Figure 6. Factors influencing the strength of the relationship between the lunar cycle and number of fish caught.

Mean R² values are for 100 model runs of 30,000 (latitude and month) or 20,000 (length) randomly selected daytime caught fish. All models are of the form y = a+xcosine2θ, where y =  number of fish caught and θ is the angular equivalent of lunar day. Value inside bars is N. Scatter plot for Latitude is the mean R ² when June and October are excluded from regression models.