An initiative of the Center for Environmental Journalism at the University of Colorado Boulder

The westward spread of zebra and quagga mussels shows how tiny invaders can cause...

Fingernail-sized mollusks are spreading through U.S. rivers, lakes and bays, clogging water supply pipes and altering food webs.
The confluence of the Colorado and Little Colorado rivers in the Grand Canyon, shown here in a September 2020 aerial photo from Ecoflight, represents an area where the humpback chub has rebounded in the last decade. That progress is now threatened by declining water levels in Lake Powell, which could lead to non-native smallmouth bass becoming established in the canyon. CREDIT: JANE PARGITER/ECOFLIGHT

Declining levels at Lake Powell increase risk to humpback chub downstream

Low levels and warming waters threaten to increase invasive species in the Colorado River.
Colorado River photo

Traveler Special Report: Grand Canyon’s Struggling River

Glen Canyon Dam, climate change and invasive plant species are threatening the Colorado River.

Colorado River Econ 101

By Kurt Repanshek, National Parks Traveler From the high country in Rocky Mountain National Park a muddy flush of water rushes downstream, through western Colorado. It turns left, going south...

Climate change reducing Colorado River runoff

By Kurt Repanshek, National Parks Traveler By mid-century, annual runoff into the Colorado River could be reduced by nearly a third as declining snowpack leads to greater evaporation of snowmelt,...

Not enough water and too many invasives at Glen Canyon National Recreation Area

Years of drought, upstream diversions and impoundments, and an overly optimistic forecast of Colorado River flows, have sapped the river once literally called Grand.