Replying To Questions On Barometric Pressure & Fishing....

[jewgaffer]

G'day Jewgaffer,

is there a scientific explanation behind the connection between barometric changes and fish feeding? Or is it more an association? I'm keen to find out if you base your info on speaking to lots of other fishos and your own experiences or is it from other sources scientific or other in nature?

......I've heard the swim bladder theory, where the higher the barometric pressure = external pressure on the fish's bladder (presuming that the barometric pressure has enough of an effect to transfer into the water and to thus to the fish) and thus more room for the stomach to expand in the abdominal cavity triggering a feeding response by telling the fish it needs to be filled!

........I'd be keen to find out if there are actual explanations for these associations that people talk about with barometrics or are they gained from the combined experiences of thousands of fishos over many hundreds of years!

Cheers.

Hi Everyone and to Klainz and the twins Marcel/Twin1 & Ray/Lumpookey...... I decided to make my reply to your questions and concerns a new topic so that other members can assist with their input and provide their own opinions based on their experiences with barometric pressure readings and fluctuations and their own fishing results, to hopefully add more to this subject for the benefit of others.......

I don't know much about scientific explanations or findings in regard to the good and the bad times to fish, but I will answer the science question by saying first of all, and for others who may not know, the atmosphere around us is actually the pressure of the air around us ........I'll add my own point of view in regard to my own fishing experiences as I type my reply.

Barometric pressure is a component of all weather conditions and plays a major and accurate role in forecasting weather changes and barometric fluctations lead to the notification of weather warnings such as a low front or a trough with a collision of fronts possible i.e. a collision air pressure may be imminent with the possibility of storm turbulance, and blizzards etc occuring.........

All of these are factors in themselves and can be compared with previous fishing experiences in normal* weather and in good and bad weather and days with bad weather pending....... In the latter case, fish come out and literally stock up on food to allow for the change in pressure which I beleve they can actually feel, just as we resist the urge to go out and more or less stock up and hybernate when the atmosphere outside doesn't suit us........In normal* weather most fish feed spasmodically according to need..... In fact on some days only a small percentage of a whole school will feed i.e. the fish that missed out on getting sufficient food will feed, whilst others will only take food territorally. - {Normal* weather is a reading of around 1016milibars*}

The longer the weather stays steady the more the bite slows down and that's why it pays to watch out for fluctuations occuring on either side from a normal reading......

Any fluctuations can be noted as they occur and a trend or a pattern can be pre-empted with fairly good accuracy based on previous experiences with fishing in all weather conditions and by continually noting what the conditions were and what the barometer showed when experiencing both good and bad results ..........

Experiences with previous tendencies and modern day weather forecasts are the basis for finding recurring patterns..... Patterns can be established with good accuracy only by hands on experience, provided of course that there are fish there in the first place and that you are fishing where the fish are or where they are likely to be after at least waiting for the best bite time for the particular species, rather than just fishing within certain hours....

The pecking order comes into effect dependent on depth of comfort for the particular predator species...... Otherwise, if all fish could handle all pressure on water at all depths, all small fish, baitfish, squid, prawns etc would be decimated and some species would be non existent.........

That is where nature and conditions come into it, making it impossible for all species to exist in the same places at the same time......

Changes in the atmosphere i.e. the pressure around us definately affects our habits and the habits and behaviour of insects and animals and the same air puts the pressure of the outside atmoshere onto water which governs the water depth fish can find comfort at...... Pressure imbalance and lack of depth has an affect on their swim bladders and extreme conditions are known to affect the digestive systems of natural estuary species.

Some scientists are way out of kilter and beg to be indentified as being different to others in their viewpoints but do have the time and the minds to experiment and particularly when given the resources and not having been swayed over to a certain direction.......

Scientific findings are often based on scientific knowledge inherited from science tutors and are not always based on repetitive practice in the field......In some cases where there may be a vested interest findings are not conclusive and often not final findings either..........

To refresh this topic, I add the relevant part of my reply to twin1's report of another very unsuccessful day of fishing the Harbour/Middle Harbour area.

Fishing is normally best during rising barometric pressure and for the first hour or two of falling pressure. Sudden changes in pressure usually see fish in feeding mode.

