E in the Colorado River Basin and are a significant predatory threat to four U.S. federally listed species: the Colorado pikeminnow (Ptychocheilus lucius), humpback chub (Gila cypha), razorback sucker (Xyrauchen texanus), along with the bonytail (Gila elegans) [46,47]. Johnson et al.  estimated that northern pike consumed extra fish on a per-capita basis than any other fish species within the Yampa River. Control efforts for northern pike are ongoing inside the Yampa River, which would advantage from far more information and facts regarding sources of recruitment [47,49]. The Yampa River is located in northwest Colorado and flows mostly towards the west from its headwaters inside the Flat Tops Wilderness for the Green River close to the Colorado/Utah border (Figure 1a). Geologic composition underlying the Yampa River is diverse (Figure 1b), and this may well be reflected in water chemistry which ultimately affects the chemical composition of fish otoliths . It truly is largely free flowing, with extreme modifications in flow getting driven by snowmelt . Flows commonly commence escalating in April, with maximum flows in May and June, and after that decreasing flows beginning in July. Northern pike have been stocked in Elkhead Reservoir (that is 98 rkm downstream of Lake Bay K 8644 Epigenetic Reader Domain Catamount within the Yampa River Basin) in 1977 and likely escaped in to the Yampa River in the reservoir inside the late 1970s . Subsequently,Fishes 2021, six, x FOR PEER REVIEW3 ofFishes 2021, six,maximum flows in May well and June, and after that decreasing flows beginning in July. Northern three of 14 pike have been stocked in Elkhead Reservoir (which is 98 rkm downstream of Lake Catamount inside the Yampa River Basin) in 1977 and likely escaped in to the Yampa River from the reservoir within the late 1970s . Subsequently, they spread throughout the Yampa River as there spread all through spot immediately after the dam therebuilt. no barrier in place immediately after the dam they was no barrier in the Yampa River as was was On the other hand, an outlet screen and spillway net have since outletadded to prevent escapementsince been added to prevent was built. Even so, an been screen and spillway net have . Two reservoirs inside the upper Yampa River have established populations of northern pike: Stagecoach Reservoir escapement . Two reservoirs in the upper Yampa River have established populations and Lake Catamount. Dam constructionandLake Catamount was completed in 1978Lake of northern pike: Stagecoach Reservoir on Lake Catamount. Dam construction on and Stagecoach Reservoir was constructed in 1989. Northern pike were 1st detected in Catamount was completed in 1978 and Stagecoach Reservoir was constructed in 1989. Stagecoachpike had been first detected in Stagecoach Reservoir in 1994, potentially from an Northern Reservoir in 1994, potentially from an illicit introduction, and then in Lake Catamount in 1995, then escapees from Stagecoach Reservoir escapees from Stagecoach illicit introduction, probably as in Lake Catamount in 1995, most likely as . Escapement is a lot more likely than. Escapement is for Lake Catamount for the reason that this isfor private reservoir Reservoir illicit introduction additional probably than illicit introduction a Lake Catamount GW-870086 Purity closed to this can be a access plus the priority on the lake’s management is often a rainbow lake’s for the reason that public private reservoir closed to public access and the priority with the trout (Oncorhynchus mykiss) fishery, (Oncorhynchus mykiss) fishery, to which an illicit northern management is often a rainbow trout to which an illicit northern pike introduction will be pike introdu.