Restoring Mule Deer Habitat
Cheatgrass has become dominant on the west side of the Kaibab Plateau, where the Bridger Knolls Complex Fire burned 50,000 acres in 1996. The Forest Service and the Arizona Game and Fish Department are implementing a 30,000 acre mule deer habitat restoration project that entails restoring native grasses and shrubs, while reducing cheatgrass cover. We are assisting them in these efforts by collecting and planting native seeds and providing capacity for monitoring the success of these treatments over time.
In June, 1996, the Bridger Complex Fire burned nearly 50,000 acres of grass-, shrub-, and woodland on the Kaibab Plateau’s west side – an area that provides critical winter range habitat for the Kaibab mule deer herd. For more than five years, the area responded to the burn in a relatively natural manner. A combination of climate events in 2002 and 2003, however, generated an explosion of cheatgrass across vast portions of the burn area. Cheatgrass now dominates tens of thousands of acres across the Bridger Complex burn area. Once cheatgrass comes to dominate an area, it is impossible to eradicate, and extremely difficult to control. Once an area becomes invaded, cheatgrass crowds out most other native plant species, and changes the areas fire cycle dramatically (cheatgrass “cures” during fire season, is very flammable, and responds positively to fire – thus creating a frequent, flashy fire cycle that perpetuates cheatgrass in any particular area).
Given the west side’s critical importance for the Kaibab Mule deer herd, the Arizona Game and Fish Department initiated in 2006 a 10-year effort to restore habitat conditions across nearly 30,000 acres of critical winter range habitat that had not yet become dominated by cheatgrass. Habitat restoration work involves re-seeding of key shrub species lost since the burn. In arid environments such as this, re-seeding requires relatively intense seeding and seedbed preparation actions accomplished through the use of mechanized mechanical seeders.
While mechanized re-seeding is one of the only methods shown to re-establish native plant species in arid environments across the Arizona Strip, resulting soil disturbance can, in and of itself, facilitate invasion by invasive, non-native plant species, including cheatgrass. As such, the work proposed by AGFD has the potential to positively enhance conditions across the project area, but also has significant unintended and negative consequence potential.
In 2006, we initiated a partnership with the Arizona Game and Fish Department and the U.S. Forest Service that is centered around increasing the efficiency and effectiveness of habitat restoration on the west side of the Kaibab Plateau. Our contribution includes assisting with on-the-ground restoration work, as well as research, monitoring, and adaptive management. Since then, we have been providing assistance to AGFD and U.S.F.S. as described below:
- Collection and integration of monitoring data - In 2007, we installed over 250 photo plot locations across the project area that will enable us to visually track progress toward our restoration objectives. We also installed 70 ground plots, where the abundance of key shrub species and cheatgrass was measured, which will allow us to monitor the effectiveness of seeding treatments in subsequent years.
- Integration of predictive cheatgrass invasion models into project planning - Cheatgrass occurrence and spread maps will be very important in guiding ongoing habitat enhancement work on the west side. We are working with the Arizona Game and Fish Department and U.S. Forest Service to identify areas of greatest risk with respect to cheatgrass invasion, and take the lead in implementing monitoring in these high risk areas.
- Volunteer assistance in local native seed collection and reseeding of native species – Grand Canyon Trust volunteers are assisting AZ Game and Fish staff in reseeding native grasses and collecting native seeds across the west side for use in ongoing restoration activities. By supplementing purchased seed with locally adapted genotypes, we hope to have an increased likelihood of seed viability and greater success in our restoration efforts.
Between the Bridger Knoll Fire of 1996 and the Warm Fire of 2006, intense wildfires have affected more than 120,000 acres across the Kaibab National Forest in just over a decade. Wildlife habitat restoration efforts in each of the areas burned will have a significant effect on long-term habitat viability for scores of species, including the world-renowned Kaibab mule deer herd. They will also largely determine whether intensely burned areas regain some semblance of a natural community, or are invaded and dominated by invasive, non-native species – especially cheatgrass. Our collaborative work with the U.S. Forest Service, Arizona Game and Fish Department, Northern Arizona University, and others will simultaneously and significantly build the “labor pool” available for labor intensive restoration projects, will build critically essential monitoring capacities for these projects, and will leverage project-level and landscape-scale data collected to better inform future wildlife habitat management efforts across the Plateau. As such, we hope to enhance state and federal agencies’ efforts to work harder and smarter across the Plateau – increasing acres treated and effectiveness of treatments.