Barometer vs Kokanee?

[Lou Smith]

I read some east coast commercial fishermen’s posts about their observations to changing barometric pressure and their fishing success. Fish with large air bladders are most affected by barometric pressure changes (trout, redfish, tarpon, grouper, snapper,…). Of our local Puget Sound area fish (sockeye, king, steelhead,…) the Kokanee has the largest proportional air bladder which runs the whole length of the body cavity and makes it recognizable on color fishfinders. Therefore, the Kokanee should be the most sensitive to barometric changes.

When the barometer is high, the fishing is usually good. When a cold front approaches (lower barometric pressure ahead of the front) fish sense this and feed heavily to wait out the low pressure at depth. With less pressure on the air bladder (lower barometric pressure) the bladder expands and is uncomfortable for the fish with the larger air bladders. So, they go deeper (more pressure on their bladder) and wait.

After the low front passes, these fish may not feed aggressively for 24 hours. The fishermen observed that 1 to 2 days after the high pressure moves back in, the fish stabilize and an intense bite occurred. The fishermen were basing their fishing times to the barometer with higher success and a savings in fuel.

Personally, I have adjusted by fishing habits based on the timing of pressure cells (The Weather Channel) coming into western Washington with a higher degree of success. But, we are dealing with the unpredictable, finicky Kokanee. Other times it is cabin fever (no fishing for a week) that forces me out there, regardless.

[G-Man]

I've found that this is true not only with kokanee, it applies to trout found in lakes as well. The trick is finding a reliable source for a pressure reading near the body of water you are targeting. I've found that there are a number of public schools that post their weather information on line which comes in handy when fishing outside the metro areas.

[The Quadfather]

G-man,

I curious about the reading of the barametric pressure. Within my job I have to take the barametric pressure daily. You said something about being "Close" to the lake in question. If my work place is in N. Seattle near the big Washeli cemetary on Aurora, would that be close enough to Lake WA. to have a bearing on fishing conditions in the big lake?

Typicaly my readings are numbers like 1.0103 ( I think at least, I wasn't the person to record it the past few days)
Is this approx. the type of number that you are seeing in the Seattle area? Or it could be that our barametric pressure reading equipment uses some kind of fudge factor in it's readout. I am expecting that is close to the raw number.

edit: I could make more use of reading the number the day I intend to go out.

[Amx]

Also depends on whether it's rising or falling, not just holding steady.

[G-Man]

Quad, you can check your readings against the weather buoy found on Lake Washington. I think what you'll find in most cases is that they will be very similar. As AMX mentioned, you want to see if it is rising or falling over a period of time. If you have a handheld GPS unit, many of them will display the barometric pressure and can put up a graph for you as well. In the greater Seattle area, the pressure changes will typically be similar throughout the region. However, it is possible that a front could move through the area, effecting one section while leaving the others alone, so it is always best to check close to where you want to fish. Typical barometric pressure in this area is between 990 to 1040 and a slight change is nothing to be concerned over.

[Bodofish]

I concur whole heartedly on the barometric issue with fish. I've witnessed it far too many time to not make the correlation. Quad, as far as the pressure goes, for fishing, I don't think trying to manage and guess micro cells is going to be of any benefit. If you have good steady high pressure at work the lake should be fine!!! This is my go to for weather, it's very rarely off. All I suggest is if you use please donate, funds are shy and there are no ads. http://www.atmos.washington.edu/data/ Take your time, it won't hand it to you on a platter, but all the data the big boys use is at your disposal.

[BentRod]

Scads of information on this topic if you do a Google Search on "barometric pressure fishing". Lots of articles, tips, charts, etc.
You can buy fishing barometers like this one:
But, if you have a hand held GPS, you might already have a portable barometer. Many use barometric pressure to determine elevation gain and can be set to show barometric pressure instead of elevation....at least both my Garmin units do.
I tried using this feature a few years ago to see how barometric pressure effected the bass and trout bite on Beaver and Pine lake. I couldn't get any consistent results that jived with what I'd read, so finally gave up. If you do a search on the WL forum, you'll also find previous discussions on the topic. My conclusion is that it most likely does have an effect, but there are other factors involved and the size/species of fish may play a role in how much of an effect barometric pressure has on feeding.
FWIW,

[Bodofish]

I haven't found much correlation for planters but I think it takes a while for them to learn to dive deep or get sensitized to the pressure changes. They spend at least the first part of their lives in a 4' deep pond. Go over to Rufus and you will see a very pronounced effect. Fish that live in deep water I think are more sensitive to it.