Moon Phase Fishing Calendar: What Is Solunar Theory?
This moon phase fishing calendar explains solunar theory, the idea a lot of anglers plan trips around: that fish bite more at certain times of day tied to where the moon is overhead. That idea has a specific history.
What is solunar theory?
Solunar theory was developed by John Alden Knight in 1926, who published the first solunar tables in 1936. It combines fishing folklore with the sun and moon's positions: the core claim is that fish and other game feed more actively when the combined gravitational pull of the sun and moon is strongest, particularly around new and full moons, and during specific windows tied to where the moon is relative to your location.
Major and minor periods
Solunar tables split each day into "major" and "minor" feeding periods. Major periods (roughly two hours) are centered on the moon being directly overhead or directly on the opposite side of the earth ("underfoot"). Minor periods (roughly one hour) are centered on moonrise and moonset. Activity is traditionally said to peak when a major period lines up with sunrise or sunset.
Does the science back it up?
Being straightforward here: there's no peer-reviewed scientific consensus validating solunar theory. It's built on anecdotal reports from generations of anglers rather than controlled studies, and the underlying astronomical calculations are complex enough that different solunar table providers can disagree with each other. Treat it as a long-running fishing tradition worth factoring in for fun, not a guaranteed method.
New moon and full moon effect
The theory's strongest claim is that fishing tends to be best around new and full moons, when the sun and moon's gravitational pull combine most directly. You can check the current phase with the Moon Phase Calendar tool, or look up an upcoming new or full moon date on the Full Moon Calendar.
The history and mechanics of solunar theory above are drawn from published, cited background on John Alden Knight's original work. We haven't found controlled scientific studies confirming the theory, and the source cited below explicitly notes inconsistencies between different providers' solunar calculations -- we're passing that caveat along rather than presenting the theory as settled science.
Source: Wikipedia, Solunar Theory.