Solunar Calendar
Solunar theory, developed by John Alden Knight in 1926, proposes that fish and wildlife are more active during specific daily periods tied to the Moon's position. These periods — two major and two minor each day — are calculated from the Moon's upper and lower transit times and its rise and set times. Many anglers and hunters use solunar tables to plan outings.
Major Periods
The two peak activity windows of the day, each approximately two hours long. They occur when the Moon crosses the observer's meridian (upper transit, Moon directly overhead) and when it crosses the antipodal meridian (lower transit, Moon directly underfoot). Major periods are considered the strongest feeding times.
Minor Periods
Two shorter activity windows of roughly one hour each, occurring at moonrise and moonset. These are weaker than major periods but still considered better-than-average windows for wildlife activity.
Solunar Rating
An overall assessment of the day's activity potential — Strong, Moderate, or Weak — derived from how closely the solunar periods align with sunrise and sunset. Days when a major period coincides with dawn or dusk are rated Strong, as peak solunar activity compounds with the natural crepuscular behaviour of many species.
Activity Chart
The chart displays the full 24-hour day as a horizontal timeline. Each solunar period is drawn as a shaded band centred on its peak time — major periods appear as taller, more prominent bands and minor periods as shorter ones. Vertical markers for sunrise and sunset are overlaid so you can immediately see whether any solunar window falls close to the natural light transitions that drive crepuscular behaviour. The width of each band is controlled by the pad setting.
Period Pad
The radio buttons — 30, 60, 90, and 120 minutes — set the padding applied symmetrically around each solunar period's centre time. A pad of 30 minutes means each window spans ±30 min (one hour total); a pad of 120 minutes spans ±120 min (four hours total). Increasing the pad widens the shaded bands on the chart and broadens the overlap windows shown in the morning and evening tables. A narrow pad highlights only the tightest coincidences with sunrise and sunset; a wider pad is more forgiving and useful for planning longer outings where an exact peak time is less critical.
Limitations
Solunar theory is empirical rather than rigorously scientific. Weather, water temperature, barometric pressure, and habitat conditions all influence wildlife activity and are not accounted for by solunar tables. The periods are best treated as one input among many rather than a definitive forecast.