Geology topics

Research about Cache la Poudre River

Source-linked reports with geographic coverage including Cache la Poudre River.

6 recordsLinked to original sources

USGS2019

Designing flows to enhance ecosystem functioning in heavily altered rivers

More than a century of dam construction and water development in the western United States has led to extensive ecological alteration of rivers. Growing interest in improving river function is compelling practitioners to consider ecological restoration when managing dams and water extraction. We developed an Ecological Response Model (ERM) for the Cache la Poudre River, northern Colorado, USA, to illuminate effects of current and possible future water management and climate change. We used empirical data and modeled interactions among multiple ecosystem components to capture system-wide insights not possible with the unintegrated models commonly used in environmental assessments. The ERM results showed additional flow regime modification would further alter the structure and function of Poudre River aquatic and riparian ecosystems due to multiple and interacting stressors. Model predictions illustrated that specific peak flow magnitudes in spring and early summer are critical for substrate mobilization, dynamic channel morphology, and overbank flows, with strong subsequent effects on instream and riparian biota that varied seasonally and spatially, allowing exploration of nuanced management scenarios. Instream biological indicators benefitted from higher and more stable base flows and high peak flows, but stable base flows with low peak flows were only half as effective to increase indicators. Improving base flows while reducing peak flows, as currently proposed for the Cache la Poudre River, would further reduce ecosystem function. Modeling showed that even presently depleted annual flow volumes can achieve substantially different ecological outcomes in designed flow scenarios, while still supporting social demands. Model predictions demonstrated that implementing designed flows in a natural pattern, with attention to base and peak flows, may be needed to preserve or improve ecosystem function of the Poudre River. Improved regulatory policies would include preservation of ecosystem-level, flow-related processes and adaptive management when water development projects are considered.

Colorado↗

USGS2015

Brown Trout removal effects on short-term survival and movement of Myxobolus cerebralis-resistant rainbow trout

Following establishment of Myxobolus cerebralis (the parasite responsible for salmonid whirling disease) in Colorado, populations of Rainbow Trout Oncorhynchus mykiss experienced significant declines, whereas Brown Trout Salmo trutta densities increased in many locations across the state, potentially influencing the success of M. cerebralis -resistant Rainbow Trout reintroductions. We examined the effects of Brown Trout removal on the short-term (3-month) survival and movement of two crosses of reintroduced, M. cerebralis -resistant Rainbow Trout in the Cache la Poudre River, Colorado. Radio frequency identification passive integrated transponder tags and antennas were used to track movements of wild Brown Trout and stocked Rainbow Trout in reaches where Brown Trout had or had not been removed. Multistate mark–recapture models were used to estimate tagged fish apparent survival and movement in these sections 3 months following Brown Trout removal. A cross between the German Rainbow Trout and Colorado River Rainbow Trout strains exhibited similar survival and movement probabilities in the reaches, suggesting that the presence of Brown Trout did not affect its survival or movement. However, a cross between the German Rainbow Trout and Harrison Lake Rainbow Trout exhibited less movement from the reach in which Brown Trout had been removed. Despite this, the overall short-term benefits of the removal were equivocal, suggesting that Brown Trout removal may not be beneficial for the reintroduction of Rainbow Trout. Additionally, the logistical constraints of conducting removals in large river systems are substantial and may not be a viable management option in many rivers.

Colorado↗

USGS2014

Raft and floating radio frequency identification (RFID) antenna systems for detecting and estimating abundance of PIT-tagged fish in rivers

Portable radio frequency identification (RFID) PIT tag antenna systems are increasingly being used in studies examining aquatic animal movement, survival, and habitat use, and their design flexibility permits application in a wide variety of settings. We describe the construction, use, and performance of two portable floating RFID PIT tag antenna systems designed to detect fish that were unavailable for recapture using stationary antennas or electrofishing. A raft antenna system was designed to detect and locate PIT-tagged fish in relatively long (i.e., ≥10 km) river reaches, and consisted of two antennas: (1) a horizontal antenna (4 × 1.2 m) installed on the bottom of the raft and used to detect fish in shallower river reaches (<1 m), and (2) a vertical antenna (2.7 × 1.2 m) for detecting fish in deeper pools (≥1 m). Detection distances of the horizontal antenna were between 0.7 and 1.0 m, and detection probability was 0.32 ± 0.02 (mean ± SE) in a field test using rocks marked with 32-mm PIT tags. Detection probability of PIT-tagged fish in the Cache la Poudre River, Colorado, using the raft antenna system, which covered 21% of the wetted area, was 0.14 ± 0.14. A shore-deployed floating antenna (14.6 × 0.6 m), which covered 100% of the wetted area, was designed for use by two operators for detecting and locating PIT-tagged fish in shorter (i.e., <2 km) river reaches. Detection distances of the shore-deployed floating antenna were between 0.7 and 0.8 m, and detection probabilities during field deployment in the St. Vrain River exceeded 0.52. The shore-deployed floating antenna was also used to estimate abundance of PIT-tagged fish. Results suggest that the shore-deployed floating antenna could be used as an alternative to estimating abundance using traditional sampling methods such as electrofishing.

