Its undeniable that there's a relationship between atmospheric conditions and fishing success. It's pretty reasonable to say that barometric pressure has a strangely large effect on fish behavior. It also seems reasonable to say that the how the pressure is changing seems more important than the current mercury reading. But beyond that, solid statements seem to get kind of murky.
Do different species of fish react differently to different barometric conditions?
Is it actually the pressure driving fish behavior or is it some other factor but pressure is also related (aka it's a correlation not causation)?
What else am I missing?
Good questions. I heard that an increasing barometer(higher air pressure) makes the oxygen concentration in the water go up, stimulating more activity in the O2 using critters.
But if you think about all the factors that might influence fish activity/distribution who knows what does what? Temp., Ph, salinity, photo-period, currents, etc., etc.
It's all about yesterday. You shoulda been there yesterday. :fish
Don't forget the moon phase! It certainly has an effect too. :fish
Biometric,,atmospheric,,,moon,,,cloud cover,,humidity,,temperature,,,,water temperature,,,,water levels rise or on the drop,,polushion,,,, ??? but knowbody knows how it going to effect your fishing for the day,,,,,, ;D
Well this weekend will be an interestkng one. Full moon, which in my experience doesn't bode well. And remarkably low pressure, which is also considered bad. But ill be by the water and i have no self control. So we'll see how it goes.
This was intended more for general discussion than about my weekend plans. But my weekend plans are what got me thinking about it.
Ooh, a sciencey question. Cannot resist-aaargh...
I am in the "nope" camp. Fish do respond to changes in weather, but changes barometric pressure is pretty much not detectable for a fish. It gets lost in the constant pressure change noise.
Significant barometric pressure changes are usually going to coincide with other weather related changes like cloud cover, wind (and therefore waves), rain, etc. It seems more plausible that these other environmental changes that do effect the predator/prey success equation,and therefore effect feeding behaviors, are the actual triggers.
Let's define what constitutes a significant change in barometric pressure. After looking at a couple weather sites, I am going to go with over 7mb (about 0.1 PSI) over several hours. That is about a 7/10s of a percent change in pressure at sea level. Pretty hard to be consciously detected by a land based animal, but maybe...
The difference for marine life is that water is much more dense than air and the amount of water above a fish is going to be constantly changing. A slight change in depth (like about 2 inches) will be the same as that 7mb change in air pressure. So as the depth changes from the fish moving up or down, or waves (even just ripples) passing above the fish, the pressure experienced is constantly changing, and a small change in the background over a long period of time will be impossible to detect without some fancy equipment, a spreadsheet, and a brain larger than a pea.
Even if there were significantly higher oxygen levels in seawater related to modest changes in pressure (which I am kinda skeptical on) - the above would still apply.
Quote from: MarkT on June 02, 2023, 06:06:03 PMDon't forget the moon phase! It certainly has an effect too. :fish
Don't get me started on moon phases :P
Quote from: nelz on June 02, 2023, 06:02:05 PMIt's all about yesterday. You shoulda been there yesterday. :fish
Can't argue with this. And even if the fishing is good today, well... today is just tomorrow's yesterday.
-J
Quote from: jurelometer on June 02, 2023, 11:55:12 PMQuote from: MarkT on June 02, 2023, 06:06:03 PMDon't forget the moon phase! It certainly has an effect too. :fish
Don't get me started on moon phases :P
I'm convinced moon phase does have an effect. If there's a bright moon in the sky at night, they can see snacks all night long so when your sketchy snack for them comes along they're not exactly starving enough to gamble on a maybe anymore. Real scientific i know
I always do awesome a few days before and after the full moon, especially targeting stripers and black drum, which I've currently been doing!
Been catching all kinds of flounder, on the boat as well and big ones too!
We even ran into some weakfish up here this week, that was nice to see them as well!
I am a firm believer on catching on the low pressure. It seems for me, especially with a storm coming in.
