Weather change = lockjaw

[J.A. Veil]

Last evening, the weatherman called for rain most of the day on Tues, so I had no plans to fish today. However, when I woke up, the sky was blue and the winds were not too strong. After breakfast, I quickly loaded up the gear and drove to Jonas Green park.

Half an hour later I started casting, with the sky still blue. In the first 30 minutes, I caught one 16" pickerel and had at least 5 other bites. One bite attempt left me laughing out loud. I was in 3 ft of water and had just retrieved the lure to boatside. As I lifted the lure out of the water, a fast-moving pickerel jumped clear of the water and tried to hit the lure only 5 ft away from me. It missed -- I just sat there laughing at the spectacle.

Then the weather changed as the front pushed through. The sky became grey, and the wind got stronger. I stayed at it another hour without a single bite. It is frustrating to know exactly where the fish are and know what they have been hitting. But Mother Nature changed the atmospheric pressure as the front came through, effectively silencing the dinner bell.

After that hour I paddled back to the park. The waves were now 1.5 to 2 footers, plus the wind direction had shifted such that I had to paddle into the waves both coming and going. The drizzle started just as I finished loading the kayak into the back of the van. At least I got in 30 minutes of fun fishing this morning.

[ictalurus]

I love spur of the moment trips like that. It also cracks me up when fish miss. It's somehow reassuring to know that there are athletes and klutzes in the fish world, too.

I'd love to know why fish turn off with weather changes. I have yet to see a good explanation. The water buffers temperature changes, though enclosed, shallow areas probably respond faster to changes in air temperature. I'm not sure why relatively subtle changes in air pressure would matter. I think any change in air pressure is relatively small compared to the weight of the overlying water. I also don't understand why my aquarium fish don't seem to behave any differently, but they're pretty well trained to come out at feeding time.

[HJS]

Thanks for the report. At least you're finding some pickerel in the Severn. I'm a Magothy man myself but I haven't heard about any pickerel action in the Magothy yet this fall/winter. Next good weather day I might have to launch at my bro-in-laws place on the Magothy and see if I can find any pickerel. Some years action is good there , other years not so good. Seems to go in cycles depending on when the last good hatch was.

[ronaultmtd]

I love spur of the moment trips like that. It also cracks me up when fish miss. It's somehow reassuring to know that there are athletes and klutzes in the fish world, too.

I'd love to know why fish turn off with weather changes. I have yet to see a good explanation. The water buffers temperature changes, though enclosed, shallow areas probably respond faster to changes in air temperature. I'm not sure why relatively subtle changes in air pressure would matter. I think any change in air pressure is relatively small compared to the weight of the overlying water. I also don't understand why my aquarium fish don't seem to behave any differently, but they're pretty well trained to come out at feeding time.

Bill- I think about the bite turn on and turn off reflexes all the time- you know the fish are there as you can see them on the sonar- just exactly what weather factors play what part in the fish reflex feeding habits? Is it barometric pressure, is it sunlight angles, we just don't know the answers to so many of the basic factors that trigger the fish to feed- I have seen the color of a lure determine your luck- one I lost a certain color lure I was SOL- fished the exact same lure in a different color and got nothing. I know for certain that tides affect the bite, but I've caught fish at low tide, high tide and slack tides, so while the phase of tides are a factor but you are never certain any particular phase of the tide will be the right one-early morning, late evening always seem to be the "magic moments" of fishing- when the light is dusky dark but changing- and a single bite can be the difference between a great day and a bummer of a day on the water-

[ictalurus]

You're right, Ron. Studying fish and their feeding habits on those small time scales is incredibly difficult. After my post, it occurred to me to do a quick search of the aquaculture literature since understanding fish feeding patterns is important for maximizing growth and minimizing waste. I didn't find many studies there, either, and the results of the few I did find were conflicting.

Most of the other studies I found that mentioned barometric pressure were tagging/tracking studies. I didn't do a formal analysis, but the studies where barometric pressure was a significant variable tended to find that fish tended to move more when the pressure was changing (sometimes when the pressure was high, as well). The coolest paper was a note from a juvenile blacktip shark tracking study from Terra Ceia Bay in Florida. They tagged something like 40 juvenile sharks and used 25 receivers to track the sharks' position every 15 minutes. Thirteen of the sharks were in the bay before Tropical Storm Gabrielle hit Florida in 2001, and all the sharks left the bay in a pretty coordinated fashion right before the storm made landfall. A similar but less distinct response was observed for Hurricane Gordon in 2000. The researchers really weren't prepared for this, but they had enough data on environmental variables to come up with a reasonable theory. The change in hydrostatic pressure (pressure felt by the sharks in the water) due to the storm was less than the change in the change in hydrostatic pressure during a tidal cycle, so it seems unlikely that the change in pressure alone was enough to make the sharks leave. However, fish without swimbladders, such as sharks, are sensitive to tidal cycles and can anticipate the changes in pressure associated with the tidal cycle. The physiology of the inner ear of some sharks makes them sensitive to subtle changes in hydrostatic pressure. The change in pressure cause by the storm deviated from the normal pressure pattern associated with the tidal cycle, which may have prompted the sharks to leave. I don't know if the same mechanism would apply to fish with swimbladders, but that paper was the closest study I've found where the authors tried to come up with a physiological basis for explaining the behavior. So, maybe in John's case, the pickerel quit biting because they were in the process of moving to deeper water because low tide came early in terms of the pressure they felt.