Warm water and effects on river trout

[JACKspASS]

Perspective: Trout fishing during low water and high temperatures

Summer of 2024 is shaping up to be one of the hottest on record, so we are reposting this article from 2022 because it relevant to what many anglers are experiencing this year. This research was completed several years ago, but the conclusions are still applicable today. Higher stream...

idfg.idaho.gov

Interesting read, I don't fish for trout much in summer with exception of alpine lakes and little headwaters streams, thought some of you might find this interesting

 

[Canuck from Kansas]

Perspective: Trout fishing during low water and high temperatures

Summer of 2024 is shaping up to be one of the hottest on record, so we are reposting this article from 2022 because it relevant to what many anglers are experiencing this year. This research was completed several years ago, but the conclusions are still applicable today. Higher stream...

idfg.idaho.gov

Interesting read, I don't fish for trout much in summer with exception of alpine lakes and little headwaters streams, thought some of you might find this interesting

"but a recent study on Idaho rivers during a hot summer showed catch-and-release angling did not harm the trout population."

While technically correct since the low catch rate (77% lower) compensated for the increased mortality (69% higher), this really doesn't address the ethics of fishing in warm water, knowing that the fish you catch will have a much lower survival rate. It's not just about the numbers.

cheers

 

[Old406Kid]

I'm not a biologist but I still think that Hoot Owl restrictions are a good thing and not really that big of a sacrifice.
The local bars just need to get on board and start "Happy Hour" at 2:00.

 

[tkww]

DFW's are quite reticent to remove "opportunities," so it's no surprise that they found a way to statistically justify a radically higher mortality rate.

 

[Matt B]

"In the Big Wood River, the normal yearly mortality of trout is between 50-70%!"
^^ I found this surprisingly high. I wonder how it compares to other rivers across the West. I also wonder if in a higher pressure, multi-year situation, like say many Montana rivers, if the conclusion might be different.
It was a good read; thanks for sharing.

 

[Mike Cline]

"In the Big Wood River, the normal yearly mortality of trout is between 50-70%!"
^^ I found this surprisingly high. I wonder how it compares to other rivers across the West. I also wonder if in a higher pressure, multi-year situation, like say many Montana rivers, if the conclusion might be different.
It was a good read; thanks for sharing.

I suspect that 50-70% number includes 1st year fry and not just yearling and older adult fish. Every time I’ve listened to a MT FWP fisheries manager talk about mortality, the number is usually 20-30% turnover every season. In other words, 1 out of 5 or 1 out of 4 adults in the river is going to perish every season due to predation, disease, starvation, post-spawn stress or injury. Stress from angling is no doubt a factor to a point, but minor when compared to all the other bad things that can happen to fish in a river. Healthy watersheds with good annual recruitment that keeps trout numbers at or near the carrying capacity of the stream is far more important than trying to eliminate angler induced stress.

In a local trout stream, currently under hoot owl restrictions, the volume of fry (minute to 2 inches) in the shallows is phenomenal. Literally thousands of brown and rainbow trout and whitefish fry can be found in shallow, placid sections of the stream. If they all made it to yearling status, you could walk across the backs of fish in the river. The brown trout spawn in September and October in this stream along with whitefish. The rainbows spawn early when the river is essentially too cold and un fishable in the late winter. There is no shortage of progeny. It is insect rich and I suspect it is near its carrying capacity for adult trout. Somehow they seem to survive our hot, dry MT summers as well as the anglers who target them.``

 

[Old Man]

The local trout in the Butte area have nothing to fear from me. I haven't touched a fish in two years now. Bought a license but the heat has kept me home. Not going out in the 90's anymore. Besides my god damn truck seems to go into lock up mode when it's hot out and I'm driving slow.