A slight change in depth is what you get with the tide change! That affects the current and without current the fish don't bite! No flow, no go!
sometimes I sits & thinks 'bout pressure... sometimes I just sits
either way, if I sits by the water with rod/reel, I feels better :fish
The only 1/2-way predictable fish behavior I know about are the anadromous salmonids. Certain months of the year and a good dose of rain and they enter the rivers. Wonder if the lunar phase affects that?
I know that the smolts will head back down towards the ocean and it seems to be; age, time of year(April best on the N.Coast)and Lunar Phase(new moon best, if I remember right).
I am a firm believer that if you're not on the water you're not going to catch any fish, regardless of the barometric pressure, moon phase or cloud cover. ;D :fish
Quote from: jurelometer on June 02, 2023, 11:55:12 PMOoh, a sciencey question. Cannot resist-aaargh...
I am in the "nope" camp. Fish do respond to changes in weather, but changes barometric pressure is pretty much not detectable for a fish. It gets lost in the constant pressure change noise.
Significant barometric pressure changes are usually going to coincide with other weather relate changes like cloud cover, wind (and therefore waves), rain, etc. It seems more plausible that these other environmental changes that do effect the predator/prey success equation,and therefore effect feeding behaviors, are the actual triggers.
Let's define what constitutes a significant change in barometric pressure. After looking at a couple weather sites, I am going to go with over 7mb (about 0.1 PSI) over several hours. That is about a 7/10s of a percent change in pressure at sea level. Pretty hard to be consciously detected by a land based animal, but maybe...
The difference for marine life is that water is much more dense than air and the amount of water above a fish is going to be constantly changing. A slight change in depth (like about 2 inches) will be the same as that 7mb change in air pressure. So as the depth changes from the fish moving up or down, or waves (even just ripples) passing above the fish, the pressure experienced is constantly changing, and a small change in the background over a long period of time will be impossible to detect without some fancy equipment, a spreadsheet, and a brain larger than a pea.
Even if there were significantly higher oxygen levels in seawater related to modest changes in pressure (which I am kinda skeptical on) - the above would still apply.
Quote from: MarkT on June 02, 2023, 06:06:03 PMDon't forget the moon phase! It certainly has an effect too. :fish
Don't get me started on moon phases :P
Quote from: nelz on June 02, 2023, 06:02:05 PMIt's all about yesterday. You shoulda been there yesterday. :fish
Can't argue with this. And even if the fishing is good today, well... today is just tomorrow's yesterday.
-J
Well, I'm no scientist by any means lol!
But I've read many many articles over the years that would have to disagree with your theory!
How can the fish not feel the pressure when the air is pushing down against water?
Especially if they're up in the shallows!
I remember one article distinctly, talking about something about their air bladder changing with the barometric pressure!
Guess it's time to hit the web again lol!
Quote from: Midway Tommy on June 03, 2023, 04:14:32 AMI am a firm believer that if you're not on the water you're not going to catch any fish, regardless of the barometric pressure, moon phase or cloud cover. ;D :fish
Exactly.
It took me a while, but I also decided that the best strategy is to go fishing when you can.
Quote from: ExcessiveAngler on June 03, 2023, 05:12:11 AMWell, I'm no scientist by any means lol!
But I've read many many articles over the years that would have to disagree with your theory!
How can the fish not feel the pressure when the air is pushing down against water?
Especially if they're up in the shallows!
I remember one article distinctly, talking about something about their air bladder changing with the barometric pressure!
Guess it's time to hit the web again lol!
There is plenty of BS out there in the fishing media when it comes to the science. I would suggest looking to the scientific literature. If you find something on the scientific side, I would be grateful to be corrected.
A swim bladder is an elastic sac filled with (mostly) oxygen. The volume of oxygen (and therefore the bladder) will expand and contract with the ambient pressure change. So the presence of a swim bladder doesn't affect the basic issue. The problem remains that barometric pressure changes are too small and slow to be significant amongst all the other much larger and more frequent pressure changes occurring.
