Ken, a very enjoyable read! Thanks. It adds valuable information by following actual crappie movement.
Alas, the author and the researchers still make a "boo boo" by conflating barometric pressure with good and bad fishing results (in the researcher's case, netting crappie for official head counts). The crappie are influenced by the weather patterns associated with different readings, changes in readings too, but it has nothing to do directly with the tiny bit of position adjustment a crappie (or any fish) would have to make in the water column to offset the effects of changes in pressure. This would only take, at most 99% of the time, well less than a foot up or down change in position. Fish, most all of them, do this every day routinely as they adjust to temperature, light, wind and waves, following food sources, and so on. A largemouth bass might swim up to the bank in 12" of water for breakfast, then spend lunch at 15 feet, then move again at night.
What the research does show, irrespective of how well they are biting, is how crappie tend to move based on temperature and other weather conditions. The research is great and it shows us the patterns of white crappie related to when they move, in what direction and the associations with weather.
The barometric pressure readings are simply measuring the tendencies toward weather shifts and the readings do a great job of predicting weather. Barometric pressure does work . . . for determining weather patterns.
One quick example would be something that happens almost every summer. On TV, the local weatherman will be trying to give us some encouraging news related to our hopes for a break in the temperature from the 100 degrees area. It's as if all of us humans living in Texas don't know that it gets hot and stays hot in Texas from June through August. Every year! Yet, it is ritualistic for the weatherman. So, he or she will say this: "You can expect temperatures to stay hot with no rain in our forecast, no relief in sight . . . until the high pressure system sitting atop of us breaks up." So, for us fishermen, this means that a high barometric reading, in say July, means that the waters will continue to warm, that there won't be a cloud in the sky, that winds will generally be lower than what we had in the spring and more. These things we KNOW affect fishing and how we have to fish. Fish, too, will then arrange their days accordingly. But, to the weather.
Pressure itself doesn't affect them much physically, not if rising or sinking a few inches negates the effects of changes in pressure. It doesn't make them hungry or not so.
It's all about weather conditions: seasonal tendencies owing to water temps and length of daylight hours, bait fish keeping out of sight in clear skies and calm waters to keep from getting eaten by prey fish, prey fish following the bait fish and the "food chain," seasonal water temps affecting metabolic rates of fish, spawning activity movement, and more.
Brad
