Andy Wass holds a fish. Credit: Courtesy of Leighton Wass

I finally saw it in print. Someone besides me using moon phases to predict good fishing days. That’s one giant leap for mankind — and me.

I have prattled to others for years about using the solunar calendar to pick my fishing days, so I feel better now. Let me tell you why.

Most anglers have seen the many charts and tables that espouse the theory that they’ll be over the moon if they fish based on where the moon and sun are relative to the Earth. Some folks think you could wind up howling at the moon instead.

After some research, I can offer a few facts as to what the theory’s originator, J. Alden Knight, was thinking back in 1926.

Solunar theory centers around the gravitational pull of the moon and sun on the Earth. The closer the orbs are (full moons and new moons) to each other, the stronger the influence. Solunar theory says it’s at these times that living things, including fish, show greater activity.

Based on the position of the Earth and moon, two “major” feeding periods, lasting two to three hours each, and two “minor” periods, around one hour each, are calculated for each day. These occur in both the oceans and freshwater, but I am limiting my discussion to freshwater.

Knight tested his theory by studying approximately 200 fish caught that were either particularly large for their species or were caught in large numbers. Reportedly, 90 percent of the fish were caught during a new moon.

You may ask, what on earth does gravity have to do with feeding fish? That question remains unanswered.

Others have used anecdotal fishing records to test Knight’s theory. Three of four results I found between 1986 and 2016 indicated support for the concept of large fish caught around the new and full moons.

One fisherman, though, found no connection after looking at thousands of bass catches. He believed other factors were involved and that gravity wasn’t enough to affect bass.

It doesn’t appear that there has been a lot of hard scientific research done on this topic but there is enough anecdotal information to go around the moon several times.

Some solunar tables list a fish rating of 1 through 4 for each day, where a “4-Fish Day” represents the best fishing day and a “1-Fish Day” is the worst. For example, the day I wrote this was a “4-Fish Day” (Why was I not out fishing instead of writing?) because it was a new moon phase. If you want to narrow it down further, the major (best) and minor (next best) time periods are also provided.

A graphic shows the best times to fish based on the moon.
“The screen shot of a solunar chart for May 30, 2022, predicts a “4-Fish Day” (best fishing) with major and minor periods of fishing. Credit: Courtesy of Leighton Wass

Since solunar theory covers the entire year, let me give you some stats for ice fishing this past winter at Lake Champlain in Vermont. My son, Andy Wass, and several of his cohorts iced in excess of 130 togue (lake trout) in just nine fishing trips.

These hard-nosed ice anglers went fishing on days that they could and didn’t purposely fish the moons. Two of the trips occurred on “4-Fish Days” and produced a total of about 20 togue.

Six of the excursions were on “3-Fish Days” and accounted for just over 100 fish, including the largest. Of the nine trips, only one was a “1-Fish Day” and fishing alone that day, my son reported only one small togue. These lake trout averaged 6-7 pounds, with the largest weighing in at 15 pounds.

Two of the ice fishing trips occurred during the full or new moon phase, while a third trip took place three days following a new moon — the day the largest fish was iced.

Is Lake Champlain rife with togue? Absolutely! Is this scientific reporting? Absolutely not. Do these numbers indicate that fishing may be better on or near a full or new moon? You bet your sweet bippy they do.

Now consider the data that I compiled from my fishing journals dating back to 1977 in which the largest brook trout, salmon, togue, walleye and rainbow trout landed in my net. It includes brook trout up to 20-plus inches, togue up to 18 pounds, a salmon over 7 pounds, a 4-pound rainbow and a walleye of almost 9 pounds.

Out of 16 large fish, four were caught on the day of a full moon or new moon, five were landed within two days of a full or new moon, and two were netted within three days of a full or new moon. Five of the 16 bruisers were not caught close to a full or new moon.

Summing up those results with my abacus, it looks like 11 super-sized fish out of 16, or 69 percent, were caught in close approximation to the full and new moons. One might ask again, just how scientific are these numbers?

Actually, even though the quantity of fish involved is not large, my stats are meticulous, and thus I believe again that these numbers strongly indicate a correlation between moon phases and fishing results.

One big factor that is not taken into account with solunar predictions is local weather, which also can have an impact on fish feeding activity. I believe that is why I have sometimes done poorly when fishing on some “3-Fish” and “4-Fish” days.

Adherents of the solunar theory can plan long-range fishing trips using these charts. For example, when I plan a summer fishing excursion in January, I religiously check the solunar calendar for the “best” fishing days in the month that I expect to fish and then base my reservations on that data.

Does it always work out? (Is there a man in the moon?)

I’m not really asking for the moon here, just suggesting that the solunar calendar might work for you, too.

Leighton Wass, Outdoors contributor

Leighton Wass grew up in Southwest Harbor and graduated from Norwich University with a B.S. in science education. He taught high school biology in Vermont for 33 years and also is a freelance writer. At...