Non-native or Invasive Species

The Colorado River and its major tributaries provide a crucial water supply for more than 40 million people in the American Southwest and in California. This water supply is primarily used in irrigated agriculture but also provides essential drinking water to many large metropolitan areas. Hydropower is also produced at many of the large dams on the river. River flows have declined...

The sagebrush ecosystem is home to diverse wildlife, including big-game and Greater sage-grouse. Historic and contemporary land-uses, large wildfires, exotic plant invasion, and woodland expansion all represent threats to this multiple-use landscape. Efforts of federal and state agencies and private landowners across the landscape are focused on restoration and maintenance of conditions...

Big sagebrush plant communities are important and widespread in western North America and are crucial for meeting long-term conservation goals for greater sage-grouse and other wildlife of conservation concern. Yet wildfire is increasing in the West, turning biodiverse, shrub-based ecosystems dominated by sagebrush into grasslands containing invasive species such as cheatgrass and less...

Fisheries in the glacial lakes region of the upper Midwest are culturally, economically, and recreationally beneficial. Walleye, for instance, represent an important subsistence food source for some Wisconsin tribal nations and are also popular among recreational anglers. However, predicted ecological changes to these aquatic communities, such as an increase in invasive fish species, a...

The sagebrush rangelands of the Great Basin provide crucial habitat for a diversity of wildlife, including the pronghorn and the greater sage-grouse. These water-limited, highly-managed ecosystems have already been degraded by wildfires, the expansion of invasive grasses, and livestock grazing, and are expected to experience additional stress as climate and land use conditions change...

Sagebrush steppe is one of the most widely distributed ecosystems in North America. Found in eleven western states, this important yet fragile ecosystem is dominated by sagebrush, but also contains a diversity of native shrubs, grasses, and flowering plants. It provides critical habitat for wildlife like pronghorn and threatened species such as the greater sage-grouse, and is grazed by...

Landscape-scale conservation of threatened and endangered species is often challenged by multiple, sometimes conflicting, land uses. In Hawaiʻi, efforts to conserve native forests have come into conflict with objectives to sustain non-native game mammals, such as feral pigs, goats, and deer, for subsistence and sport hunting. Maintaining stable or increasing game populations represents...

The headwaters of the Columbia River Basin in the Northern Rocky Mountains region is widely recognized as a stronghold for native fish, containing some of the last remaining connected cold-water habitats for species such as the threatened bull trout and native westslope cutthroat trout. However, as temperatures rise, non-native invasive fish species could be poised to prosper in the...

There is growing interest in the facilitated movement of plants as a means of conserving or restoring species and habitats, as climate conditions and management goals change. For example, plants might be relocated to support pollinator conservation or the restoration of prairies. Some land managers, in an effort to be proactive in the face of changing environmental conditions, are also...

The Rio Grande cutthroat trout is New Mexico’s state fish; but habitat loss and non-native trout invasions threaten the persistence of this fish throughout the remaining 12% of its historic range. Stakeholders, including state agencies, federal agencies, Tribal nations, Pueblos, and private groups are particularly concerned about the impact that non-native brown trout have on native...

As the origin of three major basins that drain the Columbia, Missouri, and Saskatchewan rivers, Montana is the hydrologic apex for North America. The Northern Rocky Mountain region is home to some of the last remaining interconnected habitats for many native fishes, including the threatened bull trout and native westslope cutthroat trout. The Northern Rockies are also experiencing...

Invasive species have increasingly severe consequences for ecosystems and human communities alike. The ecological impacts of invasive species are often irreversible, and include the loss of native species and the spread of disease. Implications for human communities include damaged water transportation systems, reduced crop yields, reduced forage quality for livestock, and widespread...