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Colton Gully

Protecting and Restoring the Greenbacks

Originally published in High Country Angler, Winter 2016 edition (, reprinted by permission from Colorado Trout Unlimited.

Our roots as Coloradans date back to the pioneers, their fortitude, determination and success depended on their ability to endure and overcome hardship. When they settled the Front Range and expanded into the mountains in search of riches they were sure of the task at hand, collected as individuals seeking the same end, to settle a rugged mountain range. It was this shared goal that brought them together in the face of daunting odds. Like the pioneers modern day Coloradans are embarking on an uphill journey to save our state fish, Greenback Cutthroat Trout, from extinction.

Greenback swimming in sediment loaded bear creek.

Greenback swimming in sediment loaded bear creek.

A group of like minded organizations have been working to reintroduce these fish into their native range in the South Platte River Drainage. As separate entities devoted to the same goal since 2012 when Jessica Metcalf of CU Boulder released her genetic study verifying the last remaining population of greenbacks in the world living in a Bear Creek on the outskirts of Colorado Springs, these organizations have made great headway towards Greenback recovery. Metcalf’s study provided the scientific evidence to prove the uniqueness of our state fish while uniting state and private entities in the quest for greenback recovery. Without a collective forum for the recovery effort, relative and in the now information has been hard for the public to come across. At Colorado Trout Unlimited (CTU) we are working to create a public interface that allows organizations working to further greenback recovery to effectively update the public. To do this CTU has created web pages on their site where all CTU chapters can post the work they are doing to further the greenbacks find at under the Greenback Recovery Efforts tab. Through this interface we hope to sound a collective cry for our state fish that evokes a call to keep Colorado native.

Through DNA analyses, Metcalf enabled a new approach to breeding trout in captivity. With only 750 wild greenbacks left in the wild, a genetic bottleneck threatens the wellbeing of the entire population. Without a clear understanding of how genetics effect the greenbacks it would be easy to breed the current population into a downward spiral. Ed Stege, head biologist at the Leadville National Fish Hatchery, will apply Metcalf’s genotyping science to selective breeding of greenbacks. Genotypes of greenbacks in captivity will be analyzed and cross referenced by the genetics team at CU Boulder; this genetic matrixing will provide fisheries biologists with a spread sheet of relatedness so they can breed the most distinct fish making ensuring the resulting offspring are fit as possible. Stege will use this method as a guiding principle in an ongoing effort to breed a tiny population of greenbacks away from a genetic bottleneck. The genetic science surrounding the greenbacks is groundbreaking. Colorado has blazed a path of progress in hatchery science but the science does not stop in captivity; selective breeding is key to the survival of greenbacks in the wild. Greenbacks will be reintroduced into a varied range of ecosystems up and down the Front Range, when natural reproduction occurs it will be much more productive if genomes of the fish are distinct. As research continues, populations of greenbacks stocked in streams will be monitored for several years to track breeding success and survival rates. Work like this is already being done in Zimmerman Lake but with minimal spawning habitat it is hard to know what natural reproduction will bring.

Bear Creek is home to the 750 remaining wild native greenback in Colorado. The stream is not in the greenbacks native range nor is it a healthy ecosystem. Sediment loading from spring runoff, summer rains and the proximity of the stream bead to a road, High Drive, and other trails causes a multitude of problems from depleted insect and plant life to a scarcity of holding water. This summer The US Forest Service received and reviewed a NEPA Process (environmental assessment) on the Bear Creek ecosystem. The recovery plan outlined in the report will significantly improve the aquatic and riparian health of Bear Creek. Sediment runoff from High Drive will be minimized by repairing culverts, creating floodplains, the installation of local sediment traps, increased capacity of road side ditches and decreased road width where possible. Upland areas effected by erosion will be replanted with native plants to decrease sediment loading and to help with flood control. Improvements in the riparian habitat will help to ensure the work being done in the stream will be lasting. To create more holding water, new and existing logs and rocks will be strategically placed to make the most plunge pool habitat. Eroding banks will be replanted with native plants to decrease sediment runoff and provide an ecosystem for insects. The existing fish barrier that does not allow the passage of nonnative fish into the stream will also be improved and fishing will continue to be banned. Although the NEPA document outlined the restoration and intended goals for the ecosystem it is not a funding document or timeline. Colorado Trout Unlimited (CTU) and The Pikes Peak Chapter, a local CTU chapter, have both made restoring Bear Creek a priority. Through crowd funding, grant work and political advocacy at both the state and local levels they are working towards securing funding and a timetable for the restoration of Bear Creek. Although the NEPA document does not outline any funding for the project some initial funds have been allocated by El Paso County. Colorado Springs gave Jones Park to El Paso County in early 2014 under the understanding that the county would allocate funds for the restoration of Jones Park. Working to spearhead the restoration is The Bear Creek Roundtable. A local group out of Colorado Springs made up of members from Colorado Parks and Wildlife, The US Forest Service, The Pikes Peak Chapter of CTU, Medicine Wheel Trail Advocates, and others who have a vested interest in Bear Creek and the trails system. They will be playing an integral role when it comes time to negotiate the specifics of the project like start dates, motorized vehicle use, advantage of improvements, plants to be installed and satisfaction of completion.

