Colorado Parks and Wildlife recently announced ongoing efforts to save a unique species of cutthroat trout rescued from Hayden Creek near Canyon City, Colorado. CPW biologists discovered the trout in 1996, but the discovery has not been promoted.
A year ago the Hayden Creek area experienced a wildfire that threatened the entire population of cutthroats. A team of biologists and volunteers went in ahead of approaching fire lines and netted 194 fish. 158 of the fish were placed in a captive breeding program, and the remaining 36 were released in a nearby drainage to breed naturally. Soon after the fire passed through the area, seasonal monsoon rains washed significant amounts of mud and ash into the creek. The debris smothered remaining insect life and spawning beds. Since the fire, biologists have been unable to find a single trout in Hayden Creek.
As of the date of the press announcement (6/23/2017), captive breeding efforts continue, and plans are underway to resurvey Hayden Creek for wild survivors this fall.
So the question that remains is, are these cutthroat the legendary "yellowfin" cutthroats of twin lakes, Colorado? In 1889 professor David Star Jordan visited Twin Lakes and collected specimens of a large species of cutthroat (up to 10 pounds) with bright golden yellow fins. The two preserved specimens are stored at the Museum of Natural History at the Smithsonian in Washington DC. The subspecies was eventually named Oncorhynchus clarkii macdonaldi . Yellowfins survived in Twin Lakes alongside greenback cutthroats as distinct, non-breeding populations until about 1903. At this point non-native rainbows were introduced to the lake. The greenbacks interbred with the rainbows to produce cutbows, and the yellowfins disappeared completely. Though there have been periodic reports of living yellowfins for the past 100 years, none of these reports have ever been verified.
While the CPW press release does not specifically call this Hayden Creek population "Yellowfins", it does mention David Star Jordan, and says that the genetics of the Hayden Creek cutthroats match those of the Smithsonian specimens. Do they display the size and distinctive yellow fins? Again the press release is silent on these points. It could be possible however that the size and distinctive coloration only manifest when the fish live in suitable environments, i.e. Twin Lakes and not a small creek.
It's exciting to think that the yellowfin may not be gone. After all, it wouldn't be the first time a species of cutthroat came back from the dead.