests a benefit from associating with prairie dogs.

"If the population is managed, prairie dogs reduce the overall height of grass in an area but do not kill the grass plants; much like mowing a lawn makes it more healthy," Warnock said. In addition to changing grass height, prairie dogs also enhance digestibility, nutritional value, and productivity of grasses and forbs within the town area. The decreased stature of the grass and the enhanced quality attract other grazers such as pronghorn antelope.

The short vegetation also attracts other species that prefer to forage in more open terrain, such as mountain plovers and blue quail. The continuous clipping of plants also alters the types of plants in an area potentially removing and controlling woody plants such as mesquite. This is the focus of the proposed research study.

"As a member of a long-time ranching family in Brewster and Pecos counties, I have had the opportunity to experience ranching with prairie dogs on a first-hand basis," said Warnock. "The ranch where I grew up always had several colonies of prairie dogs. Rather than trying to eradicate them, my father saw them as a source of revenue and recreation on the ranch. Hunting was managed and through this, population numbers were kept in check, and the towns did not spread across the entire ranch, even though there was plenty of additional suitable habitat.

"Our cattle used the area year-long for grazing and loafing, and it was the preferred grazing area in the spring because the grass in the prairie dog towns greened up first. Despite the pervasive notion that cattle and horses can break their legs in the holes, I never experienced that misfortune and have not known anyone that it has happened to. The stories I was told always began ‘a friend my friend knew...,' but I am unaware of a documented case of having to put an animal down because it injured itself in a prairie dog burrow."

The most serious concern associated with prairie dogs, as with any rodent, is disease. Fleas are the vector that spread sylvatic plague. The plague kills prairie dogs and can devastate a colony. If someone is in close contact with prairie dogs in an outbreak, the fleas could spread the disease to humans.

When prairie dogs are moved they must be quarantined and dusted with flea powder to insure no disease is spread from one colony to another. Studies have shown that the Trans Pecos area has the lowest potential for plague in prairie dogs within Texas.

The potential reintroduction that has been discussed on the Midland news involving Sul Ross and the City of Midland is in early planning stages and is still just a possibility. If the project reaches fruition, the vagaries of the reintroduction process are still great and the possibility of failure is high. The reintroduction would take place on private land at the request of, and with the full cooperation of the landowner. "The proposed reintroduction would occur in a small isolated area to ensure no spread to neighboring properties. The colony, if it becomes established, would be monitored to study the impact prairie dogs have on mesquite and mesquite seedlings in restored desert grassland," Warnock said.

"A study following a prairie dog reintroduction is a natural outgrowth of successful existing grassland restoration occurring in this part of the Big Bend Region and is a natural fit with the type of research Sul Ross State University undertakes to enhance the productivity and sustainability of our ranching communities."

For more information, Warnock, (432) 837-8706.