Wildlife Impacts
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Weeds and wildlife

Drawing of a badgerThe Great Basin is home to many diverse species of wildlife, including black-tailed jackrabbits, sagebrush voles, kangaroo rats, pygmy rabbits, sage grouse, pronghorn, elk, mule deer, coyotes, and mountain lions. The Snake River Birds of Prey National Conservation Area in southwest Idaho hosts the nation’s largest population of nesting raptors, including golden eagles, ferruginous hawks and red-tailed hawks, and one of the largest populations of badgers in the world.Drawing of a sagebrush vole

While some species of wildlife can utilize invasive weeds to varying degrees, these weeds replace more preferred plants. Some create dense monocultures that many animals don’t utilize. Invaders, like cheatgrass, alter the natural fire regime. All invasive weeds reduce native plant populations, altering the habitat of many animal species.Picture of a male sagegrouse

Few animals are as dependant on a particular habitat as the sage grouse. All requirements for breeding, nesting, rearing, and feeding are located in sagebrush-dominated communities. Cheatgrass-fueled fires remove sagebrush and many associated plant species. This eliminates quality cover for nesting, and hiding from predators. Adult sage grouse rely heavily on sagebrush for food during winter months. An understory of forbs and grasses is vital for chick rearing. Hens are healthier and chick survival is higher when buds and new leaves from forbs are abundant in the spring. The sage grouse is at risk of being listed as an endangered species.

Group of mule deer bucks

Currently, mule deer are the only large ungulates in the western United States with a declining population. In the Great Basin, this decline is linked to weed invasion. Cheatgrass-fueled fires remove critical browse species and shrink vital winter range. Mule deer move from higher elevations down to sagebrush-dominated sites to survive the winter months. Without nutritious forage that stands taller than snow depth, many deer die and fewer healthy fawns are born in the spring.

Drawing of a pygmy rabbitOther animals impacted by sagebrush loss include the Brewer’s sparrow, pygmy rabbit, and the sagebrush lizard. Drawing of a sagebrush lizardThey rely heavily on a sagebrush dominated habitat. Brewer’s sparrows nest in the shrubs. Pygmy rabbits need sagebrush to hide from predators. Sagebrush lizards prefer to eat insects that live in the sagebrush canopy, and are often seen on tops of these shrubs.

Picture of a yellow starthistle infestation

Perennial pepperweed, whitetop, knapweed, and yellow starthistle stands grow very thick, making areas traditionally used by nesting waterfowl and upland game-birds unfavorable.

-Badger: Sagebrush Clips © 2005 Zackery Zdinak.
-Sagebrush vole: Sagebrush Clips © 2005 Zackery Zdinak.
-Sagegrouse: Gary Kramer, U.S. Fish and Wildlife Service.
-Mule deer: Public domain.
-Pygmy rabbit: Sagebrush Clips © 2005 Zackery Zdinak.
-Sagebrush lizard: Sagebrush Clips © 2005 Zackery Zdinak.
-Yellow starthistle: J.S. Peterson @ USDA-NRCS PLANTS Database.

Text references:
-Crawford, J.A., and M.A. Gregg. 2001. Survival of sage grouse chicks in the northern Great Basin. 2000 Annual Report. Bureau of Land Management, Portland, Oregon, USA.
-Entwistle, P.G., A.M. DeBolt, J.H. Kaltenecker, and K. Steenhof, compilers. 2000. Proceedings: Sagebrush Steppe Ecosystems Symposium. Bureau of Land Management Publication No. BLM/ID/PT-001001+1150,Boise, Idaho, USA.
-Howard, Janet L. 1999. Artemisia tridentata ssp. wyomingensis In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: (http://www.fs.fed.us/database/feis/, 26 September 2006).
-Pellant,M. 1996. Cheatgrass: the invader that won the west. Unpublished report. On file with: U.S. Department of Agriculture, Forest Service; U.S. Department of Interior, Bureau of Land Management; Interior Columbia Basin Ecosystem Management Project, 112 E. Poplar, Walla Walla, A 99362.