Regarding depth: A 7mb change in surface pressure from a two inch ripple passing over in an instant, or a 7mb barometric pressure change over several hours will cause the same ambient pressure change (about 0.1 PSI) if the fish is at 1 foot or 1000 foot depth. The only difference is that the change as a percentage of the total ambient pressure will be different. So yes, a fish that is closer to the surface is more likely to notice a small change, but this still doesn't change the fundamental issue.
A bit more on swim bladders in most fish species: The fish will slowly adjust the amount of oxygen in its bladder to maintain relatively neutral buoyancy, but it is a somewhat slow mechanism, relying on changing the acidification levels in the blood to excrete, or absorb oxygen into or from tissue, including the bladder walls which is more oxygen permeable than other tissue. Or something like that :) . The purpose of of a swim bladder is to conserve energy by not having to swim up or down to maintain a desired depth. If you have done any scuba diving, you are already aware of the amount of energy required to maintain a specific depth if your buoyancy gets too far off kilter, but a little bit off doesn't matter so much. A swim bladder is very analogous to a diver's BCD.
Not a marine biologist myself, so any corrections from folk that are edjumacated in this stuff is appreciated.
-J
As an East coast South Floridian offshore fisherman, my buddies and I have a saying. Winds out of the West stay home and rest, winds out of the East prepare for a feast. Not sure why but when the ocean is at its nastiest the bite is alive
Quote from: thrasher on June 03, 2023, 12:39:04 PMAs an East coast South Floridian offshore fisherman, my buddies and I have a saying. Winds out of the West stay home and rest, winds out of the East prepare for a feast. Not sure why but when the ocean is at its nastiest the bite is alive
Interesting. I remembered seeing on the fishbrain website the lovely nursery rhyme "winds from the west fishing is best. Winds from the east fishing is least." And "winds from the south blow bait in fishes mouth. Winds from the north do not go.forth."
But that's clearly not universal.
Funny, I was talking with a bass fisherman once and he quoted the same thing as you. I know you're on the West coast so it's probably opposite but a West wind here makes the ocean flat as a lake. Good for a boat ride but you really have to work to find the fish. Just a local point of view and like you said, not universal.
Also had a discussion with that bass guy about atmospheric pressure. Something about relaxing the pressure on the swim bladder which releases pressure on the stomach which makes the fish hungrier than normal. Sounds good in theory but who knows, the bite does seem to be good before a storm rolls through.
I'm convinced that there's a lot of bad advice out there that continues to circulate only because it rhymes.
"Beer before liquor never been sicker, liquor before beer youre in the clear"
If youre already quite buzzed on the slow stuff and you start on the fast stuff you'll probably have a bad time. But i had friends growing up who were convinced that it guaranteed if they had a beer earlier in the day they couldn't ever drink a mixed drink at night or they'd yak.
"He who smell't it..."
The best way to identify trends is to keep a diary/log with all the pertinent information documented, barometric pressure, temp, wind direction, cloudiness, humidity, etc. After a decade or two of documentation you will be able see trends and calculate success based on that information. I know a few guys that do it and it actually works, but I'm too lazy to invest the time and effort it takes to be thorough with it so I just add the info to my hippocampus for later use. ;) Problem is, the older I get the more that area is getting overloaded so sometimes the info is a little tough to sort out. ;D
I do know that in freshwater fishing, fishing is generally pretty darn good when you have an extended fair weather period and also good just prior to a front coming through and the day after, but pretty darn bad for about four days after the front passes. Also, on average, some type of front passes through about every five days or so, so the trick is to figure out how to catch fish on those less desirable fishing days. ;)
Does not matter what I look at and try to trend it out, fish seems to bite 2x a day,
Before I get there and
After I leave!
what, no one sprinkled in a little thermocline, yet? :o
just for poops & giggles, let's make it wind-blown... "diagonal" rather than horizontál
For kokanee light penitration is more of a factor. On clear days they tend to go deeper,
often below the thermocline and into colder water. The fishes metabolism slows down and they become sluggish and not as prone to bite. I also THINK light penitration has more effect than pressure for most fise and I KNOW rapid temperature changes do.
As for pressure a few inches vertical movement changes pressure far more than even the worse front and I realy can not see it efecting fish that much.
