In 1937, Colorado's native greenback cutthroat trout (Oncorhynchus clarki stomias) was believed to be extinct. Many attribute the greenback's decline to pollution, habitat loss, and predation as a result of intensifying front-range settlement during the late-1800s and the turn of the century. Importantly, in 1873, an old homesteader named Joseph C. Jones set out to strike it rich by developing a hotel and restaurant along Bear Creek (a tributary of the Arkansas River) in hopes of alluring tired travelers hiking a newly completed trail to and from the summit of Pike's Peak. Unknowingly, Jones would become an accidental conservationist.
Researchers now believe that Jones may have stocked Bear Creek and some nearby ponds with a genetically pure strain of greenback cutthroat trout. From where exactly he obtained the stocks remains unclear. But it's believed that by stocking the creek, Jones simply intended to improve the recreational fishing near the hotel. Little did he know, his investment would eventually save the last known population of pure greenback cutthroat trout. Due to physical barriers within Bear Creek downstream of the Jones homestead, the stocked greenbacks were protected from other species of fish in the lower reaches of Bear Creek, allowing the greenbacks to avoid potential predators and hybridization with non-native trout over the ensuing 130 years.
By the 1970s, the greenbacks were listed under the Endangered Species Act: first as endangered, then down-listed as threatened a few years later. Since then, an aggressive federal and state recovery effort followed to protect and restore various "greenback" populations across what was then believed to be their historical range on the eastern slope of the continental divide. However, decades later in 2012, cutting edge aquatic genetic research at the University of Colorado revealed earth-shattering results; we were focused on the wrong fish. As it turns out, the greenbacks identified for protection on the eastern slope were, in fact Colorado river cutthroat that were likely propagated and stocked across the continental divide. The 2012 study (Metcalf et al. 2012) found that between 1885 and 1953, up to 750 million trout (including cutthroat trout) were raised and transplanted from the western slope throughout the state, including to the eastern slope. Old notions that greenbacks and Colorado River cutthroat (which are difficult to distinguish based on physical traits alone) can be identified reliably by geographic range (east vs. west slope, respectively) have been repudiated. The 2012 study also concluded that the Bear Creek greenbacks were the last living vestige of the true greenback trout in Colorado.
Local Aquatic Biologist with Colorado Parks and Wildlife (CPW), Kendall Bakich recently discussed these issues and their relevance to the Roaring Fork Valley in an article published by Roaring Fork Lifestyle magazine. According to Kendall, "In the Roaring Fork Valley we have two genetically pure green-lineage populations. . . . They're vulnerable." The two populations reside in Hunter Creek, a tributary of the Roaring Fork, near Aspen and in Cunningham Creek, a tributary of the Fryingpan River. The primary threats facing these fish are potential hybridization and invasion by non-native species, such as brook trout and others. Through Kendall's team, CPW conservation and reclamation efforts are beginning to take shape in these two local streams.
Will we learn the true origin of the "green-lineage" cutthroat here in our valley? Did the Roaring Fork Valley have its own accidental conservationist, like Joseph C. Jones? Or are these unique populations of native fish? Time will eventually tell. But for now, please stay informed on this important and unfolding effort. The plan will likely take many years of significant work to accomplish. But hopefully the effort will result with yet another important chapter of the storied history of the greenback cutthroat trout.
For more background on the Bear Creek greenback recovery program, take a look this video produced by CPW: