Colorado wildlife officials have confirmed the fish population in the Animas River has been severely depleted by flooding and debris flows from the 416 Fire burn scar.

The 416 Fire in 2018 scorched an estimated 54,000 acres of mostly U.S. Forest Service land in the Hermosa Creek watershed, historically one of the Animas River’s cleanest tributaries.

After the fire, heavy rains hit the burn scar in July and September 2018, bringing down runoff filled with ash that suffocated fish.

Wildlife officials suspected significant losses of fish in the Animas, and a small survey last year wasn’t encouraging. Last week, Colorado Parks and Wildlife conducted its first full-scale survey since the flooding, giving a better picture of the situation.

In 1996, a 4-mile stretch of the Animas River from the confluence of Lightner Creek down to the Purple Cliffs, by Home Depot, was designated a Gold Medal fishery, a label that highlights Colorado rivers and creeks that provide outstanding fishing opportunities.

To qualify, a waterway must meet two criteria: a minimum of 60 pounds of trout per acre and at least 12 trout measuring 14 inches or longer per acre.

The survey last week, however, showed the fishery didn’t come anywhere close, said Jim White, an aquatic biologist with CPW.

Researchers found just 28 pounds of trout per acre, a 64% decline from the Animas River’s historical average of 78 pounds per acre.

And, only one 14-inch fish was found per acre – a 95% decline from the river’s historical average of 22 per acre.

White said that among all fish species in the Animas, populations are down about 80% because of 416 Fire flooding.

“When I crunched all the numbers, that was the take-home,” he said. “And it’s not surprising.”

But, there is some good news to report, White said.

Heavy snowpack this winter led to high and sustained runoff this spring and summer. The runoff cleaned the river bottom, home to many fish and the insects they like to eat.

Native bluehead suckers were caught in record numbers. In 2016, for instance, 37 suckers were captured. This year, more than 160 bluehead suckers of various ages were caught. White speculated that because suckers travel long distances, they likely escaped the 416 Fire runoff and have returned.

Ty Churchwell with Trout Unlimited said despite the fish die-off, anglers are catching quality fish in the Animas.

“While the Animas definitely suffered as a result of the ash flows from last year’s fire, local anglers are reporting they are catching fish, and that’s encouraging,” he said.

For various reasons, trout are unable to reproduce naturally in the Animas, so fish populations rely on regular stocking by CPW. Churchwell said Trout Unlimited supports those efforts.

“While it was a horrible setback, we’re on the road to recovery,” he said.

Trever Garfield, a retail associate with Duranglers Flies and Supplies, said the guiding company and other businesses took a hit because of the die-off.

“Not having that as a fishery in our backyard impacts a lot of businesses in town,” he said.

But when the Animas is out of commission, Garfield said there are plenty of other fishing opportunities in Southwest Colorado.

“We’re used to shuffling things around,” he said.

White said that since the flooding, CPW has stocked about 6,000 10-inch rainbow trout. He said CPW would continue to monitor and stock fish in the Animas, which could return to Gold Medal status in two to three years.

“I think it’s worth mentioning the Animas River is not in threat of losing the Gold Medal status just because we don’t meet the standards for a couple years,” he said. “If it was looking more like 10 to 15 years, then it would be more of a discussion to pull the status.”

jromeo@durangoherald.com