Fishing is generally always poor during low or constant barometric pressure.

The info below is about it in a nutshell :-

Steady rise continuing = best

Rapid rate of rise or rapid rate of fall = good until pressure steadies and bite starts to slow.

Ongoing steady pressure = poor

Falling pressure continuing = good at first and then changing to poor

In planning yor sessions, why not be guided by the barometer and then see if you do any better......Try and coincide your sessions with wind changes, particularly winds forecast to change to opposite directions and then look at tides........

Move upriver to get the same stillwater periods due to the tide delay, and when you arrive at a good performing spot, fish the early changes in either tide direction, and move again when the bite slows but stay on the same side where you got the results.....

Cheers

jewgaffer

Edited February 14, 2010 by jewgaffer

[marcel haber]

gOOD READING bYRON once again,

Can you please explain when you mention stay on the same side as where you got results what are you implying here.

Twin 1

[jewgaffer]

Hi Marcel, If you are fishing the Beauty Point side and finding fish on that side stay on the same side as you chase the stillwater up river... I fish the small sheltered alcoves as a circle Marcel and treat the angles of a bay according to wind direction.

Cheers

jewgaffer

[tide'n'knots]

Hi Marcel, If you are fishing the Beauty Point side and finding fish on that side stay on the same side as you chase the stillwater up river... I fish the small sheltered alcoves as a circle Marcel and treat the angles of a bay according to wind direction.

Cheers

jewgaffer

Hi byron, does this mean that we are to assume that the fish will stay on the same side of the river as they move upstream? what happens when they get to a spot like bar point? the best fishing at that spot is out in the middle of the river, and from there the river splits, right to spencer, straight ahead and to the left to berowra. I guess its pot luck at that stage.

P.S.

this is a top post by the way! I am slowly starting to get my head around this stuff and you just clarified it for me a little more. - I can be a bit slow to learn!

Pete.

[joel99]

A few things...

On the swim bladders, not all fish have them as they are used to control buoyancy. So for example in bottom dwellers like flathead the swim bladder theory is kinda nullified.

Also it would be interesting to see some controlled studies on this. But I would assume it would be much to hard to replicate or control any field studies, as you can't really just not catch a fish and determine that it was due to barometric pressure and they are not feeding. But then in doing a lab study you couldn't account for environment....

That said, I think it is important to fish as often or as little as you like and only take things like this with a grain of salt, it is pretty much only anecdotal evidence anyway. Not to mention you can catch fish at anytime of day under any barometric pressure in any weather

[jewgaffer]

Hi byron, does this mean that we are to assume that the fish will stay on the same side of the river as they move upstream? what happens when they get to a spot like bar point? the best fishing at that spot is out in the middle of the river, and from there the river splits, right to spencer, straight ahead and to the left to berowra. I guess its pot luck at that stage.

P.S.

this is a top post by the way! I am slowly starting to get my head around this stuff and you just clarified it for me a little more. - I can be a bit slow to learn!

Pete.

Pete You only get a couple of moves upriver following tide delayed still water particularly if you do well and stay in one spot and the tide picks up.... I've found it better to stay on the same side of drop offs into a channel where you did well and the bite goes off..... I follow the course of a channel and fish out from the most likely looking green markers on the same side of the channel and that can be applied to any area including an area with shallows on one side of the channel and rocks on the other side of it.

Cheers

jewgaffer

[jewgaffer]

............On the swim bladders, not all fish have them as they are used to control buoyancy. So for example in bottom dwellers like flathead the swim bladder theory is kinda nullified.

............But I would assume it would be much to hard to replicate or control any field studies, as you can't really just not catch a fish and determine that it was due to barometric pressure and they are not feeding. But then in doing a lab study you couldn't account for environment....

..........That said, I think it is important to fish as often or as little as you like and only take things like this with a grain of salt, it is pretty much only anecdotal evidence anyway.

...............Not to mention you can catch fish at anytime of day under any barometric pressure in any weather

Hi Joel Let's deal with these comments one at time and perhaps treat them as questions rather than comments.