Moon phases.... I think it is feeding related, if they are feeding at night they are not going to be eating as much during the day. This is just a guess though.
Quote from: thrasher on June 03, 2023, 12:39:04 PMAs an East coast South Floridian offshore fisherman, my buddies and I have a saying. Winds out of the West stay home and rest, winds out of the East prepare for a feast. Not sure why but when the ocean is at its nastiest the bite is alive
Larger fish can swim more easily in moving water that pushes smaller fish around. A feeding opportunity if there ever was one.
I believe it has something to do with how water molecules attract each other. Some microscopic critters actually crawl through water, because for them, it is like a sludge. For a whale, the opposite. [correction- while the previous is correct, the main benefit in this situation comes from simply being larger- fish can cover some multiple of their body length per muscle contraction/tail swipe- the bigger the fish the longer the distance, and therefore a big fish can move faster than a small fish, countering the effects of current]
QuoteAlso had a discussion with that bass guy about atmospheric pressure. Something about relaxing the pressure on the swim bladder which releases pressure on the stomach which makes the fish hungrier than normal. Sounds good in theory but who knows, the bite does seem to be good before a storm rolls through.
Not buying this one. First of all when the atmospheric pressure drops ahead of the storm, the swim bladder would be at a relatively higher pressure and would therefore expand. Secondly, the fish is slowly and continuously adjusting the amount of oxygen in the swim bladder, and the atmospheric pressure change is happening at a relatively slow rate.
Thirdly, if the fish move a couple inches higher or lower in depth, the swim bladder would immediately grow or shrink (at least for awhile until readjusted) the same amount as would be caused by barometric changes from a weather event. So fish would be constantly be going between being hungry and full as it swam around and/or small waves passed overhead. Not possible to survive like that. We covered the swim bladder thing in more detail earlier in this thread.
It is common to mistake correlation for causation. On the saltwater flats, fish will often eat better when the wind whips up a bit, and also when it gets overcast. Trout in streams will go on the bite when it gets overcast, and especially at the beginning of some rain (which dumps flying insects onto the water). These events often correspond with a drop in barometric pressure, but that doesn't mean that the pressure change was the actual cause.
Another story: the most insane wide open multi-species bite that I have ever witnessed was the first couple of calm days after a small hurricane passed through the Sea of Cortez. My guess is that the bite wasn't the result of barometer rising, but the fact that it was too rough for the inshore fish to feed for a couple days, and they were hungry.
-J
Hmmm, so when a fish ralfs-up its gut contents on the way up from deep water, it might be the swim bladder quickly expanding to push out the stomach stuff.
Then again a "shock trauma" reaction in people, after an accident is to vomit-up the stomach contents...
Quote from: Gfish on June 03, 2023, 05:27:30 PMHmmm, so when a fish ralfs-up its gut contents on the way up from deep water, it might be the swim bladder quickly expanding to push out the stomach stuff.
:ct
Yes
Fish definitely respond to a falling barometric pressure. Part of my job used to be keeping red drum broodstock in large indoor tanks with temperature regulation and an artificial light cycle. They would gradually be bought through artificial "seasons" by manipulating the light and temperature regime. When the artificial season reached fall conditions fish would be full of eggs and ready to spawn. However, the actual spawning event would not occur until there was a falling barometer; something we could not control artificially.
A falling barometer is an indication that a storm is coming. All animals react to it. Deer feed earlier in the day and longer so they can hunker-down and wait out the storm. Elementary school teachers say that their class will be especially unruly on days that the barometer is falling. It is always a good time to go fishing because the bite will be on.
In Hurricane Alley you should always prepare for a storm early so you are free to go fishing when the barometer starts to fall.
This was fun. Barometer very low today
Quote from: oc1 on June 03, 2023, 06:56:18 PMFish definitely respond to a falling barometric pressure. Part of my job used to be keeping red drum broodstock in large indoor tanks with temperature regulation and an artificial light cycle. They would gradually be bought through artificial "seasons" by manipulating the light and temperature regime. When the artificial season reached fall conditions fish would be full of eggs and ready to spawn. However, the actual spawning event would not occur until there was a falling barometer; something we could not control artificially.
