What did the fish say when it ran into the concrete wall?
Dam.
I will let that sink in for a minute for some of you. For the rest, let me talk about fish barriers. You know, things like dams.
There are thousands of barriers to fish movements on Nebraska rivers and streams. Some of those barriers are natural, waterfalls or chutes. Most are man-made and include a variety of major dams and smaller diversion structures. Some are as small as culverts, drop structures.
You might think those barriers are not a big deal, especially on some of the smaller creeks and streams. Just know that there are barriers on Nebraska rivers that prevent migrations of species like channel catfish. Those barriers reduce additional sport fishing opportunities.
Smaller streams can be important spawning and nursery habitat for larger species or for the prey fish that feed those larger species. No doubt there are a lot of barriers that prevent a variety of fish, large and small, from completing their life cycle and thriving. Even if those fish are small and never caught by anglers, they are still important components of Nebraska’s aquatic ecosystems.
So, barriers on Nebraska rivers and streams are a big deal and you should be concerned about them, even the smallest of them. In the Pacific Northwest folks know about fish “ladders” or passageways where those structures are important for salmon runs. But, did you know that similar fish “ladders” have been installed on Nebraska rivers (Fish Passageways in Nebraska?)?
Similar, but smaller fish ladders are being installed on some Nebraska streams. If you wish to purchase a subscription to the Ainsworth Star-Journal, you can read a recent article, NGPC Tests Detachable Fish Ladders on Cub Creek and Other Niobrara River Tributary Drop Culverts.
I cannot copy and paste that article here, but I can show you some photos of the structures:
Part of what you are seeing on those structures is a trap on the upper end. To evaluate how well the fish ladder works, the trap captures fish that have successfully used the ladder. I do not have any data to share, it is too soon for that, but the article mentioned there were fish in the traps.
Notice that fisheries biologists sometimes have to get into their work! Joe Spooner supplied the photos. Thank you, Joe. Thanks for getting wet!
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