Aquatic Food Web

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 Grand Canyon Monitoring and Research Center maintains an enterprise GIS platform built upon ESRI ArcGIS Server and Portal applications. This enterprise system allows for spatial data, maps and analytical tools to be served through online applications. The Geospatial Science and Technology project provides access to this content through different avenues. Online maps can be accessed through...

The Grand Canyon Monitoring and Research Center offers a collection of data resources and online tools -- including web maps, applications, and other content -- that convey scientific information related to on-going monitoring of the Colorado River. Some applications are a culmination of long-term monitoring work, while others are developed around more a specific set of information usually derived...

Aquatic invertebrates are critical food for fish and other species that inhabit large rivers. In the Colorado River Basin, invertebrates that get transported down the river (“in the drift”) are particularly important to rainbow trout and other species of interest to recreational users. This research seeks to compare rivers downstream of large dams throughout the Colorado River Basin in order to...

All aquatic invertebrates drift downstream at some point in their life cycle. Invertebrates may drift to find more preferable habitats, to leave the water during their transition from aquatic larvae to terrestrial adults, or accidentally such as when swept off the riverbed by a flood. Regardless, when they enter the drift, invertebrates become particularly susceptible to predation by several...

Aquatic insects live in the water as larvae most of their lives, then emerge onto land for a brief period as winged adults. Sampling these emerged adults on land is therefore a useful tool for understanding the condition of the aquatic insect population that is in the water, particularly in large rivers where sampling the larvae on the river bed is impractical. Our group uses a variety of methods...