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

The habitat occupied by native cutthroat trout or officially designated as Gold Medal or
Wild Trout fisheries is limited. Much of the current and potential stream and lake habitat for
native cutthroats occurs in headwater drainages, and the use of native cutthroats as the primary
trout species for management in these headwater drainages appears feasible from a conservation
perspective. However, even with the expansion of native cutthroat waters to full potential, the
resource base for these species would represent only 10% of the coldwater stream miles and 1%
of the coldwater lake surface area available. Fisheries for these species should focus on catch-
and-release and limited-harvest regulations.
Threats to native cutthroat from hybridization with nonnative salmonids, overharvesting
from angling, and degradation of habitat can be dealt with using known fish management
strategies, legal protection of instream flows, and water quality regulations. Protection from WD
stocking has been provided through DOW policy, which defines native cutthroat habitat and high-
quality wild trout fisheries, and through the immediate application of stocking restrictions to
protect populations from exposure to the parasite. Continued establishment of new populations
of native cutthroat trout provides insurance against potential losses to WD.
Recreation
Fishery resources in Colorado are characterized by their management type (using the
DOW's Categorization System) into Intensive Use (catchable trout stocking), Optimum Use (no
stocking, or cold- and warmwater fry, fingerling, or subcatchable hatchery fish), and Special Use
(little or no stocking). Fishing recreation days, fish catch, and fish stocking requirements
associated with each category were estimated for the base year 1992. More recently, trout
stocking has been changed to prevent the spread of the WD parasite into protected habitats. As a
result, estimated fishing recreation days and their statewide distribution have likely been
significantly altered. This change, along with the decision to reduce WD+ catchable trout
stocking by 1.3 million fish in 1997, could further reduce recreation days on the west slope by
500,000 recreation days as compared with 1992, while east slope recreation days could decline to
1992 levels. Because the state is perilously close to losing negative WD status on its remaining
fry and fingerling production units, serious losses of fishing recreation could also occur in habitats
managed for Optimum Use.
A number of options could be considered to mitigate the loss of recreation days resulting
from reductions in WD+ stocking. Balancing the stocking of WD- and WD+ trout in 1997 can
provide some short-term, but limited, relief to fishing recreation losses that the state is now
experiencing. Increasing recreation in warmwater fisheries holds some promise through the
acquisition of new access, improvement of angler facilities, enhancement of habitat at existing
lakes, and an increase in the stocking levels of WD+ catchable trout in nontraditional warmwater
habitats. Emphasizing wild trout management in Coldwater lakes may have only limited potential
because of the near total dependency on hatchery-reared trout to sustain fishing recreation in
those habitats. On the other hand, there is some potential to switch to a greater reliance on wild
trout management (including native cutthroats). The tradeoff is a loss of recreation days or some
vi