Anglers have followed John Alden Knight's solunar theory since 1926.

As I sat down to write this article, the moon began to come up. For several nights, the moon had been brighter and brighter as it made its way toward a full moon. After many years of gazing into the sky as a kid and now as an adult, I still find myself wondering just how much influence this great object in the sky really has on our lives and the world around us, especially when it comes to fishing. As an angler, I’ve built some unscientific opinions about how the moon affects my fishing, in particular the species that I – and I’m sure many of you – seek on a regular basis. 

Earlier this year, we celebrated the 50th anniversary of putting a man on the moon. Many documentaries were aired on television, recalling that event on July 20, 1969.

It caused me to wonder again: How much does the moon really matter in fishing?

As anglers, we are naturally curious about anything that might help make our fishing trips more productive. As long as I can remember, there have been moon phase calendars that predict good fishing (and hunting) times. But, I finally asked myself where these came from. Who decided these were the best times and why?

A quick search on Wikipedia and review of an article that Steve Quinn wrote for (April 29, 2015) revealed that in 1926, a man named John Alden Knight developed a theory that there were peak times to fish and hunt based on the alignment of the sun and moon. He later published and patented a set of tables that predicted those major and minor times when fish and game might be most active.

Knight’s solunar theory has been followed by anglers and hunters alike for many years since. Peak times are based on when the moon is directly overhead or underfoot of a given location along a reference longitude. The minor times were developed based on when the moon is at a 90-degree angle to that location. There are a lot of experienced anglers and hunters who follow these solunar predictions as a guide to when their chances of success might be best.

Although I didn’t find much in a shallow search on how Quinn developed his theory, I trust that there was enough scientific data collected to show a correlation. In short, this means that there really could be some merit to those times that now can be accessed through apps, websites, literature, etc.

 I must admit that I personally don’t follow these solunar times religiously. I oftentimes don’t get to choose exactly when I’m going fishing. Most anglers have windows of opportunity to fish, such as weekends or scheduled off-days. Tournament anglers have to fish on the days that the events are scheduled. Tournaments start at safe light and usually finish around 2 p.m. or 3 p.m. In my opinion, there are countless other variables at play that can dictate success on the water. 

First, you have to be around fish. Sounds simple, but you have to find fish to catch them; then, there is weather – a major factor with a multitude of variables that can change by the hour on any given day. Fishing pressure, seasonal phases, bait selection and presentation, hydropower generation schedules, the list goes on and on.

So the solunar periods fall pretty close to the bottom on the totem pole for me personally when fishing, but don’t let that discourage you from conducting your own personal experiments with the solunar periods. 

I do believe that they can influence fish to feed better if all other variables are fairly consistent. If you keep a fishing log, it would be fun to write those periods down in comparison to your fishing day and see just how much it mattered. To be objective, you would have to consider as many variables as possible, including those mentioned above, and make sure something else wasn’t a driving force in your success.

A similar study done by Ralph Manns was mentioned in the previously referenced article. He ran statistical data based on 2,500 fishing trips and found some correlations with the solunar periods, especially during times of the year when the bass feed more heavily.

Moon phase is a little bit different beast to consider. The gravitational pull on the Earth is greater during full moons and new moons because those are the times when the sun, moon and Earth are aligned. The best evidence of this effect is in the tides. Tides are stronger during the full moon and new moons because of the extra gravitational pull from the sun and moon together. As we consider the freshwater system in Lake Martin, that gravitational pull may not be visible in changing water level like saltwater tides, but it’s still there. 

Then there is the simple variable of light. We’ve all seen just how much light a full moon produces and just how dark it can be during a new moon. Light is a driving force in Nature, whether from the sun, a full moon or a reflection of light by the moon. In my experience traveling around the country chasing bass, I believe full moons and new moons can be driving forces in bass activity.

For example, bass are likely to spawn at certain times based on a number of factors, one being the photoperiod (day length); another is water temperature, which generally falls in close range year after year, depending on how far north or south I am; and then, there is moon phase. For me, Florida is the best example of this. Unlike a lot of places in the country, the water temperatures in Florida are in the prime range for bass spawning (60 to 75 degrees) for several months of the year. Temps don’t generally fall below 60 degrees for very long, even in winter, so the moon seems to be a larger factor in triggering the fish to start moving up.

In other areas of the country where the windows of prime temperature ranges are smaller, the full moon and new moon seem to have less influence, but if the water conditions align with a full or new moon, it’s almost a given that a large group of fish will be moving up to spawn. Keep in mind, though, that fish activity in the spawn is less about feeding and more about making more fish. 

I’ve seen a similar effect on bass forage – such as shad, bream and crawfish. Shad and bream spawns seem to be stronger during full moons, and although I don’t know much about crawfish rituals, I’ve seen the bass gorge on craws around full moons. Increased activity by the bass’ favorite food sources results in more chances to feed.

Are the forage active because they are in the act of reproducing? Or are they just more active because of the moon?

I’ve also witnessed the mid-day bite that’s associated with a full moon. In this case, I’ve wondered if that was driven by the effects of the increased gravitational pull or just because the fish fed heavily in the middle of the night; and then again, during the middle of the day, once their food had been digested. The solunar tables tell us that the best bite is mid-day during a full and new moon. In that case, it would be hard to argue with the tables.

Wildlife are active at night during a full moon, so it wouldn’t be far-fetched to think that after being up all night eating, fish might decide to sleep in and be hungry a little later than normal during the day. Whatever the case, this is the one time that I feel that I can count on the effects of the moon to influence bass activity.

This also is a time when gravitational pull is greatest and could possibly be a strong enough factor to compete with weather and other variables. We do have to be around them to catch them, though, so location still matters.  

In the end, after doing a little more research and considering personal experience, I seem to have come to the same conclusion that many others have when it comes to the moon: It does matter, but it’s very hard to say how much.

I, personally, am not ready to only fish when the solunar tables tell me the fish are biting. I’m going when I get a chance to go or when I’m scheduled to go. And I will consider the weather, the time of year, water temperature, the type of fishery, water level, generation schedules and a few other things; and then, I’ll worry about the moon.

Unless, of course, it’s close to the spawn.


Greg Vinson is a full-time professional angler on the Major League Fishing Bass Pro Tour. He lives in Wetumpka and grew up fishing on Lake Martin.