In a state known for its trout, biologists break down four of the most fish-rich rivers | Regional news
Wyoming measures Blue Ribbon fisheries by those holding more than 600 pounds of fish per mile. It is the highest honor a stream can receive in the state, achieved by only about 15 rivers.
But the Gray Reef section of the North Platte River raises the 600-pound mark. In 2020, he had 3,300 pounds of trout per mile, or about 1,900 actual trout.
You read that right: over 3,000 pounds of fish.
Biologists attribute much of the abundance of trout to the habitat and hunting streams of the Bureau of Reclamation. It is also leakage water, which means that water flows from a dam to the bottom of a reservoir. Tail waters are generally more productive because temperatures stay cooler in summer and warmer in winter, which helps trout growth.
And fishermen take advantage of the teeming populations of brown and rainbow trout. In 2009, the most recent data available, over 18,000 anglers fished between Gray Reef and Robertson Road. That equates to over 85,000 hours of fishing, and it’s probably a little higher today.
While Gray Reef has plenty of fish, it’s actually not the stickiest waterway in the state right now. The Shoshone River near Cody wins this award, although Gray Reef may reclaim the top spot one day.
“Populations are not static,” said Mark Smith, assistant fisheries management coordinator for Wyoming Game and Fish. “These numbers are constantly changing.”
State fishing experts have broken down three other major state rivers of equality in terms of fish counts and pounds for the Star-Tribune. And don’t worry. If your favorite river didn’t make the cut this time, it might be there in the future.
Middle Fork of the Powder River, South of Big Horns
This iconic section of water near Kaycee tumbles through a rocky canyon and is home to more than 4,500 trout per mile, or about 3,200 pounds, Smith said. Rainbow and brown trout average between 11.5 and 12 inches long. Its advantage? Not many people are willing to take the long back roads and descend the steep canyon trail to reach the river, which limits the competition.
Upper North Platte River, Saratoga
The upper end of the Gray Reef section may not have quite the same number of fish as the bottom, but it is still one of the upper streams. Fisheries biologists have recorded roughly 2,000 fish per mile in the Treasure Island area of the upper North Platte River near Saratoga. In pounds, that comes down to around 1,300, Smith said. And that’s just wild trout. The river has not been seeded since the mid-1980s.
Average sizes are around 10 inches for rainbow trout and brown trout, with the larger fish measuring up to around 23 inches.
Shoshone River, Cody
The Shoshone River near the Buffalo Bill Reservoir has always been a good catch, but right now it could be at the peak of its productivity, Smith said.
About 4,800 trout swim in the river per mile, which equates to about 4,500 pounds of fish. The medium brown trout is just over 11.5 inches tall and the largest rainbow is over 13.5 inches. Some of the larger trout are over 21 inches long.
Smith credits the nature of the river’s leakage water, which keeps the water at a constant temperature year-round, as well as a large hot spring under the dam that helps keep the cold at bay in the winter.
The river has seen years of flooding and heavy snowfall, which has further helped the trout populations.
“We’ve really built a fish population that’s probably near an all-time high,” he said. “And that probably won’t last very long.”