Threatened and Endangered Species

Partners in Science is a collaborative effort between Grand Canyon Monitoring and Research Center, Grand Canyon Youth, and the National Park Service to provide opportunities for youth to engage in scientific field research in Grand Canyon. This partnership connects youth from diverse backgrounds with the Nation’s natural and cultural resources on 2-3 river-based expeditions on the Colorado River...

Rainbow trout are a desirable sport fish that have been introduced in many locations around the world, including the Colorado River. Although introductions of rainbow trout and other nonnative fishes provide recreational fishing opportunities, they can also pose threats to native fish populations. The Glen Canyon Dam Adaptive Management Program has tasked scientists and managers with identifying...

USGS Southwest Biological Science Center's Grand Canyon Monitoring and Research Center prepared a cooperator publication and a presentation that report on modeling results to evaluate potential effects of reservoir management on various resources in Lake Powell and Grand Canyon.

Grand Canyon National Park is a hotspot for bat diversity. Twenty-two bat species have been documented in the Park, more than any other national park unit.

The saguaro cactus ( Carnegiea gigantea ) is a keystone species that grows only in the Sonoran Desert of northern Mexico and the southwestern United States. The USGS’ Southwest Biological Science Center is working to better understand the species’ biological features, its role as a keystone species that supports greater than 100 other plant and animal species, and its responses to climate change...

Did you know that moths can be pollinators? Even more amazing is that Joshua trees, the scraggly icons of the Mojave Desert, require a single moth species to ensure fertile seed production. The association between the Joshua tree and its pollinating moth is a rare example of an obligate mutualism, which means that the species are entirely dependent upon each other. Joshua trees depend on the moth...

Threatened humpback chub are a native fish found only in the Colorado River Basin. Once found in warm-water canyons in the Basin, the largest population now persists in the Colorado River in Grand Canyon National Park, downstream of Glen Canyon Dam and Lake Powell, the reservoir upstream, created by the dam.

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...

The United States is developing renewable energy resources, especially solar, at a rapid rate. Although renewable energy development is widely perceived by the public as “green technology,” construction, operation, maintenance, and eventual decommissioning of facilities all have known and potential negative impacts to natural resources, including plant communities and wildlife. This is especially...

Glen Canyon Dam has altered ecological processes of the Colorado River in Grand Canyon. Before the dam was built, the Colorado River experienced seasonable variable flow rates, including springtime flooding events. These spring floods scoured the river bottom and enhanced natural processes that sustained the Colorado River ecosystem. Since the dam’s construction in 1963, springtime floods have...

The desert Southwest is experiencing rapid development of utility-scale solar and wind energy facilities. Although clean renewable energy has environmental benefits, it can also have negative impacts on wildlife and their habitats. Understanding those impacts and effectively mitigating them is a major goal of industry and resource managers. One species of particular concern is Agassiz’s desert...

Introductions of bio-control beetles (genus Diorhabda) are causing defoliation and dieback of exotic Tamarix spp. in riparian zones across the western U.S., yet the factors that determine the plant communities that follow Tamarix decline are poorly understood. In particular, Tamarix-dominated soils are often higher in nutrients, organic matter, and salts than nearby soils, and these soil...