Boulder Mountain Treatment Plan

The Utah Division of Wildlife Resources, in cooperation with the Dixie National Forest and Bureau of Land Management, is developing a plan to improve sport fishing on Boulder Mountain in southern Utah. Under the plan, which would be completed over a six-year period, 18 lakes and three associated stream systems would be treated with the fish toxicant rotenone. The waters would then be restocked with trout, including rainbow, tiger, splake and locally native cutthroat.

The DWR said the plan was prompted by public concern and studies conducted by fisheries biologists. Specifically, during the 1998 Regional Advisory Committee (RAC) meetings, the public expressed concern over the decline of many of the Boulder Mountain fisheries. The DWR was asked by RAC members to investigate the situation and recommend corrective action. As a result, 27 lakes were surveyed in 1999; 18 were found to contain either stunted brook trout populations, non-native redside shiners and/or non-native mountain suckers.

The removal of these populations is necessary before angling can be improved at individual waters. At the same time, the proposed action would provide a secondary benefit by establishing conservation populations of native trout at several locations.

To enhance these fisheries, the DWR proposes to treat the lakes and stream systems with rotenone. All fish would be temporarily eliminated from target waters. To ensure complete removal of target fish, the waters would be retreated on subsequent years. Where necessary, rotenone would be detoxified during the treatments at the lower end of project areas to prevent downstream impact. Each body of water would be restocked as treatment is completed.

Rotenone is a natural chemical used in the agricultural and livestock industries. At the concentrations used to kill fish, it is harmless to crops, livestock, people, other mammals or birds. It is approved for use as a fish toxicant by the EPA and has been used widely in the United States since the 1930s. Waters used as municipal water supplies have been treated with rotenone in at least seven states, including Utah, with no harmful effects. Fish killed by rotenone are not cleared for human consumption and salvage of treated fish by the public is not permitted.

The DWR proposes to construct two fish migration barriers, consisting of small rock structures that create a drop of approximately five feet, at the lower end of treated sections to prevent re-colonization of treated waters by eliminated fish species. The barriers, constructed outside roadless areas, will be made of local rock materials and require limited machinery and will not impound stream flows.

Implementation of these projects is scheduled over a six-year period following completion of an Environmental Assessment, if one is needed, and formal decision by the appropriate land management agency. Waters that now support a low level of sport fish recreation will be treated first, while declining waters that still provide some recreation will be treated near the end of the six-year period. The following waters are proposed for treatment and enhancement, and are listed in order of treatment priority:

Solitaire Lake, Wayne County

Now contains: severely stunted brook trout.

Treatment area: 29 acre-feet of water and several spring-fed inlets. The only outflow from Solitaire goes sub-surface just downstream of the lake; no detoxification would be required.

Restock: a trout species that could be more easily managed.

Round Willow Bottom Reservoir, Garfield County

Now contains: stunted brook trout.

Treatment area: 62 acre-feet of reservoir, approximately 200 meters of inlet stream, 1/4 mile of diversion stream that connects Long Willow Bottom and Round Willow Bottom, and 3.5 miles of Twitchell Creek. Connected to Long Willow Bottom Reservoir, which contains Yellowstone cutthroat trout. A migration barrier would be constructed on Twitchell Creek just above its confluence with North Creek, with detoxification just below the barrier. The two reservoirs would be treated simultaneously because of their close proximity and similar management.

Restock: Colorado River cutthroat trout.

Long Willow Bottom, Garfield Country

See previous paragraph on Round Willow Bottom Reservoir.

Pine Creek Reservoir, Wayne County

Now contains: stunted brook trout.

Treatment area: 14.1 acre-feet of reservoir, approximately 1/2 mile of inlet and tributary streams; also would remove brook trout, rainbow trout and brown trout from over 7.5 miles of Pine Creek, with a migration barrier construction just above the King ranch near the Egan hatchery.

Restock: Colorado River cutthroat trout.

Short Lake, Garfield County

Now contains: stunted brook trout.

