Adaptive Management

The federally-listed threatened humpback chub is a native fish of the Colorado River. Despite the environmental changes to the river following the construction of Glen Canyon Dam, humpback chub persists alongside nonnative species, including rainbow trout. The pre-dam Colorado River experienced seasonal variation in temperature and discharge. Seasonal flooding resulted in sediments carried...

Aquatic insects are important components of riverine foodwebs as they are prey for fish, birds, bats, lizards, and spiders. The closure of Glen Canyon Dam in 1963 fundamentally altered the hydrology, water temperature, and turbidity of the Colorado River through Grand Canyon. These changes, along with competition with invasive species and limited food availability have led to the decline and...

As restoration needs for natural landscapes grow due to higher frequency and/or intensity disturbances, pressure from invasive species, and impacts resulting from changing climates, considerable time and resources are being invested to guide the development and deployment of native plant materials (NPMs). Across lower elevations of the Colorado Plateau, a region composed primarily of public land...

In the western United States (U.S.), there are many regionally restricted, rare species resulting from complex demographic and ecological processes through time. In addition to the inherent risks associated with being rare (i.e., having few individuals spread over a limited area that could be disproportionately affected by chance events), anthropogenic disturbances are increasing in magnitude...

Research using genetic principles, methods, and data provides critical information for restoration and conservation science. Genetic research may rely only upon genomic sequencing techniques, which generate abundant, genome-wide DNA sequences that can provide a glimpse into a species’ evolutionary history and adaptations. Genetic research may also look at an organism’s physical traits to...

The Grand Canyon Monitoring and Research Center currently functions under a Triennial Work Plan (TWP) which is thoroughly reviewed and vetted both internally within the Center and through the GCDAMP Technical Work Group (TWG) and the Adaptive Management Work Group (AMWG). These advisory panels have been a part of the Glen Canyon Dam adaptive management process since the inception of the GCDAMP...

Drylands (sometimes called ‘deserts’ or ‘arid and semi-arid' ecosystems) are defined by water scarcity. Understanding how land-use activities may effect dryland ecosystems and dryland ecological processes is a high priority for land conservation and management. Grazing by domestic livestock (typically cattle but also sheep and goats) is the most widespread land-use in drylands globally and a large...

Sediment controls the physical habitat of river ecosystems. Changes in the amount and areal distribution of different sediment types cause changes in river-channel form and river habitat. The amount and type of sediment suspended in the water column determines water clarity. Understanding sediment transport and the conditions under which sediment is deposited or eroded from the various...

Reclamation on lands impacted by energy development is complicated and extremely challenging in arid environments due to unstable soils, exotic species, and low and variable precipitation. The reclamation tactics employed by energy operators vary widely and outcomes can differ across plant communities and soil types. In order to address the knowledge gaps regarding how to successfully and...

River channels and their adjacent floodplains are ever evolving in form and composition in response to changing patterns of streamflow, the quantity and size of supplied sediment, and feedbacks with the riparian and aquatic ecosystems. Changes in channel form affect aquatic and riparian habitats, which are important for plants, animals, and insects. Erosion and deposition of river channels and...

The sandbars exposed along the shoreline of the Colorado River represent only a small fraction of the sand deposits in Grand Canyon, most of which are on the bed of the river in eddies and the channel. Current management practice includes efforts to maintain and build sandbars by releasing high flows from Glen Canyon Dam that are timed to coincide with periods of fine-sediment supply from...

Sandbars have been used as campsites by river runners and hikers since the first expeditions to the region more than 100 years ago. Sandbar campsites continue to be an important part of the recreational experience for the more than 25,000 hikers and river runners that visit the Colorado River corridor each year. Because the Colorado River is dominated by bedrock cliffs and steep talus slopes...