The moon's gravity is what causes it to affect the fish. It's the moon's gravity that causes tides. This is because of the pushing and pulling between it and the earth.
The new moon (when there is none in the night sky) and the full moon are the best moons for fishing as well as 2 to 3 days before and after each of those phases. At each of those phases the moon, the earth and the sun are in a perfect line with each other. This causes the pull of the moon to be altered at the most during these phases. This will also cause the highest and the lowest tides.
It is believed that animals will use the pulling affect of the moon's gravity like an alarm clock. For example, full moon in the spring is the peak spawning period, not just for fish, but for many other animals as well.
I dont know how well my explanation will help you. I'm sure someone may be able to explain it better.
Take a look at my old Cosmic Clock and Bass Calendar posted in General Discussion, 12 Jan '07.
Ps; I know this may be old stuff and confusing at first, but the answers are there to why bass do what when and where.Yes I can hear the chuckles all from CA. I sent a color photo to Jared months ago and color helps to understand the chart a little better.
Atmospheric pressure does affect air bladder pressure. Once a bass aclimates to a certain depth any change in air pressure affects water pressure slightly. That change is apparently enough to affect fish. Rising pressure drives them deeper, dropping pressure results in them rising higher in the water column. A steady high or low pressure allows them to resume normal positions and behavior.
It's been noted for millennia the moon affects humans too. Whether what we believe about a moon phase is the cause or not, there is something about it that does have influence on life on earth. It might be that a heavy surge in bass spawning occurs around a new moon simply because there's more light at night to help them guard nests by.
There are so many things we don't exactly know why animals do what they, however by observing we see them doing whatever it is they do. Tidal, solar, lunar and magnetic forces all influence behavior. It's been my belief when everything around a lake is active, so are the bass.
"any moon that holds water is a good time to fish", " the new moon is best", "the full moon is bad", "wind from the west, the fishing is best", wind from the east, the fishing is least", and the one that makes most sense " you catch fish from your living room chair".