A falling barometer is an indication that a storm is coming. All animals react to it. Deer feed earlier in the day and longer so they can hunker-down and wait out the storm. Elementary school teachers say that their class will be especially unruly on days that the barometer is falling. It is always a good time to go fishing because the bite will be on.
In Hurricane Alley you should always prepare for a storm early so you are free to go fishing when the barometer starts to fall.
Sorry, still not buying it. You have some coincidental data, and no causal mechanism. It does not make sense that a species would not spawn until a weather event happened that could take weeks or even months in extreme cases.
Here is one reference from a scientific paper (published in Fish and Fisheries) on what makes a fish vulnerable to capture by hook - https://www.fecpl.ca/wp-content/uploads/2017/02/Lennox-et-al.-2017-FishFish.pdf (https://www.fecpl.ca/wp-content/uploads/2017/02/Lennox-et-al.-2017-FishFish.pdf):
It is often suggested that fish can sense changes in barometric pressure and modify behaviour accordingly (Guy, Neumann, & Willis, 1992; Heupel, Simpfendorfer, & Hueter, 2003;| 7LENNOX Et aL. Jeffrey & Edds, 1999; Mallekh, Lagardere, Anras, & Lafaye, 1998). There is, however, a lack of consensus on this (e.g., Anras, 1995; Schulz & Berg, 1992) and the only direct test of barometric pressure changes on fish vulnerability found no relationship in northern pike (Kuparinen et al., 2010).
Changes in barometric pressure are small and slow relative to the changes in hydrostatic pressure experienced by fish during even small vertical movements.
For example, the pressure difference from swimming upward ~10 cm in the water column is equal to the change in barometric pressure from a typical high to low pressure system (Ikegami et al., 2015; Northcott, Gibson, & Morgan, 1991).
Responses to barometric pressure are reactions to other weather changes or possibly to other weather changes correlated with changes in barometric in a predictable way (Cabanellas-Reboredo et al., 2014; e.g., infrasound)Same point that I was making - there is too much continuous pressure change going on in the fishes natural environment to make detection of a very small change over a long period of time plausible. Nevertheless, there are hundreds of sportfishing articles that treat this claim as some sort of proven fact.
On land, the situation is different due to the much lighter density of air. Very little air pressure variability assuming that you are not drastically changing elevation (like hundreds of feet at least), or sticking you head out of a speeding car window for hours. Barometric pressure change could be detected, and therefore acted on.
Quote from: JasonGotaProblem on June 03, 2023, 07:04:27 PMThis was fun. Barometer very low today
Nice!
Success was most likely due to your lucky hat, lucky socks, or both.
-J
the fish don't have a barometer... neither do I... SPORTSMANSHIP!!! :D
Ok I fish any day,,,,, ;) but there's different ones,,,, >:( bad one's is the air temperature drops and the worst thing is polushion coming down the river or in Florida it's red sea,,,,, ;D
I think that the observation of atmospheric pressure changes in relation to redfish spawning in captivity that Steve mentioned was probably a red herring. I did a bit of reading on redfish aquaculture. It looks to me like they do it with just light and temperature. No air pressure changes needed. Here is a good quick overview from the UN Food and Agriculture Organization:
Techniques for year-round spawning are well established for this species. A 120 day photoperiod and temperature regime can be used for spawning red drum in captivity. Broodstock are initially acclimated to a temperature of 17 °C and a photoperiod of 9 hours light (HL) which simulates winter conditions for naturally occurring adults. Following the acclimation of the adults, temperature and photoperiod are gradually increased and subsequently decreased over a period of 120 days.
Following initial conditioning of the broodstock, controlled spawning may be achieved throughout the year by manipulations in temperature. For example, spawning may be temporarily suspended when the water temperature drops below 23 °C and resumed once the temperature is raised beyond 23 °C. Red drum usually spawn just after the lights turn off in the evening.
