Dr. Dana Winkelman and Dr. Kevin Bestgen, CSU; Kevin Thompson, CPW
Upper White River
Completed - Master's Thesis available
- To determine if species distribution and reproduction is related to temperature and flow.
- To collect information on basic life history traits for each of the three-species, especially spawning and rearing locations.
- To determine if the native suckers exhibit fidelity to the same spawning tributary over time.
Researchers attribute flannelmouth sucker, bluehead sucker, and roundtail chub (the "three-species") population declines and range shrinkage to human-caused environmental changes. For example, the construction of dams alters runoff patterns, retains sediment, changes water temperature regime and fragments fish populations. In the upper White River, populations of all of the three species are now isolated from three-species populations below Kenney Reservoir, but populate a portion of the river with a natural flow and temperature regime.
Therefore, CPW initiated a study to investigate the effects of flow and temperature patterns on three-species' use of spawning tributaries, fidelity to those tributaries and locations where the larvae live in a relatively intact system. Researchers marked fish using passive integrated transponder (PIT) tags to assess tributary use. Stationary antennae to detect the tags were installed in two spawning tributaries, and water temperatures were monitored at numerous locations in the White River and its tributaries.
The research team used these data to determine that spawning behavior and location was driven more by water temperature than by stream flow, and that PIT-tagged suckers exhibited moderate fidelity to a spawning tributary. Larvae of the native suckers were found from the inflow to Kenney Reservoir to around the confluence of Coal Creek upstream of Meeker. Larvae of roundtail chub were found from Kenney Reservoir to around the confluence of Piceance Creek. Timing of spawning overlapped considerably for the native suckers, but was later for roundtail chub. Coal Creek was determined to be an important spawning tributary and in many years will allow earlier spawning in this reach of the White River because it is warmer than the mainstem river during spawning season.