1. & 2. ".......on bottom dwellers the swim bladder theory is kinda nullified"

I believe science has it that natural deep water bottom dwellers are not affected by barometric pressure and, because of their make up deep sea pelagics are not affected to the same extent as estuary fish precisely because of the depth of the water in their natural environment... On some days pelagics are comfortable going in an out of shallow wash areas but why then are they are not there all the time... there are plenty of estuary/deep sea fish in wash areas for food, still one would have to think that, because of whatever pressure on the water, the food can't always tolerate the wash area depths themselves.... I would say that was because of the affect of air pressure on shallow wash areas..... so they seek refuge areas that are comfortable for them where other fish can't get to them to have another natural reprieve for survival.

You could also ask why are marlin not active around the entrance of south west arm in the Hacking, the depth is there and the salinity is there. My hunch would be that the pressure on the way up river the pressure of air on water would not suit Marlin even at its most tolerable point.

To add further food for thought, over many years fishermen have found that barometer rising means fish are going to be rising. That has been found to be the case in my experiece as well and is in direct contradiction to any belief that low pressure does not cause fish to seek tolerance zones in deeper parts of the water column in accordance with the lowering of the pressure and not the rising of the pressure.

3. "......I think it is important to fish as often or as little as you like and only take things like this with a grain of salt..... "

The reason why so many fishermen, who endeavour to excell at the sport, go off a barometer's reading and it's fluctuations among other factors, is to find the best times to fish on the day and select the best locations to fish under the circumstances, based on their previous experiences in order to give themselves the best chance possible of success, and in my opinion they feel better in themselves knowing that successes only come out of the efforts that they themselves put into it.

4. ........."Not to mention you can catch fish at anytime of day under any barometric pressure in any weather"

What part of the day would that be approximately?

Cheers

jewgaffer

[Josh88]

Byron have you got a website that has accurate and regularly updated Barometric pressure info?

Cheers

Josh

[joel99]

Hi Joel Let's deal with these comments one at time and perhaps treat them as questions rather than comments.

1. & 2. ".......on bottom dwellers the swim bladder theory is kinda nullified"

I believe science has it that natural deep water bottom dwellers are not affected by barometric pressure and, because of their make up deep sea pelagics are not affected to the same extent as estuary fish precisely because of the depth of the water in their natural environment... On some days pelagics are comfortable going in an out of shallow wash areas but why then are they are not there all the time... there are plenty of estuary/deep sea fish in wash areas for food, still one would have to think that, because of whatever pressure on the water, the food can't always tolerate the wash area depths themselves.... I would say that was because of the affect of air pressure on shallow wash areas..... so they seek refuge areas that are comfortable for them where other fish can't get to them to have another natural reprieve for survival.

You could also ask why are marlin not active around the entrance of south west arm in the Hacking, the depth is there and the salinity is there. My hunch would be that the pressure on the way up river the pressure of air on water would not suit Marlin even at its most tolerable point.

To add further food for thought, over many years fishermen have found that barometer rising means fish are going to be rising. That has been found to be the case in my experiece as well and is in direct contradiction to any belief that low pressure does not cause fish to seek tolerance zones in deeper parts of the water column in accordance with the lowering of the pressure and not the rising of the pressure.

Jewgaffer, i'm certainly no expert on the matter, I barely even know what i'm talking about and I won't pretend to. I was just pointing out that the swim bladder theory that you talk about in the original post might not hold as much water as you think(pun intended ) as not all the fish that we target even have one. Furthermore (again this is just speculation) we know fish are very sensitive to their enviroment, and in saying this there would be a number of factors affecting everything they do, be it feeding or whatever. So it is hard to say that oh, the fish arn't biting today it's the air pressure again!

3. "......I think it is important to fish as often or as little as you like and only take things like this with a grain of salt..... "

The reason why so many fishermen, who endeavour to excell at the sport, go off a barometer's reading and it's fluctuations among other factors, is to find the best times to fish on the day and select the best locations to fish under the circumstances, based on their previous experiences in order to give themselves the best chance possible of success, and in my opinion they feel better in themselves knowing that successes only come out of the efforts that they themselves put into it.

Sorry, what I meant by this is: Friday arvo and you get let off work early. If the barometric pressures aren't the best, or aren't even favourable, this shouldn't stop you or make you think that you won't be able to still go fishing.

4.What part of the day would that be approximately?

Any part! That is my point!

Cheers mate, Joel