Source: https://www.fao.org/fishery/docs/DOCUMENT/aquaculture/CulturedSpecies/file/en/en_reddrum.htm (https://www.fao.org/fishery/docs/DOCUMENT/aquaculture/CulturedSpecies/file/en/en_reddrum.htm)
I am still a hard nope on atmospheric pressure change alone having a direct effect on fish behavior, but am softening up quite a bit the full moon thing. Had the time to do a bit of reading, and the subject turned out to be much more nuanced than I anticipated. But as to be expected, the stuff in the fishing press on this topic is mostly nonsense.
-J
Re: full moon. Snook only spawn during outgoing tide on a full moon. The females will go to inlets and orient themselves facing inland tail pointed out to sea. The males then headbutt them in the belly to make eggs squirt out so they can try to fertilize them on their way out to sea.
Super romantic. But that's why they go out of season over the summer. Their behavior is so predictable that it's just too easy.
Full moon this weekend. Unsurprisingly fishing far from any inlet there wasn't a single big snook to be found. Forgive me for being so Florida-centric in my fish stories.
Quote from: JasonGotaProblem on June 05, 2023, 01:55:10 AMSuper romantic. But that's why they go out of season over the summer. Their behavior is so predictable that it's just too easy.
Very similar to Grunion here on the Left Coast. Grunion runs (spawning) are very predictable with high tide and full moon, and during a certain time of year they are a closed season. Other times of the year you are allowed to take but the only equipment allowed is your own two hands. - john
Quote from: Brewcrafter on June 05, 2023, 02:06:18 AMQuote from: JasonGotaProblem on June 05, 2023, 01:55:10 AMSuper romantic. But that's why they go out of season over the summer. Their behavior is so predictable that it's just too easy.
Very similar to Grunion here on the Left Coast. Grunion runs (spawning) are very predictable with high tide and full moon, and during a certain time of year they are a closed season. Other times of the year you are allowed to take but the only equipment allowed is your own two hands. - john
Down in Baja the spring there are these giant aggregations by species of groupers,jacks, snappers, etc. Starts right around a week or two before the full moon. The actual spawning sites are closed (year round) in a few locations, which is mostly a good thing if you ask me.
About a month ago, I was fishing the shallows and couldn't buy a bite for hours. Figured there wasn't a fish in the area. Then all of a sudden a tight school of humongous dog snapper started milling around on the surface nearby. Less than a minute later a tight school of big amberjack ambled by, right under the boat. I could get fish from both schools to sniff at the fly, but that was it. They were slightly more interested in the unhooked live bait we tossed out, and ate a couple.
Probably just as well. I had a chance with the amberjack, but if one of those dog snapper took the fly, I would have been sawed off over a rock in about 0.5 seconds.
It was around a week before the full moon. If I stayed home because of the moon phase, I would have missed the experience, which was pretty cool and didn't require catching any fish.
It would be fun to see the snook and grunion spawning.
We should start another thread on the full moon thing.
-J
Lunar phase, photo period, I'll toss in water temp. too. Maybe all these are species oriented and possibly also a regional thing.
Water pressure doubles every 33', a major change in air pressure is not noticeable underwater.
Light penitration has more effect than air pressure. Fish can not close their eyes so they go deeper when it is bright.
Quote from: Keta on June 05, 2023, 03:55:01 AMWater pressure doubles every 33', a major change in air pressure is not noticeable underwater.
Yeah, and a drop in barometric pressure ain't major. I don't know how many times we need to repeat this before it sinks in :) An incoming storm changes the pressure on the the fish the same amount as a vertical move of two inches or so, or a little ripple on the surface of the water.
QuoteLight penitration has more effect than air pressure.
Fish can not close their eyes so they go deeper when it is bright.
And almost all fish can't dilate the pupil to control light intake level like us humans do (sharks are the exception). Some species can adjust the rod/cone layout in the eyes for night vision, but it takes hours, and is based on time of day and not currently available light.
Lots of environmental factors can effect fish behavior, but I am not sure it will all fit in one thread.
I'm going to start another thread on the full moon thing.
-J