Barometric pressure and fish suspension

[tennfisher]

There is an article in the latest issue of a highly respected fishing magazine that addresses fall crappie fishing and the impact of barometric pressure on the tendency for crappie to suspend or to hug the bottom. The author takes the position that when the barometer is rising or there is high sustained pressure, the crappie or more likely to suspend; and when the barometer is low or falling the fish are more likely to hug the bottom. Now I will leave it to you folks who are far better fishermen than myself to agree or disagree with this perspective. What has me puzzled is the author's explanation for this behavior. He states "low pressure allows a crappie's air bladder to expand, while high pressure causes it to contract. When their bladder expands, crappie can move deeper."

This just seems to me to defy the laws of physics. It would seem to me that an expanded air bladder would increase buoyancy, making it more difficult for a fish to go deep; and a contracted air bladder would result in less buoyancy and thus make it easier to a fish to achieve depth. Haven't I read lots of threads over the years on the problem of pulling bass from deep water and having to take steps to deflate their air bladders to enable them to get back to the depths if released? Am I missing something here or does this article have a problem? emoScratch

Tennfisher

 

[SlabDog]

I agree with you, if true, it would be backasswards in my book. A quick search and a bit of reading confirmed this. Also, the fish adjusts the swim bladder volume of gas to suit it's needs and not barometric pressure which makes sense. If not, then all fish with a swim bladder would be dependent on the barometric pressure to be shallow or deep and we all know that that is not so. Bass, crappie etc...can be deep and shallow at the same time on the same day whether high pressure or low pressure is present. IMO anyway.