How's The Fishing? What Are The Trends? 17Jan22

I spent some time diving on data from electrofishing sampling done by CPW and their counterparts in Wyoming and Montana. I'm interested in whether the seeming increase in person-fishing-days from the pandemic has impacted fish populations. I also wonder if global warming, which seemingly is forcing lower flows and warmer waters, is impacting fishing in the Rockies. I couldn't get to my pandemic questions because recent data hasn't been posted or analyzed. I was able to understand some longer term trends though. First off, brown trout populations are declining across the Rockies! There may be some bigger fish but the younger populations especially are in decline. I have clearly personally seen this occur on the Arkansas (more later). The head of Montana's FPW Fisheries gave a talk to the Westslope TU chapter HERE and it's concerning.

I am most interested in Colorado conditions and trends and while there's little uniformity in data collection or reporting processes across our drainages, I could dive on information from some of the more popular spots. Before describing declines I should mention that the South Platte seems generally holding strong. It has many impoundments and therefore a lot of tailwaters. Here are snippets from home waters like Deckers, Cheeseman and the Dream Stream. They don't sample in 11 Mile Canyon but I fish it regularly and sense it is relatively similar to these results.

I should also say that the Colorado River, for much of it's length, is still very strong... gotta get there more. Strangely while all of Summit Co drains into the Colorado I don't fish it often due to its size. Also strangely, while I typically will hit the Williams Fk a half dozen times a year, I didn't even go at all in '21 ~ this due to the very low flows for much of the year.

Now for some not-so-good news. The freestone Arkansas fishery is in some decline. It is mainly a wild brown river and the biomass in the river has substantially declined over the past decade - especially below Coaldale. The Big Bend and headwaters sections seem to be holding a bit better. Overall the long term trend is a decline in brown trout.

Further downstream is another home water, the Pueblo Tailwater section. My personal feeling is that the fishing there is not nearly as good as it once was ~ and  the data somewhat bears that out. Note here that the Upper is the Valco Ponds/State Park area, Restricted is the Nature Center run, and that Lower is below the NC toward town. The data is mixed and tough here as population by size/length wasn't provided, nor was biomass, and the Upper is stocked every year. Browns aren't as prevalent in tailwaters, especially here,  so we can't observe that mega-trend.

Finally, the Blue River headwaters above Lake Dillon show a notable decline in brown trout population and biomass. It may be due to the significant building in the Breckenridge area but still... not good.

So, I'm generalizing but strictly as to fishing, our tailwaters are holding stronger as fisheries than our freestones. Unfortunately data from the Taylor River isn't available since 2016 and there's nothing new enough on the Gunny or Pan either but the old data already demonstrated some browns in decline on teh Gunnison. The exceptions might be Clear Ck and the Rio Grande, but again the data is a bit old - gotta get out to Creede and South Fork again this year. I don't know why but CPW has a lot more data on lakes than on our  rivers.