Did you illegally dump an exotic catfish into the Animas River? If so, officers with Colorado Parks and Wildlife would like to have a quick conversation with you.
“That is such a huge, huge problem,” said Jim White, an aquatic biologist with CPW. “Not just locally, but nationwide, worldwide. People release fish, thinking they are doing a good thing, and it ends up having horrible ramifications for native fish.”
Last week, a Durango resident walking along the Animas River near 29th Street noticed an unusual sight along the shore – a dead armored catfish – and contacted CPW wildlife officers.
The armored catfish is from South America, and is typically kept in aquariums to help eat off the algae that accumulates on the glass. White believes someone had the fish as a pet, it got too big and the person released it into the Animas River.
“Ignorantly,” White said.
But alas, the armored catfish, which evolved in warm waters, likely couldn’t survive the winter in the Animas River, where water temperatures dip down to 40 degrees.
“They can’t tolerate that,” White said.
Illegally stocked non-native fish have been an issue that has plagued the American West’s rivers and streams ever since settlers first arrived in the 1800s. Now, the dynamics of entire river ecosystems have changed, irreparably.
The channel catfish (different than the armored catfish found in the Animas), for instance, does live within the Colorado River system. For years, millions of dollars have been spent trying to restore these native species on the lower San Juan River, which in part, involves removing other catfish and invasive fish species.
On the Animas River, illegal stocking hasn’t been too much of an issue over the years, White said.
One of the biggest concerns, however, is that smallmouth bass, which are stocked by private landowners in ponds along the Animas, will one day escape into the river, White said. The aggressive predatory fish is known for out-competing native species and taking over waterways.
And, White said that eventually, the invasive white sucker, which breeds with other species of suckers, pushing them out, will find its way to Southwest Colorado, like it has done in other parts of the West.
“It’s an issue that’s going to come forward at some point,” he said.
While illegal stocking hasn’t been a historical issue on the Animas, people have dumped non-native fish in other water bodies around La Plata County.
About 10 years ago, someone released goldfish into Chapman Lake, up Junction Creek Road.
“Now, there’s tons – huge schools of goldfish – swimming around up there, White said. “And they’re not the 4-inch gold fish you see at the county fair. They’re a pound, 12 inches long.”
More recently, Pastorius Reservoir, a few miles southeast of Durango, had to be drained in 2018 because someone illegally dumped northern pike, an invasive species considered highly dangerous to native fish, which raised concern it could escape and potentially reach the Animas River.
It was the third time wildlife officials found someone illegally stocked northern pike in the reservoir in 20 years, and the second time it had to be drained because of it. White said previously northern pike are generally considered fun to catch, which is why they are preferred among anglers.
White said people who illegally stock face fines up to $5,000, loss of hunting and fishing privileges, and seizure of the equipment used to do it, which can include cars or boats. Those responsible may even be on the hook for costs to fix the damage done.
But it’s notoriously difficult to capture culprits, White said. He said anyone with questions about what to do with their exotic fish can call CPW.
“This is not joking matter,” he said. “If people are confused with an exotic fish like that, they can always call our office and we can give them advice.