Innovative and collaborative effort designed to save endangered fish in Colorado River

Razorback sucker fish on their way to recovery.

Moab, UT

razorback sucker fish
Razorback Sucker Young fish are measured and tagged to monitor this freshwater species. © Erika Nortemann/The Nature Conservancy

Razorback suckers living in the Colorado River are raising their fins to celebrate. After facing extinction for more than 30 years, the U.S. Fish and Wildlife Service will recommend their status change from Endangered to Threatened.

Why? Because of innovative and collaborative partnership projects, including the Green River fish nursery, which is now being replicated along the main stem of the Colorado River at The Nature Conservancy’s Scott M. Matheson Wetlands Preserve. Construction is underway.

The fish – with a sharp-edge hump behind its head – has the potential to live up to 40 years. However, most razorback suckers don’t live past their first year.

Spawning occurs in the main stem of the Colorado River during the spring when water is running high and fast. Historically, the larvae drift from the spawning area and enter backwaters or wetlands where they are protected and grow into young fish. With fewer of these habitats available, the fish are susceptible to predators, particularly non-native fish, and populations have declined.

State and federal agencies and The Nature Conservancy have developed an innovative solution to increase their life span. They’re building a nursery at the preserve near Moab to provide a safe place with warm, shallow water where the larvae can become adults.

The project will improve the existing wetland by opening a channel from the Colorado River to the property’s central pond. This will allow more water into the preserve during spring runoff.

“We’re excited about this collaborative effort, which is based on successful work by our colleagues on the Green River,” said Zach Ahrens, a native aquatics biologist with the Utah Division of Wildlife Resources. “The Colorado River system has changed a lot in the last century, and wetland habitats like the Matheson Preserve aren’t as wet as they have been in the past. By flooding it more often and for longer periods, we expect to provide crucial habitat that these fish have lost.”

Engineers will also design a control structure that will allow water into the preserve wetland during spring runoff, maintain that water throughout the summer and allow drainage in the fall when the larvae have matured.

“This unique structure will be the key to our success,” said Ryan Jolley, PE Engineering Project Manager. “It will have a specially designed concrete channel with a control gate and screen system that will only allow the larval fish to pass while keeping non-native predatory fish from entering. The structure will also have a fish capture area where the young fish can be measured and tagged before being released back to the Colorado River.

The Preserve’s central pond will be drained prior to the introduction of larvae to remove non-native fish that entered the wetland as larvae during the previous year. Large machinery will also deepen the pond to increase habitat size and optimize water quality.

“Research indicates the Scott M. Matheson Wetland Preserve is the only suitable wetland nursery habitat along 65 miles of the Colorado River. We’re thrilled to be part of this cutting-edge effort to help the razorback suckers become self-sustainable once again,” said Linda Whitham, The Nature Conservancy’s Central Canyonlands Program Director.

In addition to creating a critical habitat for the fish, this project will bring more water to the Preserve’s unique wetland ecology, which supports native vegetation, provides flood protection for Moab and helps deter wildfires.

The Nature Conservancy is a global conservation organization dedicated to conserving the lands and waters on which all life depends. Guided by science, we create innovative, on-the-ground solutions to our world's toughest challenges so that nature and people can thrive together. We are tackling climate change, conserving lands, waters and oceans at an unprecedented scale, providing food and water sustainably and helping make cities more sustainable. Working in 79 countries and territories, we use a collaborative approach that engages local communities, governments, the private sector, and other partners. To learn more, visit or follow @nature_press on Twitter.