Kolob Reservoir to be drained due to illegally introduced fish; reward offered for information

Kolob Reservoir, looking northwest from the dam, Kolob Plateau, Utah, June 19, 2018 | File photo by Reuben Wadsworth, St. George News

ST. GEORGE – Wildlife officials are offering a reward to find out who illegally stocked Kolob Reservoir with fish that pose a threat to endangered Virgin River species.

The Utah Division of Wildlife Resources posted an advisory on Facebook Friday alerting the public that three species of fish – yellow perch, green sunfish and bluegill – had been illegally stocked in the reservoir.

These species … pose a substantial threat to the endangered fish species that live downstream in the Virgin River,” the Facebook post states.

Because of the danger to the endangered Virgin River fish – the Virgin River chub and woundfin – officials will be draining Kolob Reservoir this fall and treating it with rotenone to remove all fish.

Rotenone, a natural product derived from the roots of South American plants, is specifically toxic to gilled organisms because it interrupts oxygen uptake from the water at the cellular level. It also completely decomposes without leaving any harmful residue.

The Virgin River and other Southern Utah waters have been subject to rotenone treatment in recent years to exterminate invasive species that threaten native species populations.

The Utah DWR on Friday increased the bag and possession limit at the Kolob Reservoir to eight trout. There is no size restriction and bait can also be used.

Anyone with information about who illegally introduced the perch, sunfish and bluegill into the reservoir is asked to call the UTiP hotline at 1-800-662-3337.

“We’re offering a reward of up to $3,000 for details that lead to the prosecution of those responsible for illegally introducing fish to Kolob,” the DWR Facebook post states.

Email: [email protected]

Twitter: @MoriKessler

Copyright St. George News, SaintGeorgeUtah.com LLC, 2018, all rights reserved.

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  • bikeandfish September 1, 2018 at 12:56 pm

    These avocational introductions cost the state and tax payers millions. But I’ll enjoy increased bag limit and removal of the slot for the remainder of the season. Time to fill the freezer since they will all be killed anyways.

  • tazzman September 1, 2018 at 4:34 pm

    What a mess. Hopefully they catch the perp(s).

  • chris keele September 1, 2018 at 6:08 pm

    i am reminded of a conversation I had with a biologist that worked for the State dept. of wildlife resources quite a few years ago, when I asked him about a group of lakes I had experienced fishing in which some were very well stocked and some were seemingly void of fish, and to my questions he answered ” the fish sometimes arrive on the feet and wings of ducks in the form of fertilized eggs picked up at some other body of water” maybe there are no human perpetrators involved, makes me wonder sometimes.

  • Utahguns September 1, 2018 at 6:57 pm

    The same situation has occurred at Baker Reservoir near the community of Central, 27 miles North on Highway 18.

    The pervasive species of fish that have been introduced into this body of water are GOLDFISH (ie: exotic carp)
    I personally witnessed schools of this fish in the lake that are multiple cubic yards in size.

    These fish breed prolifically and disrupt the ecosystem. They scour the bottom of lakes for food, vacuuming up practically everything in sight and leaving very little behind for the native or planted forage fish. They can even eliminate frogs from an area by eating tadpoles.

    Now it looks like the lake will have to be drained to eliminate the goldfish….. All because of low-foreheaded individuals getting rid of their ornamental livestock.
    The 100,000 German Brown trout that were planted last year will suffer the biggest loss… so will sport fishermen and campers that frequent the area.

    • mesaman September 1, 2018 at 8:38 pm

      Sadly, it is the vast number of law-abiding fishermen who will suffer in both cases. I can only hope karma will consider a reasonable revenge in the name of those who legitimately fish the state’s waters.

    • Anejo September 2, 2018 at 12:50 pm

      ~ The same situation has occurred at Baker Reservoir near the community of Central, 27 miles North on Highway 18.

      I’m in full agreement with you, sir!

      Baker is my local water. My last 4 outings here (since the water level dropped from ‘reservoir’ to muddy puddle’) we have caught nothing but bluegill and had two of the exotic goldfish. The latter being a pure fluke, of which I’m certain. As you posted I have also witnessed schools of these fish rising at sundown and churning around just under the surface.

      I cannot understand the mentality of a person that walks past the numerous “Please Do Not Introduce Fish Into This Lake” signs and releases the contents of their aquarium. While I can accept there is a possible introduction from natural sources it’s an insult to the reader to say that is a mitigating factor in our local waters. It’s the same mentality where someone thinks starting a campfire in the backwoods in July and flying a drone or 12 over an active wildfire is a ‘cool’ idea.

  • Jeannette September 2, 2018 at 12:35 am

    Could be eggs on birds or carried in gear unknowingly. What about airplane water drops during fires?

    I just can’t go with the idea of perps putting immigrant fish in waters. If so … hope they get some leads.

    In Yellowstone a lot of years back, the Dept of Fish and Game intentionally planted non-native fish in waters, and the immigrants took over. As of a few years back, it was made public and remedies were put in place to get rid of the fish. Wonder if that wrong ever was made right?

    • An actual Independent September 2, 2018 at 11:37 am

      It’s not like they’re taking water FROM the fire and dropping it INTO a lake. The fish lost in those operations are not reproducing in the lake. They are charcoal grilled fish.

  • Badshitzoo September 2, 2018 at 12:06 pm

    “Illegally stocked” ? Too what end? I’ve been fly fishing Kolob for 30 yrs. This is a “Death penalty” offense if true. So, unless someone is trying to piss me off, I don’t see a reason ? A lot of people say Bluegill are the best tasting fish, but you need a lot for a meal. I could buy that if it was done in town; but who’s drivin up to Kolob everytime they want a plate full ? Additionally, they are shallow water fish that thrive in 60 – 80 degree waters, not high mountain lakes that freeze reliably every year. The only thing that might explain this story is a “misguided intentions” explanation ??? These fish eat crustaceans. Maybe some very misguided individual was thinking they were protecting Kolob from the invasive snail species hitching rides on boat hulls from lake to lake ? That’s what Riggs & Murtaugh call “Thin”.

  • Badshitzoo September 2, 2018 at 5:38 pm

    As if this place don’t suck bad enough for Trout fishing!

  • Striker4 September 2, 2018 at 8:22 pm

    If its being taken over by illegals you better call Donald Trump ….cuz he will drain the swamp for ya

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