Fishes

Riparian plant communities, associated with rivers and streams, are ecologically and culturally important areas in the southwestern U.S. Despite covering less than 2% of the land area in the southwest, the resources provided by these communities make them valuable to wildlife, the public, scientists, and resource managers.

Invasive species can harm ecosystems, increase wildfires, damage forests, and outcompete native species. The US Geological Survey's Southwest Biological Science Center conducts research that provides our federal and state partners, cooperators and land managers with the tools, data and strategies to enhance biosecurity management. Scroll through the information below to read about different SBSC...

A study conducted by the USGS provides new insights into the migration patterns of three native fish species in the Colorado River: humpback chub, flannelmouth sucker, and bluehead sucker. This research highlights the importance of understanding native fish population dynamics within the Colorado River ecosystem in Grand Canyon, AZ.

The Grand Canyon Monitoring and Research Center, a branch of the Southwest Biological Science Center, conducts scientific assessments of the Colorado River in Grand Canyon, focused primarily on Lake Powell and the river ecosystem downstream of Glen Canyon Dam. On this page, we'd like to share related interactive tools and projects by other USGS Centers that cover science across the upper and lower...

In the Upper Colorado River Basin, smallmouth bass ( Micropterus dolomieu) are considered the greatest threat to native fishes and have been linked to declines in federally protected humpback chub ( Gila cypha), including one population that was rapidly extirpated in the past. Long-term management efforts have been underway to remove smallmouth bass from rivers in the Upper Basin, but smallmouth...

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.

The Southwest Biological Science Center (SBSC) conducts and provides scientific information as part of our mission and Federal Trust Responsibility to strengthen relationships and build partnerships with sovereign tribal nations. Here, we highlight a few examples of projects with tribal partners.

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 provided scientific expertise to evaluate potential effects of reservoir management on various resources in Lake Powell and Grand Canyon. This information, published in a cooperator report, was requested and used by the Bureau of Reclamation for decision-making on water flows from Glen Canyon Dam.

Renewable energy development is expanding in southwestern deserts, including in Arizona. Energy developers look to resource management agencies to provide siting guidance on public lands where there might be conflicts with wildlife. Often, agency guidance considers species of conservation concern and economic importance, but information on comprehensive vertebrate biodiversity has been hard 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...

Algae, phytoplankton, and rooted macrophytes represent the base of many aquatic food webs and are known as primary producers. Through photosynthesis, these organisms convert sunlight energy into chemical energy (i.e., carbon) that in turn fuels the growth of animals such as macroinvertebrates and fish. This project uses high frequency measurements of dissolved oxygen, which is a by-product of...