Colorado↗

USGS2007

Simulation of flow and habitat conditions under ice, Cache la Poudre River - January 2006

The U.S. Forest Service authorizes the occupancy and use of Forest Service lands by various projects, including water storage facilities, under the Federal Land Policy and Management Act. Federal Land Policy and Management Act permits can be renewed at the end of their term. The U.S. Forest Service analyzes the environmental effects for the initial issuance or renewal of a permit and the terms and conditions (for example, mitigations plans) contained in the permit for the facilities. The U.S. Forest Service is preparing an environmental impact statement (EIS) to determine the conditions for the occupancy and use for Long Draw Reservoir on National Forest System administered lands. The scope of the EIS includes evaluating current operations and effects to fish habitat of an ongoing winter release of 0.283 m3 /s (10 ft3 /s) from headwater reservoirs as part of a previously issued permit. The field conditions observed during this study included this release. The U.S. Forest Service entered into an interagency agreement (05-IA-11021000-030) with the U.S. Geological Survey (USGS) Fort Collins Science Center to perform analysis of fish habitat and flow relationships in the Cache la Poudre River during winter ice-over conditions using a twodimensional hydrodynamic model. The U.S. Forest Service selected the Fort Collins Science Center for this task because of their expertise in developing two-dimensional hydraulic models for habitat modeling applications. This report transmits model results to the U.S. Forest Service to analyze the effects of alternative flow scenarios at a site on the mainstem Cache la Poudre River in Larimer County, Colorado, near Kinikinik (40° 42' 44.16" N. lat, 105° 44' 30.70" W. log), as shown in figure 1. It will be used in pending environmental analyses and decisions for the occupancy and use of the Arapaho-Roosevelt National Forest by water storage facilities. The water management scenarios of interest in this study are related to releasing water from Chambers and Barnes Meadows Reservoirs, based on the assumption that winter flow augmentation can increase potential fish habitat. Figure 2 shows the relationship between Chambers, Barnes Meadows, and Long Draw Reservoirs. At the time this study was proposed, existing flow simulation results showed that the channel constraints imposed by existing artificial low-head dikes would have little or no effect on the hydrodynamics of the river at the low flow levels that were to be evaluated. The Kinikinik study site contains deep pools, riffles, and runs. This diversity of habitat types made it ideal for assessing the effects of altered flow on fish habitat under ice in the main stem Cache la Poudre River. Thus, the Kinikinik site was selected for this study of winter habitat conditions. The preexisting topographic and hydrologic data collected at this site enabled data collection efforts for this study to focus on describing streamflow and ice cover during the winter months. A two-dimensional hydrodynamic model, River2D (Steffler and Blackburn, 2002), was used to simulate flow conditions under the ice cover that was observed January 24, 2006. The objectives of this study are (1) to describe the extent and thickness of ice cover, (2) simulate depth and velocity under ice at the study site for observed and reduced flows, and (3) to quantify fish habitat in this portion of the mainstem Cache la Poudre River for the current winter release schedule as well as for similar conditions without the 0.283 m 3 /s winter release.

Colorado↗

USGS2006

Application and testing of a procedure to evaluate transferability of habitat suitability criteria

A procedure designed to test the transferability of habitat suitability criteria was evaluated in the Cache la Poudre River, Colorado. Habitat suitability criteria were developed for active adult and juvenile rainbow trout in the South Platte River, Colorado. These criteria were tested by comparing microhabitat use predicted from the criteria with observed microhabitat use by adult rainbow trout in the Cache la Poudre River. A one-sided X 2 test, using counts of occupied and unoccupied cells in each suitability classification, was used to test for non-random selection for optimum habitat use over usable habitat and for suitable over unsuitable habitat. Criteria for adult rainbow trout were judged to be transferable to the Cache la Poudre River, but juvenile criteria (applied to adults) were not transferable. Random subsampling of occupied and unoccupied cells was conducted to determine the effect of sample size on the reliability of the test procedure. The incidence of type I and type II errors increased rapidly as the sample size was reduced below 55 occupied and 200 unoccupied cells. Recommended modifications to the procedure included the adoption of a systematic or randomized sampling design and direct measurement of microhabitat variables. With these modifications, the procedure is economical, simple and reliable. Use of the procedure as a quality assurance device in routine applications of the instream flow incremental methodology was encouraged.

Colorado↗

USGS2002

Factors influencing the distribution of Myxobolus cerebralis , the causative agent of whirling disease, in the Cache la Poudre River, Colorado

Oligochaetes, triactinomyxons (TAMs), and age-0 trout were sampled in the upper Cache la Poudre River, Colorado, to determine the distribution of Myxobolus cerebralis during 1997 and 1998. Densities of the intermediate host, the oligochaete Tubifex tubifex , were 3.5 orders of magnitude higher in the M. cerebralis -infected Poudre Rearing Unit (PRU) trout rearing ponds than at any of the river sampling reaches. Oligochaetes, including T. tubifex, were rare in the river (1 oligochaete m -2 ), except in a few stream side alcoves and eddies (50 oligochaete m -2 ). Species composition of oligochaetes in the river reaches was more diverse than in the PRU. Tubifex tubifex constituted 50% or less of the oligochaete community in the river and 98% in the PRU. Infection rates of T. tubifex were 1% in the area above the PRU, 2% in the PRU, and 6% below the PRU. An increased M. cerebralis intensity of infection in age-0 trout below the PRU could not be attributed entirely to the high numbers of TAMs in its effluent (3.7 TAMs l -1 ). Low densities of TAMs ranging from 0 to 0.2 TAMs l -1 were found in the river reaches, yet nearly all of the age-0 trout were infected soon after emergence. This suggests that very few TAMs, as measured by filtration, need be present in the water column to bring about infection in the majority of trout present. This also indicates that the parasite can persist and potentially cause reduced juvenile trout recruitment in cold, oligotrophic, sediment poor, high-gradient streams.

Colorado↗