Zimmerman Lake, Roosevelt National Forest.
Zimmerman Lake is located within Roosevelt National Forest. This forest is located in the north-central portion of Colorado, and even reaches to the Wyoming state line. Conjoined with the forest is the Pawnee National Grassland. Together, these two entities of land encompass 1.5 million acres. Headquarters for the Roosevelt National Forest are located in Fort Collins, Colorado.
Often, Roosevelt National Forest is paired along with Arapaho National Forest, forming what is referred to as the Arapaho-Roosevelt National Forest. Within this area recreational activities are abundant. Guanella Pass Scenic Byway is a great place to drive and observe colorful aspens, alpine streams, and two 14,000 foot peaks. Along this byway, and many others located within the forest, there exist several hikes to pristine mountain views. Yet another great option is Poudre Canyon road, which offers scenic views of the Poudre River, along with later access to State Forest State Park. Along this road you can find Zimmerman Lake, which is a great place to catch Colorado’s state fish, the Greenback cutthroat trout. All in all, the Arapaho-Roosevelt area provides excellent access to hiking, biking, and fishing not too far from Denver.
- Jacob Lacy
Greenback Cutthroat Trout.
Greenback cutthroat trout are native to the beautiful waters of Colorado. They have reddish coloration in their lower jaw and throat, as do all cutthroats. They are also distinguished by their prominent spots and dark olive colored back. Greenback cutthroat trout currently inhabit a small portion of Colorado. The species is far more isolated than its’ historical locations. In the past, Greenbacks could be found cruising the waters of the South Platte and Arkansas River drainage. Unfortunately, their time spent on their original breeding grounds has come to an end.
There was an assortment of issues that contributed to the rapid loss of the Greenback cutthroat population around 1930. Irrigation and harvest by settlers, invasive species, and mining all presented huge threats to the population of these species. The number of Greenbacks dwindled down to such a dramatic low, that they were believed to have gone extinct. 30 years later, the species was located and classified as endangered. At this point, they can be found above barrier falls in small headwater streams. With time, Greenbacks were revived through a variety of projects, placing them in the Threatened Species category.
Rocky Mountain National Park was the holding ground for Greenback restoration projects. Hatchery fish from remaining populations were used to stock 62 miles of lake and 102 miles of stream. It was thought to be a roaring success until bad news struck. These so called “Greenback” cutthroats were actually Colorado River cutthroat trout.
This new information left Greenback cutthroat trout with only two inhabited bodies of water. Southwest of Colorado Springs is Bear Creek, home to the Greenback cutthroat. The water in which the Greenback’s reside in is a 4 mile stretch above a natural barrier. Many efforts have been made to rejuvenate the existence of this native species. As well, Zimmerman lake, a lake in the South Platte River drainage, has been stocked with an extensive amount of Greenback cutthroat.
Due to the fact that these fish are living in closer quarters than they once were, mating has created issues. Incest amongst the species has led to a large assortment of genetic mutations, including a prominent double chin and cataracts. Hopefully, with research and time, this species will one day return to its historical habitat and lifestyle in full force.
This native species helped inspire and form a community of anglers called The Greenbacks. The Greenbacks are a Colorado based organization that promotes native trout and conservation efforts strongly. The majority of their efforts are focused towards involvement an exposure of the next generation. Go ahead and check out The Greenbacks and their impressive community at http://thegreenbacks.org
If you are interested in learning more about Greenback cutthroat trout, feel free to follow this link http://www.tu.org/stateofthetrout
- Heather Harkavy
Population Health Survey.
With all the information that we have gathered and experienced through various Greenback cutthroat trout projects, it all came full circle during our time at Zimmerman Lake. We met up with Boyd Wright, the Native Aquatic Species Biologist for Colorado, who works with multiple native species in need of protection and management. Zimmerman Lake is home to the majority of Greenback cutthroat in the state and also serves as the main location that Colorado Parks and Wildlife uses to collect egg and sperm to use in breeding more of this species.
Fish sampling is conducted with traps that are set up the night before in two different locations to gather as many fish as possible. First thing in the morning, the research team collects the fish that enter the trap and sort them into temporary holding based on colored markers that are tattooed behind the eyes of the fish. These colored markings designate what year the fish was released and what their genetic make up is. After this initial sorting, the fish are then brought, via bucket, to a temporary station set up on the lakeside. My job at this station was to take the Greenbacks from that bucket and put them into a tank with a sedative in it, which harmlessly calms and sedates the fish. This way they can be weighed, measured, and checked for a PIT tag (which gives each fish a unique ID). During this process any deformities such as double chins, cataracts, or even hooking marks from anglers are announced to the technician recording the data.
The fish sampled were just getting ready to spawn, so the data collected helps to get an idea of the health of the fish in the lake. Boyd told us that they would be coming back early the next week to collect egg and sperm samples when the fish were ready.
Even though none of us caught a Greenback cutthroat while we were there, it was incredible to successfully handle, sample and release about 400 of this threatened species. From our visit at Bear Creek in Colorado Springs, to Zimmerman Lake, it is truly amazing to see all the different groups working together for the greater good of these resilient fish.
- Austin Burroughs