Much has been written, and even more has been discussed about the effect of moon phases on fishing and in particular billfishing. While most theories converge upon the idea that as the moon gets brighter – and therefore particularly around the full moon – the predatory fish are more able to hunt effectively at night time. When they hunt, usually they catch and eat – so anglers end up the next day pursuing billfish that have been feeding well and so not that aggressive for another meal.

While this is a rational argument, and does make some sense – and no doubt moon phase is a variable in the catch rates – there is also evidence that it is not a very strong factor for raising high numbers of sailfish at least in Guatemala. In the last two years when records were set (124 on conventional, 27 on the fly by single boats in a single day), the periods happened to coincide with (or very close to) a full moon. There was a study done that that collated statistics over a decade in Australia – and which showed some correlation. The remarkable finding however was that there was correlation for the new moon (yellowfin, Mahi) - but also for the full moon (Black Marlin) !!

So much for that theory!

Why such different results?

According to this study’s authors, currents effect the fishing significantly, and as we all know, the biggest tides occur everywhere during the full and new moons…….and different species react in different ways to the changing of the drive of the currents and the effects on the concentration or otherwise of baitfish. So a summary from our experience is that certainly the new moon is the most popular period for anglers to visit Guatemala for sailfishing, and there is some rational to the argument – but it is likely (and local opinion) that other factors such as weather front/stability, strength of current, location of blue water etc are probably more influential variables and in the fleets’ experience have a greater effect on the number of sailfish raised on any particular day.