Every tackle shop counter has a solunar table on it. Major periods, minor periods, a best-days-of-the-month star rating. It is one of the most widely consulted pieces of information in fishing, and it has been for most of a century.
Somebody finally checked it against real catch records.
The direct test
Quigley, Gonzalez Murcia and Kauwe took popular solunar tables and tested them against North American recreational freshwater trout catch data. The paper's title is the finding: the tables fail to predict fishing success.
The obvious objection is that trout in fresh water are not striped bass in the surf, and that is fair. But look at what the solunar claim actually is. It is not a claim about trout, or about tides, or about any particular fishery — it is the claim that a calculation from the moon's position predicts when fish feed, everywhere, in everything. A universal claim can be tested anywhere. Tested where the records were good enough to test it, it did not hold.
The control that closes the loop
The more interesting study is about pike.
Kuparinen, Klefoth and Arlinghaus logged 169 day and dusk catch records over 94 days of experimental angling on a closed German lake — no tides at all — and looked for a lunar signal.
They found one. Catch rates rose around both the full moon and the new moon. A twice-a-month pattern.
Sit with why that is a problem for both of the usual explanations:
- It cannot be tidal. There is no tide in a lake. Whatever the moon is doing to catch rates there, it is not doing it by moving water.
- It cannot be moonlight. Full and new are the two opposite extremes of night illumination. An effect that peaks at both is not an effect of how bright the night is.
In their model the whole lunar signal rests on one term — the one that peaks at both full and new moon, significant at p = 0.034 — while the other three lunar terms dropped out (p = 0.054, 0.429 and 0.157). The authors call it a clear relationship and suggest prey movements or some other lunar cue they did not measure. Our reading is more cautious: it is one 25-hectare lake, one summer and one term, and whatever it is, it fits neither of the usual explanations.
That is what a real control looks like: it does not prove the moon does nothing, it removes the two explanations everyone reaches for.
The part people get wrong about "moon phase"
There is a technical point underneath this that explains a lot of the confusion.
Two different lunar cycles run at once:
| Period | What drives it |
|---|---|
| 14.77 days | Tidal range — spring and neap |
| 29.53 days | Illumination — how bright the night is |
Those are physically separate. A model that encodes "moon phase" as one number on a scale has folded them together and thrown away the information that would let you tell which one is acting. Most fishing tools do exactly that, then report the blend as if it were a mechanism.
What actually survives
Something does survive, and it is worth having.
The moon moves the tide, and the tide moves water. That is not folklore, it is orbital mechanics. A spring tide near full or new moon means a bigger range, which means more water moving in the same six hours, which means faster current through the constriction you are standing on (Tabory, Inshore Fly Fishing). That is a real, large, predictable effect — and it is a current effect that happens to be scheduled by the moon.
Night illumination is real too, at the scale it deserves. Somewhere around a tenth of a lux on a clear full moon (Kyba et al. 2017), against far less on a moonless night away from town — and striped bass eyes work best in bright light (Horodysky et al. 2010). That is a genuine difference in how a visual predator hunts. It is also a much smaller and more conditional lever than a star rating implies. Cloud cover routinely erases it, and near a city, low cloud reflecting sky glow can light the night about as much as a full moon does (Kyba et al. 2017).
What does not survive is the step in the middle: that you can go from the moon's phase to a feeding window without going through the water.
What to do with it
Read the tide, not the phase. If you want the thing the moon is genuinely doing, look at predicted range and predicted current for the day you are fishing. That is the mechanism, stated directly, without the intermediate step that keeps failing tests.
Treat a full moon as a light condition, not a rating. It changes how deep fish sit and how visible your presentation is. That is a tactical input, not a score.
And be suspicious of your own memory here. Solunar beliefs are unusually good at surviving because a major period is several hours long — you will always be able to find a good session inside one. That is not evidence, it is the width of the window.
How StripedLines uses this
StripedLines is built for striped bass. It shows the predicted tide and current for your day, and the sun and moon, so you can read the moon's real levers yourself: the current it drives and the light it gives.