The Texas Trout

Today the only member of the family Salmonidae (trout, salmon and their relatives) that occurs in Texas is the non-native Rainbow Trout Oncorhynchus mykiss. That species is widely stocked around the state and there is one permanent population in McKittrick Creek, Guadalupe Mountains National Park, where it was introduced in the early 1900s. However, historical records indicate Texas probably had its own native trout, the Rio Grande Cutthroat Trout Oncorhynchus clarkii virginalis (Garrett & Matlock 1991 Rio Grande Cutthroat Trout in Texas)

In 1878, the wildlife conservation and sporting magazine, Forest and Stream, reported that a surgeon stationed at Fort Davis, Texas during the Civil War took "Salmo fontinalis" from nearby Limpia Creek. Another surgeon who traveled in western Texas and New Mexico during the Civil War period wrote in Forest and Stream (also in 1878) about catching "S. fontinalis" in Texas in the Devils River at Fort Hudson, as well as in Limpia Creek. He also reported taking this species from the "Rio Benito" at Fort Stanton, New Mexico, and from other mountain streams in New Mexico. The Rio Bonito is a tributary of the Pecos River and is known to have contained Rio Grande Cutthroat Trout at that time (Behnke, R.J. 1979. Monograph of the native trouts of the genus Salmo of western North America. U.S.D.A. Forest Service, Rocky Mountain Region, Lakewood, Colorado); therefore, his trout identification skills were likely sufficient to recognize the species in question. An editor's note following the article stated that the presence of trout in Texas had been firmly established by "ample testimony." A drawing of the fish was accompanied by the description: "yellowish brown above, spotted with black; a red band on each side of the chin." Although the drawing is rather generic, the description is correct for Cutthroat Trout, and of particular significance is the reference to a red band, a diagnostic character for Cutthroat Trout.

In 1894, Evermann and Kendall (The fishes of Texas and the Rio Grande basin, considered chiefly with reference to their geographic distribution. Bulletin of the U.S. Fish Commission, Article 3:57-126) listed "Salmo mykiss spilurus" as in Texas at "Limpia, Devil River, San Felipe Springs, and headwaters of the Canadian River, Texas, and Rio Bonito, New Mexico."

By the mid-20^th century, trout were still being discussed as native or possibly native to Texas. Baughman (1950. Random notes on Texas fishes. Texas Journal of Science 2:117-138.) listed S. spilurus as having a range that included Texas. Knapp (1953. Fishes found in the freshwaters of Texas. Ragland Studio and Litho Printing Co., Georgia) noted the only possible locality for native trout in Texas was in the Davis Mountains (Limpia Creek) and that "oldtimers" had stated that trout were present in that location, but the reports were never verified.

Another native Texas fish, the Rio Grande Chub Gila pandora (Hendrickson 2019 Rio Grande Chub), provides additional clues about the validity of a native Texas trout. Its only occurrence in Texas is as a small, isolated population in the Davis Mountains, but otherwise its current range throughout the upper Rio Grande and Pecos River drainages in New Mexico and Colorado is very similar to the current range of Rio Grande Cutthroat Trout.

Many species extended their ranges southward during the Wisconsin glacial period (75,000 - 11,000 years ago). For aquatic organisms in particular, what is now the Chihuahuan Desert was a route for dispersal during this time. Both Rio Grande Chub and Rio Grande Cutthroat Trout likely expanded their ranges and had a more widespread and continuous distribution during this wetter and cooler period, but as conditions became drier and warmer, ranges diminished and relict populations were left behind in small patches of suitable habitat. Today Rio Grande Chub persists (barely) in Texas, but Rio Grande Cutthroat Trout didn’t quite make it into modern times.

Catalogued, preserved specimens of Rio Grande Cutthroat Trout from locations in Texas would have provided conclusive evidence, but it appears there are none. Although less than ideal, the historical accounts do present a likely and compelling scenario for the natural occurrence of this species in the state (http://www.fishesoftexas.org/specimen/FoTX%20unvouchered1).

Unfortunately, the Rio Grande Cutthroat Trout is now rare throughout its native range (Western Native Trout Status Report). Maybe someday spring-fed Texas streams could once again support our native trout and provide it safe haven for the future.

Gary Garrett is a Research Associate in the Ichthyology Collection