The remaining greenback in Bear Creek are vulnerable, their susceptibility to whirling disease makes biologists cringe. The disease is in lower Bear Creek already and present in many drainages near Bear like Cheyenne Creek. Whirling diseases is easily transferred by people, fish and vehicles of all kinds making it extremely hard to contain. If whirling disease was to spread up stream into Bear Creek the last wild population of greenbacks would be lost. To prevent this NEPA proposed to ban all human and animal contact with bear creek. The ban could result in physical barriers, fences, being erected and would mandate that before any in stream work is done that all necessary precautions are takin to rid machinery, people and gear of whirling disease. As our state becomes more populated it becomes harder and harder to prevent the spread of invasive disease. It is our duty as anglers and outdoorsman to do all we can to prevent the widespread takeover of these dangers.

Zimmerman Lake taken from the inflow stream.

Zimmerman Lake taken from the inflow stream.

The Leadville National Fish Hatchery USF&WS and the Mt. Shavano Fish Hatchery CPW have been breeding greenbacks for reintroduction since 2010. Their efforts have resulted in the stocking of Zimmerman Lake to the northwest of Ft. Collins. Greenbacks in Zimmerman are the tip of the iceberg as far as reintroduction goes, they are the first hatchery fish placed in the wild and they have shown significantly better growth rates than in the hatcheries. Through natural selection the Zimmerman Greenbacks will be whittled down to only the fittest. These fit fish will provide robust brood stock for reintroduction efforts throughout the South Platte drainage.

Zimmerman Lake Greenback

Zimmerman Lake Greenback

The South Platte Drainage is huge, from the headwaters in the South Platte valley it winds south then north until it meets up with the North Platte in Nebraska becoming the Platte. Some notable tributaries along the Front Range are The Cache Le Poudre, Clear Creek, and Cherry Creek; these tributaries are already well established fisheries and ecosystems so trying to reintroduce Greenbacks into one of these larger bodies would cause more harm than help. To avoid this, Greenbacks will be stocked in smaller creeks that flow into larger tributaries of the Platte. Two tributaries of Clear Creek are currently being prepared for Greenbacks, Dry and Herman Gulch, will have Greenbacks in the near future. Fish barriers have been built in Dry and Herman Gulch with the help of a crowd funding campaign coined 1of750 done by an organization called The Greenbacks and with federal funds. The existing fish in Herman Gulch will be fished out by the West Denver Chapter of CTU and Colorado Parks and Wildlife, the taken fish will be restocked in Clear Creek and then Greenbacks will be stocked in Herman Gulch. This project is set to take place at the end of the 2015 summer so Greenbacks will be in Herman Gulch by spring of 2016. Similar efforts are taking place to prepare George and Cornelius Creeks to the North West of Fort Collins for the reintroduction of greenbacks.

George Creek

George Creek

Fish barriers are being erected and water testing is being done to ensure Whirling Disease is not present. Greenbacks have a huge native range, they have the potential to be reintroduced all over the Front Range in many high mountain streams but some of our beloved water will not be able to be stocked because of disease.

Whirling Disease has plagued streams across the Front Range since the 1980’s. Its effects on rainbow trout ultimately cause death and can wipe out entire populations. Like rainbows, cutthroat are also susceptible to Whirling Disease, this plays a large role when deciding where greenbacks are to be reintroduced. For example, George and Cornelius Creeks are both whirling disease positive in the lower reaches of the creeks but whirling disease negative in the upper reaches. How? You might ask. It is hard to say what exactly brought the disease into the creeks but we can make the assumption that whatever did only fished the lower reaches. Humans are one of the best vehicles for spreading whirling disease. We love to enjoy our open spaces and rivers but often times we forget that we are also a part of the ecosystem. Whirling disease can be transported on waders, boots, boats, live wells and fish. It is our job to be educated about the waters we are walking. Make sure before going out on the water to read up on the health of the streams you will be walking. Also, be sure your waders and boots have been disinfected. This can be done by submerging gear in a large tub with six ounces of quaternary based ammonia products per gallon of water, being sure to scrub away any debris. Or soak all gear in 140 degree Fahrenheit water for ten minutes. Or Dry all gear for a minimum of ten days. Following one of these steps is important preparation before heading out on the water. Now ready to embark on a great day of fishing be sure to fish from the headwaters down as to not contaminate clean water. Whirling disease is difficult to eradicate from a stream once it has been infected. As the organism that spreads whirling disease can only continue to live if fish present, the only way to remove the disease is to remove all the fish and give the parasite adequate time to die without a host. Eradicating whirling disease is out of the question in larger ecosystems, but there are many ways to reduce the impact of the disease. Increased sediment loading provides more habitat for the worms that spread whirling disease to grow and mature. Increased catch and release may also weaken a fish, making it more susceptible to the disease. So, ranching techniques like grazing cattle away from stream beds and not over grazing, along with anglers using barbless hooks and the correct gear to effectively release fish in a timely manner are things we can do to prevent the spread of aquatic hitch hikers. To prevent the spread of whirling disease is to protect our states wild places.

Greenbacks embody the spirit of our state. Their ability to endure holds true to the pioneer way, it gives us hope that someday they will once again thrive in their home range. It will not happen overnight and it will not happen with the stroke of any one pen. It will take a collective group of passionate people surrounded by thousands supporters of all walks of life rallying for the Greenbacks to ensure the progress of this effort. We are privileged to live in one of the most unique states in the country, it is our duty to safeguard the individual species that inhabit it. By reestablishing native Cutthroats in Colorado we are simply doing our duty.

Colton Gully has been working as an intern for Colorado Trout Unlimited since June of 2015. He would like to thank his mentors Bob Garrett and Allyn Kratz for their unwavering support and incredible wisdom. Also he would like to thank Stephanie Scott for her guidance into the world of nonprofits. Funding for this internship came from a GOMO grant secured by CMCTU.

Read about Colton’s internship at

Note: Some photographs were added by Bob Garrett, and were not included in the original publication

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