DAVE & DUJANOVIC

How someone’s pet goldfish destroyed an entire ecosystem at Maple Lake

Oct 9, 2018, 2:46 PM | Updated: 2:51 pm
Gold Fish At Maple Lake...
Goldfish have infested the waters at Maple Lake. (Mark Hadley, Utah Division of Wildlife Resources)
(Mark Hadley, Utah Division of Wildlife Resources)

Maple Lake has become infested with an invasive species: goldfish.

The Utah Division of Wildlife Resources says that the lake has become so overrun with goldfish that it’s become a crisis. The goldfish are polluting the water and using up so much of the food that the trout in the lake are dying off.

The only solution now, they say, is to wipe out every living animal in the lake and start over again.

Biologist Chris Crockett sat down with Dave Noriega and his special guest Amy Donaldson on KSL’s Dave & Dujanovic to talk about how a lake in Utah became overrun with fish we normally think of as pets — and just how hard it’s going to be to fix it.

A well-intentioned disaster

Maple Lake goldfish

Maple Lake. (Photo: Mark Hadley, Utah Department of Wildlife Resources)

The infestation didn’t happen naturally. Goldfish don’t normally live in the lakes of the western United States, and it’s highly unlike that any pathways could have sent them into Maple Lake.

Instead, Chris Crockett says, the infestation most likely started with someone setting their pet goldfish free.

“I suspect that someone though they were doing their pet goldfish a favor,” Crockett says.

That act of mercy brought on an ecological disaster. Goldfish reproduce at extremely high rates; before long, they’d taken over the entire lake.

By 2015, anglers were reporting seeing goldfish in the water; and, not long after, they started seeing goldfish that had grown up to seven inches long. The fish just kept getting bigger and more plentiful after that, and now there are so many of them that anglers are having trouble keeping them off of their lines.

The goldfish now have such a huge presence in Maple Lake that the trout that normally fill its waters are starving to death. They’ve also muddied up the waters, making the lake completely inhospitable to other forms of animal life.

A drastic solution

Maple Lake goldfish

Since the Maple Lake disaster, the Utah Division of Wildlife Resources has started a “Don’t ditch a fish” campaign. (Utah Division of Wildlife Resources)

At this point, Crockett says, there are no small steps that could clear the goldfish out.

In the past, conservation experts have been able to get goldfish out of other lakes by introducing a natural predator. In Maple Lake, however, the infestation is too wide-spread and the goldfish have grown too large for any controllable predator to take them out.

Instead, Crockett’s team is clearing the lake out altogether.

They have begun draining as much of the five-acre lake as they can. Now that the lake is significantly lower, they’re moving onto the next step: killing the fish inside with a chemicals called rotenone.

Next steps for Maple Lake

The chemical should wipe the goldfish of Maple Lake out completely, then break down within three days. After keeping the lake blocked off for 14 days, Crockett and his team will test the water to make sure it’s safe again. Once it is, they plan on refilling it with trout.

In the meantime, Crockett says that the rotenone water would be almost entirely harmless to humans, even if someone were to sneak into the blocked-off lake and drink the water.

“A person my size would have to drink about 100 gallons to have any sort of negative effect,” Crockett says.

Most other animals, likewise, should not be harmed. “A duck would have to drink about 7 or 8 gallons in one sitting to have an effect.”

After an expensive and drastic response, Maple Lake is expected to go back to normal. Crockett reminded our listeners, though, to keep their goldfish in their fish bowls.

More to the story

If you missed Dave & Dujanovic today on KSL Newsradio, you can still catch our interview with Chris Crockett on the Dave & Dujanovic podcast.

Dave & Dujanovic can be heard weekdays from 9 a.m. to noon on KSL Newsradio. Users can find the show on the KSL Newsradio website and app, as well as Apple Podcasts and Google Play.

Listen on Apple PodcastsListen on Google Play Music

Today’s Top Stories

Dave & Dujanovic

FILE - This Friday, Feb. 16, 2018, file photo shows application icons from left, Facebook, Facebook...
Curt Gresseth

Expert gives tips on conquering your downward social media scroll

Are you addicted to the social-media scroll? An expert weighs in on what you can do to slow the scroll.
4 days ago
High water in the Gardiner River along the North Entrance to Yellowstone National Park in Montana, ...
Curt Gresseth

Be ready for flash flooding: Expert shares advice

An expert with the Utah Division of Emergency Management shares his expertise and crucial tips on how to be ready for flash flooding when you are in a vehicle or at home.
5 days ago
salt lake mayorMendenhall guns...
Curt Gresseth

After NY law is struck down, two Utah experts sound off on gun rights

Two advocates on either side of the gun-control vs. gun rights debate sound off on the Supreme Court's 6-3 ruling to expand the right to carry a firearm in public.
10 days ago
Salt Lake County Search and Rescue safely rescued a hiker  out of the Lisa Falls trail on Friday.
P...
Curt Gresseth

Search and rescue expert has tips for hikers

Before you head out on your hike, take someone with you, tell somebody where you are going and when you plan to return. Those are just a few words for hikers from an expert on search and rescue.
11 days ago
A fire engine is seen as the Sheep fire burns in Wrightwood, Calif., Monday, June 13, 2022. (AP Pho...
Curt Gresseth

Be Ready Utah: What to do when wildfires close in on your home

Will you be ready if wildfires close in on your home? A survivor of a wildfire shares his experience and an expert shares tips and advice.
12 days ago
(Photo Credit: CNN/Shutterstock)...
Curt Gresseth

What is behind rising credit-card debt? Financial expert weighs in.

A national expert explains the sudden rise in credit-card debt in April and what you can do to lower your monthly payments.
18 days ago

Sponsored Articles

Tax Harassment...
Jordan Wilcox

The best strategies for dealing with IRS tax harassment | You have options!

Learn how to deal with IRS tax harassment. This guide will teach you how to stop IRS phone calls and letters, and how to handle an IRS audit.
spend a day at Bear Lake...
Bear Lake Convention and Visitors Bureau

You’ll love spending the day at Bear Lake | How to spend a day at Bear Lake

Bear Lake is a place that needs to be experienced. Spend a day at Bear Lake.
Curb Appeal...
Price's Guaranteed Doors

How to have the best of both worlds for your house | Home security and curb appeal

Protect your home and improve its curb appeal with the latest security solutions like beautiful garage doors and increased security systems.
Prescription opioids can be disposed of during National Prescription Take Back Day...
Know Your Script

Prescription opioid misuse | How to protect your family from the opioid epidemic

Studies have shown that prescription opioid misuse has increased since COVID-19. So what do you need to know about these opioids?
national heart month...
Intermountain Healthcare

National Heart Month: 5 Lifestyle Changes to Make Today to Keep You Heart Healthy

Heart disease is the leading cause of death for both men and women. One person dies every 36 seconds in the United States from cardiovascular disease
Joseph Smith Memorial Building...
Temple Square

The Joseph Smith Memorial Building is an icon of Salt Lake City | Why hosting an event at this beautiful location will make you a hero this year

Here's why hosting an event at the iconic Joseph Smith Memorial Building in downtown Salt Lake City will make you a hero this year.
How someone’s pet goldfish destroyed an entire ecosystem at Maple Lake