The Guadalupe bass is a rare species of fish endemic to the U.S. state of Texas, where it also is the official state fish. It is restricted to creeks and rivers, and is listed as near threatened. Today, most fly fishermen and anglers practice catch-and-release techniques to improve fish populations. The Guadalupe bass is often difficult to distinguish from the smallmouth bass or spotted bass, and the fish is known to hybridize.

The Guadalupe River runs from Kerr County, Texas, to San Antonio Bay on the Gulf of Mexico, with an average temperature of 17.75 degrees Celsius. It is a popular destination for rafting, fly fishing, and canoeing. Larger cities along it include Kerrville, New Braunfels, Seguin, Gonzales, Cuero, and Victoria. It has several dams along its length, the most notable of which, Canyon Dam, forms Canyon Lake northwest of New Braunfels.