Quality Fish versus Environmental Conditions

Background:
A few years ago I kept an extensive fishing log using Microsoft Excel. For each fishing trip I took I logged the date, air temperatures, water temperatures, wind direction, barometric pressure, fish species, moon phase, and so on. Here's a screen shot of what that fishing log looked like:

The log continued for several pages to the right, which included various environmental aspects/trip information, and even scrolled down for 130 trips. The log also contained a locations column which I removed to protect a few smaller bodies of water that I enjoy fishing. The columns are color coded by location however, for example the red indicates a trip to a local warm water discharge. I kept this sort of fishing log for three years before I realized that I wasn't gaining much or learning anything from keeping this amount of information. I crunched the numbers each year, comparing environmental factors to numbers of fish, size of fish, etc. using scatter plots and other analytical tools. In the end I discovered that very few environmental factors were directly related to fishing success, even despite the common theories of wind affecting fishing ("Wind from the west, fish bite best. Wind from the North, don't go forth. Wind from the south, blows the bait into their mouth. Wind from the east, fish bite least."), barometric pressure ("High pressure makes fish feel full, therefore they don't eat as much."), moon phases (Excellent, Good, and Poor moon phase charts you see in magazines and online.), etc.

So what's the point to all of this? Well, a few months ago I had a conversation with a fellow fisherman who seemed to believe that we were catching more quality fish during certain environmental conditions. I told him about the log that I had kept in years past and that I hadn't found any correlations between environmental factors and fish in the three years I had kept my log. In short, that conversation sparked my interest once again. I began to question myself, Did I really know what I was doing three years ago? Was blind luck a factor that I had overlooked?


The Work Begins

This morning I began compiling a folder of fishing pictures from 2014. I only collected pictures of fish I deemed as "quality fish", which would help me cut down on the amount of data I had to collect and analyze. This time around I was really only concerned about what makes the "Big Fish" bite. I began by choosing a minimum length requirement  for each species of fish. This limit was based on sample size and quality. For example I set a limit on largemouth at 20", which gave me a sample size of 10, If I had set the limit at 18" my sample size and work would have doubled.  Once I had the folder complete I opened a spreadsheet in Microsoft Excel and began entering the information that each picture provided.  Here is one example:

From this picture I can see that the largemouth went 20.5" and was caught September 9, 2014 at 17:38 (5:38pm). I went through each picture and entered the Species, Length, Date, and Time into the spread sheet. After I had collected all of the data from the pictures I went to www.wunderground.com and began looking up the weather for each day in the "historical records". From the website I collected the data that I thought might be useful such as Wind Direction, Wind Speed, Humidity, Pressure, and Moon Phase Data. At this point I had an Excel Spreadsheet that looked something like this.

(I collected samples for 49 fish, ranging from trophy gar, flathead catfish, drum, largemouth, smallmouth, etc. )

Now the work began! I began by categorizing each factor....

Wind Direction became North, South, East, and West: These were determined by the predominant wind direction during the entire fishing trip.

Wind Speed became Calm, Moderate, and High. I deemed calm as wind speeds under 5mph, moderate as 5-15, and high as greater than 15mph.

Pressure became Low and High. I chose 30 inches of mercury to be the determining factor. Most people would argue that the pressure at sea level (29.92) would determine high or low pressure, however,  for my purposes I chose to round up slightly.

Humidity became Low, Medium, and High; I simply divided 100 in three parts....low became humidity of less than 33%, medium became humidity of 33-66%, and High became anything greater than 66%.

Moon Phase became New, First Quarter, Full, and Last Quarter. These were determined by rounding.


Once I had categorized all of the factors I crunched the numbers as a whole, not distinguishing between species. I had collected data for 49 different fish and the results were as follows:

I found this rather surprising, typically I don't see such a strong correlation to one wind direction over the other. Wind from the south certainly produced more quality fish than did any other wind direction. As the old saying goes "Wind from the south blows the bait into their mouths", and it certainly did. However the saying "wind from the west, fish bite best" didn't pan out so well here. Of course these are only my findings, not to be taken as a fact. Its possible that the wind in Ohio during 2014 blew from the south more often than any other wind direction.

I caught fewer quality fish during high winds (15MPH+), and to be fair if I knew the wind was going to be greater than 20mph I probably stayed home. I am somewhat surprised at the fact that moderate winds more than doubled calm conditions when quality fish were concerned. When you think about it though, a slight chop on the water that is produced by a 10mph wind conceals a lot of sound and vibration that anglers give off when fishing. Maybe, just maybe, the larger fish weren't as shy on those particular days.

 This is very surprising to me....when I crunched the numbers from previous years the one thing was constant was that low pressure was directly related to more fish per trip. Now its possible that if I had ran data on all of the fish I caught rather than just the quality fish, that low barometric pressure would still relate to those trips where I had caught more fish. At almost 4:1 high pressure produced quality fish over low pressure in 2014.

 This is the first year that I have looked at humidity as it relates to fishing. I had no preconceived notions when I began running the numbers but it does appear that the higher the humidity, the better your chances are for catching quality fish. 


Now this is the one we see every time we look at a magazine and see a calendar with "Excellent, Good, and Poor" marks. Typically the Good/Best/Excellent days come around the quarters and the poor days occur during the new moon phases when the moon is the darkest. I could go on to explain how they come to categorize the days further but one look at the graph above will tell you all you need to know about how accurate those calendars are. The new moon phase was far from the worst moon phase when pertaining to quality fish. While doing research I came across another article written on moon phases and fishing activity....http://www.anglerguide.com/articles/522.html.....The author too had kept a log and discovered that the solar lunar/fishing calendars where bogus. However, in time he came to prove that the moon did have significant impact on fish activity.

So what does all of this mean? Well nothing really, I mean sure it can be speculated that south winds are the best winds to fish, and maybe a full moon produces trophy bass after sunset (I haven't ran specie specific numbers yet...but I will soon!), maybe low pressure produces more fish, big fish feed on windy days, and so on. However, the one thing that I can tell you with certainty is that your not going to catch fish from your couch. Don't look at a calendar in a publication and sit at home because it says that the fish aren't going to bite. Fish when you can, fish often, and you will catch fish there is no denying that. With that said, I didn't write this to tell you that there are no patterns, and that weather doesn't influence fish activity because it does. What I am saying is that you can find a pattern that produces big fish for you, maybe even on a specific body of water. When your time off and those weather/environmental patterns line up, get ready to target those big fish.