Steamboat Springs After years of exploring small streams in remote corners of Northwest Colorado working to save the Yampa River Basin’s only native trout, U.S. Forest Service fish biologist Rick Henderson never expected to find a pure strain of Colorado River cutthroats on the slopes of Steamboat Ski Area.
“Who’d have thought I’d have them right out my door?” Henderson asked figuratively.
But there they are in Burgess Creek, not far from the bottom of the chairlift of the same name. The cutthroats are named after the twin slashes of crimson markings beneath their jaws.
And now, with the help of cohorts Billy Atkinson, of Colorado Parks and Wildlife, and Brian Hodge with Trout Unlimited, Henderson is embarking on a project to boost the population of cutthroats by segregating them from the non-native brook trout in Burgess Creek. The brookies have a competitive advantage against the local fish.
Tests have confirmed, Henderson said, that the fish discovered in a one-mile stretch of Burgess Creek in 2014 are 100 percent genetically pure. That makes them one of only 13 known pure Colorado River cutthroat trout populations in the Yampa River Basin.
Colorado River cutthroat trout represent a sub-species of cutthroats that are not a federally-listed threatened or endangered species. However, the Forest Service considers the fish a “sensitive” species, and Colorado Parks and Wildlife regards them as a species of special concern.
Within the past 150 years, the distribution of the native cutthroats has declined significantly until they currently occupy only 14 percent of their historic streams. Part of that is due to human activity and part to non-native fish.
Brook trout spawn in the fall, and lay their eggs during winter before hatching in early spring, Henderson said. By the time cutthroats spawn in the late spring and hatch in mid-summer, the brook trout fingerlings are already gaining bulk and strength. That enables them to muscle cutthroat fingerlings out of prime winter habitat, reducing the chances for the natives to survive to see a second summer.
The upper terminus of the Colorado River cutthroat troat's one-mile stretch of Burgess Creek is near the bottom of the Four Points chairlift. The lower end of the cutthroat’s range is a 5-foot tall waterfall, which effectively blocks brook trout in the lower reaches of the stream from moving upstream (brook trout can’t leap over waterfalls similar to salmon and cutthroats).
Henderson said the Colorado River cutthroats are well protected by thick stream-side vegetation, and as a result, he’s not concerned that drawing attention to them will result in over-fishing.
“It’s a very healthy population,” he said. “The fish grow up to 10 inches and they’re all fat.”
Still, increasing the length of stream they occupy would increase the long-term viability of the population. Toward that end, Henderson and Atkinson intend in 2017 to replace two culverts in that short stretch of Burgess Creek to improve aquatic passage for the trout and improve hydrology.
Pitching in on the project are the local Trout Unlimited chapter, the Yampa Valley Fly Fishers and the Yampa River Stream Improvement Trust. Henderson said Steamboat Ski and Resort Corp. has offered to provide construction labor and equipment for the culvert project.
The second stage of the project, which could stretch across five years, involves electrofishing to capture and relocate a majority of the brook trout in lower stretches of the creek, including 0.7 miles of stream within the National Forest and 1.3 miles on private land.
At the downstream edge of the electrofishing effort, a manmade waterfall adjacent to the Torian Plum condominiums would prevent brook trout from returning to the upper stream.
“There are 14 landowners between the waterfall and the forest boundary,” Henderson said. “So far I have 12 permissions, and I’m working on the other two. It’s been nothing but positive.”
To reach Tom Ross, call 970-871-4205, email tross@SteamboatToday.com or follow him on Twitter @ThomasSRoss1