Too Hot for Trout

[rrt]

I just read an article by Mark Nale in "Pennsylvania Outdoor News" where he cited an article from the Keep/Fish/Wet website called "Fishing for Trout in Warming Water," written by Jamie Madden. From her research for her Masters Degree, she examined many articles and came up with the following:
1. Brook, rainbow, and other trout's "angling threshold" is about 61 degrees.
2. Brown trout's angling threshold is 66 degrees.

These two figures are lower than the commonly publicized temperature of 68 degrees that we have long believed to be the cutoff for when we should stop fishing for trout.

I googled up the article and read it.

Madden writes that "the concept of an angling threshold--a temperature at which mortality begins to increase exponentially (usually going above 5-10% just from temperature) and at which anglers need to start being exceedingly aware of every interaction they have with fish. Some anglers may also decide that this is when they want to stop fishing."

I do not get to fish much for brook trout during the summer, but I do have occasion to fish for some rainbows, with most of my fishing adventures being for brown trout. I have long used the 68-degree temperature as my cutoff, though, luckily, I often am able to fish in cooler water.

Anyhow, if you want to do a little reading, look for Nale's article in PON, or google up the Madden article. Reading these will make you think about what is appropriate for summer trout fishing.

 

[wildtrout2]

I fished a Sullivan county stream yesterday that was at 56F. There are plenty of mountain freestone streams that never get "too hot for trout", if you know their locations and are willing to drive.

 

[Wild_Trouter]

I fished a Sullivan county stream yesterday that was at 56F. There are plenty of mountain freestone streams that never get "too hot for trout", if you know their locations and are willing to drive.

^Don't forget hiking. For the places I fish, I have to go up in elevation to find what I seek. Totally worth it imo.

 

[wildtrout2]

^Don't forget hiking. For the places I fish, I have to go up in elevation to find what I seek. Totally worth it imo.

You're right. Often, these streams require X amount of hiking to accesss them, and to fish them, for that matter.

 

[Tigereye]

61F. ?????

That's a bit on the cool side. Was always under the impression that DO dissolved oxygen concentration was the limiting factor and above 68F the DO was diminished enough that it could be harmful to overplay trout.

If I had the time, curiosity, and inclination to do so I would research her study. But alas, it would mater little as I will continue to use 68 as a go- no go metric. Fishing season is short enough. She wants to basically eliminate may through october.

 

[krayfish2]

I was thinking of the study they did on the Delaware quite a few years back. Radio tags indicated that rainbows were on the move at 62°. Those fish are known for being very mobile throughout the system and tolerant of warm temperatures but 62 was the mark that really put them on the move. Someone up river, some went down, some went to feeders or spring holes

 

[wildtrout2]

61F. ?????

That's a bit on the cool side.

Yes it is. I'd kill to get water temps of 61F! Some of my very best days, numbers wise, were when the stream temps were at 60F-61F. The streams I'm referring to are almost always in the mid to high 50's when I fish them in the summer.

 

[rrt]

One other thing with this: I think it was in Len Wright's "The Ways of Trout" where it was explained that a trout's ideal metabolic water temperature was about 63 - 64 degrees and that the faster and closer the temp approached the ideal, the more active the trout were. I have found that true for dry-fly fishing.

However, with the Madden study, that would appear to be a threat to brook and rainbow trout.

I hope further studies contradict Madden's. I guess I am lucky I fish mostly for brown trout where the temps are usually 66 or below when I fish for them. (I was pretty much absent from trout fishing for about 6 weeks during the real hot weather we had this summer, mainly due to what I thought the water temp would do to the trout and what the air temp would do to me.)

Anyhow, this study is pretty thought-provoking.

 

[greenghost]

61 ??? That's flat wrong. Someone who knows the correct way to structure and perform a study like this needs to scrutinize the details of that study. I bet they find errors.