8057

• UCREFRP Catalog Number: 8057
• Author: Bennett, J. R., D. A. Krieger, T. P. Nesler, L. E. Harris and R. B. Nehring.
• Title: An Assessment Of Fishery Management And Fish Production Alternatives To Reduce The Impact Of Whirling Disease In Colorado.
• USFW Year: 1996.
• USFW - Doc Type: Denver, Colorado.
• Copyright Material: NO

Threats and Protection Options
Populations of native cutthroat trout, Wild Trout fisheries, and Gold Medal fisheries are
protected by stocking restrictions, fishing closures, harvest and gear restrictions, and stream
barriers to fish passage. These approaches have proven effective in reducing the threat of
hybridization in native cutthroat populations, and overharvest from angling. Threats due to
depletion of the instream flow regime are reduced through filings for minimum instream flow
rights with the Colorado Water Conservation Board (CWCB 1996). Currently, 7,255 stream
miles in 1,222 stream segments are protected by decree over the seven water divisions (S.
Platte/Republican, Arkansas, Rio Grande, Gunnison/San Miguel, Colorado, Yampa/White, and
San Juan/Dolores). An additional 727 stream miles in 104 stream segments are not yet decreed.
State water quality standards exist to protect coldwater fishery resources from pollution and
degradation. Many of these potential threats are dealt with by DOW using either formal protocols
in state law or established management solutions to maintain the integrity of these fishery
resources. Further protection for native cutthroats is contained in the Endangered Species Act,
Clean Water Act, NEPA, and other federal mandates such as the U.S. Forest Service Sensitive
Species Program.
Unlike the threats and protection options just discussed, the threat of WD to native
cutthroat and wild trout populations seems less amenable to solutions since it is perceived as a
pathogen "on the loose" in Colorado waters that is not readily controlled by conventional or
existing approaches. The first step in the protection of native and wild trout from WD is
appropriately found among the stocking restrictions in the DOW WD Policy. Even during the
development phase of the policy, delineation of native cutthroat habitat and high quality wild trout
fisheries to be protected, and immediate implementation of stocking restrictions to protect these
waters by DOW biologists occurred. At the end of 1995, no cutthroat trout population had tested
positive for the MC pathogen. However, subsequent monitoring of protected waters is required
to evaluate the effectiveness of this approach.
Further restrictions in stocking have been proposed as a desirable protective measure for
existing trout fisheries and as a containment measure to minimize the spread of WD. The most
extreme,! short-term protective/containment measure available to DOW is to eliminate all
production of WD+ trout from state hatcheries. This would dramatically decrease stocking
options and associated recreation days. The impact would be abrupt and certain to create
negative reaction among potentially affected interests. This alternative, therefore, is considered
inadvisable. The consequences of less severe stocking restrictions and the use of WD+ hatchery
production for recreation opportunities are discussed in the Recreation Section.
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