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Photo credit: Colorado Department of Natural Resources

Rio Grande sucker (Catostomus plebeius) | ESA status: petitioned for listing

Rio Grande sucker

This small fish was once common in the Rio Grande. It is under threat from water withdrawal, dams, and diversion.

Rio Grande sucker habitat

The Rio Grande sucker is found in the Rio Grande and its tributaries in southern Colorado, New Mexico, and several states in Mexico. The Rio Grande sucker has suffered significant range contraction and population decline since the late 1800s.

What are the threats to the Rio Grande sucker?

Runoff and sediment loads from logging, large-scale agricultural practices, and livestock grazing, among other factors, have decreased habitat quantity and quality for the sucker. Diversion of water for agriculture reduces stream flows and destroys habitat. Dams and diversions are fragmenting populations. The sucker is also subjected to competition from introduced fish species, in particular the white sucker. Climate change is projected to exacerbate current threats as well as further tax the already-strained river. The state of Colorado recognized the precarious position of the Rio Grande sucker by listing it as “endangered” in 1993 and published a recovery plan for the species in 1994. Unfortunately, the state listing did not stem the species’ decline.

What WildEarth Guardians is doing to protect the Rio Grande sucker

In 2014, Guardians submitted a scientific petition requesting listing for the chub under the Endangered Species Act. The petition received a positive 90-day finding, the first step in the listing process, in March of 2016.