Treatment area: seven acre-feet of lake, several spring inlets and approximately 1/4 mile of outlet stream. Treated water would be detoxified below a natural barrier situated just above the outlet stream’s confluence with the east fork of Boulder Creek.

Restock: Colorado River cutthroat trout.

Rob Reservoir, Garfield County

Now contains: stunted brook trout.

Treatment area: 5.2 acre-feet of reservoir, two spring creek tributaries and over five miles of Center Creek. This reservoir is associated with five miles of stream habitat. Treated water would be detoxified below the natural barriers just above the Center Creek ranch, near Antimony.

Restock: Rob Reservoir has been selected for the introduction of native Bonneville cutthroat trout.

Bullberry Lake #1 (South), Wayne County

Now contains: stunted brook trout.

Treatment area: 4.1 acre-feet of lake and approximately 1/2 mile of Bullberry Creek. Should be treated in conjunction with Bullberry Lakes 2, 3 and 4 because they are directly connected.

Restock: a trout species that can be managed by stocking.

Bullberry Lake #2, Wayne County, directly connected to Bullberry #1 and #3

Now contains: stunted brook trout.

Treatment area: lake and a short section of stream.

Restock: a trout species that can be managed by stocking.

Bullberry Lake #3, Wayne County, directly connected to Bullberry #2 and #4

Now contains: stunted brook trout.

Treatment area: the lake and a short section of stream.

Restock: a trout species that can be managed by stocking.

Bullberry Lake #4 (South), Wayne County

Now contains: severely stunted brook trout.

Treatment area: 7.2 acres-feet of lake and approximately 200 meters of an outlet stream that is a tributary to Bullberry Creek.

Restock: a trout species that can be managed through stocking.

Heart Lake (North), Wayne County

Now contains: severely stunted brook trout.

Treatment area: 1.4 acre-feet of water. This lake has no outflow and would not require detoxification.

Restock: a trout species that can be more easily managed.

Heart Lake (South), Wayne County

Now contains: severely stunted brook trout.

Treatment area: 1.3 acre-feet of water. This lake has no outflow and would not require detoxification.

Restock: a trout species that can be more easily managed.

Blue Lake (North Creek), Garfield County

Now contains: severely stunted brook trout.

Treatment area: six acre-feet of water and approximately 100 meters of spring-fed inflow. There are no outflows and detoxification would not be necessary.

Restock: a trout species that can be managed by stocking.

Fish Creek Reservoir, Wayne County

Now contains: stunted brook trout and mountain suckers.

Treatment area: 232 acre-feet of reservoir, several spring-fed inlets and approximately 100 meters of Fish Creek that connects to Beaver Dam Reservoir. Fish Creek Reservoir would be treated in conjunction with Beaver Dam Reservoir because of their close proximity.

Restock: a trout species or community of trout species that can be managed by stocking.

Beaver Dam Reservoir, Wayne County

Now contains: brook trout and mountain suckers.

Treatment area: 73 acre-feet of reservoir, 2 spring-fed inlets and approximately 100 meters of Fish Creek. This reservoir has produced excellent fishing in the past but the average size of the brook trout is now declining and will continue to decrease as it receives migrating fish from Fish Creek Reservoir.

Restock: a trout species or community of trout species that can be managed by stocking.

Oak Creek Reservoir, Garfield County

Now contains: stunted brook trout.

Treatment area: 920 acre-feet of reservoir, several spring-fed inlets and approximately 100 meters of Oak Creek.

Restock: a trout species or community of trout species that can be more easily managed.

Blue Lake (Griffin Top), Garfield County

Now contains: brook trout and redside shiners.

Treatment area: 80 acre-feet of water to remove shiners and re-establish brook trout in a non-competitive environment. Because there are no surface outflows to this lake no detoxification would be required.

Restock: a trout species whose numbers can be managed by stocking.

Donkey Lake, Wayne County

Now contains: stunted brook trout.

Treatment area: 275 acre-feet of lake. These trout may be controlled by water level manipulations at the reservoir. If such manipulations are unsuccessful, chemical treatment will be employed.

Restock: a trout species or community of trout species that can be more easily managed.