Rotenone treatment to take place at Duck Fork Reservoir
Anglers have about two weeks left to take advantage of liberalized fishing regulations allowing a daily bag and possession limit of 16 trout and use of bait at Duck Fork Reservoir and its tributaries.
Beginning September 23, the Utah Division of Wildlife Resources will begin treating the waters with the natural chemical rotenone to eliminate existing fish populations. Rotenone will be applied over a period of about three days. Because rotenone biodegrades fairly quickly, restocking of Duck Fork Reservoir with fish should be possible by late October. Opportunities for anglers to harvest fish again will resume in 2003.
The purpose of removing fish from Duck Fork Reservoir and its tributaries is to replace Yellowstone cutthroat trout, a nonnative subspecies, with rare native Colorado River cutthroat trout (CRCT).
There are two purposes for introducing the native subspecies of cutthroat trout. First, the introduction is part of a multi-agency plan to improve the status of CRCT and prevent it from becoming federally listed as threatened or endangered. Second, it will allow production of cutthroat trout for sport fish stocking purposes. In recent years, no cutthroat trout have been available for stocking in southeastern Utah.
Duck Fork Reservoir will become what DWR calls a brood lake. Mature fish will be annually trapped in Duck Fork Creek when they migrate into that tributary during the spawning season. Eggs will be extracted, fertilized, and transported to a hatchery for rearing large numbers of fish for stocking. Stocking will allow DWR to expand the distribution of CRCT into a larger portion of its historic range.
A brood population of genetically pure fish cannot be developed without first removing all fish which might pose a threat of hybridization. In the case of Duck Fork Reservoir, the Yellowstone race, if not removed, would hybridize with the soon-to-be released Colorado River race. This would destroy the genetic purity of the CRCT population. Rotenone use is the only effective means of completely eliminating Yellowstone cutthroat trout.
The DWR believes that the public will enjoy opportunities to fish for CRCT. This subspecies of cutthroat trout is more colorful than the Yellowstone cutthroat trout and has the potential to grow as large or larger.
Along with CRCT, the DWR plans to restock tiger trout in Duck Fork Reservoir. This will give anglers a popular species they can harvest while CRCT are protected. Within a few years, fishing should be as good or better than it has ever been.
Questions may be directed toward regional aquatic program manager Louis Berg at 435-636-0268 or email at email@example.com.