Fishing: Full moon's influence does not always leave fishermen howling

NZ Herald

9 Jun, 2017 10:11 PM5 mins to read

The best days for fishing are around the phase of the new moon. Photo / Geoff Thomas

It's a full moon today and many fishermen will look at the sky and shake their heads, for it is a common belief that fishing is always hard at this time.

Is it because the bright conditions cause small fish to hide away from predators, or do they feed at night in the brighter light? Or, is it the effect of the moon's gravitational pull?

Nobody knows, but as with all fishing there is no shortage of theories.

Such discussion does bring to mind a conversation with a well-known fishing personality who produced regular Maori fishing calendars, and these are based solely on the moon and its phases.

"I had always marked the day of the full moon as a bad day to go fishing, but we went out the other day on the full moon and cleaned up -- so I changed it in the calendar to a good day," he said with a chuckle.

There is a variety of such publications, and surprisingly they do not all agree on which days of the month are best to go fishing.

But generally the two weeks around the new moon are better than the other two weeks.

One aspect of the moon's influence is the bite times, which are referred to every week in this column.

There is no doubt that the moon does influence the feeding patterns of all animals, and fish. But this is determined by the position of the moon, more than its phase.

There are two "bite times" during every 24-hour period, and these refer to when the moon is directly overhead and underfoot on the opposite side of the globe.

The time when the moon is overhead is the major bite time which could last for an hour or more.

All experienced anglers seem to agree that fishing is also better when the moon is visible in the sky, not just at right angles.

The minor feeding period is when the moon is underfoot, and is much shorter.

Of course there are other factors that influence how well fish bite -- local conditions like time of day, state of tide and weather.

But when all the stars line up and you get a tide turn, a major bite time at dawn or dusk and friendly weather then it should be one of those memorable trips.

Then there are the trips which nobody talks about when the fish box comes back lean or empty, but philosophical fishermen will put this down to "paying your dues".

And it always does balance out. For every red-letter day there will be average ones.

The moon has other influences, not just the "loony" label applied to strange behaviour said to occur around the full moon.

Native people from Maori to North American Indians understood the influence of the moon, and used a similar lunar-based calendar to determine the best times for planting crops, hunting and fishing -- hence the Maori Fishing Calendar.

If fishing is slow on the day of the full moon, there is no reason why fishing at night can't be tested.

Night fishing can be very good at any time, but a large moon will produce enough light to see what is happening on a boat.

And it is always a great time to be surfcasting on Northland or Bay of Plenty beaches.

Snapper will move into shallows to feed at night, coming within range of surfcasters; and with a fire burning driftwood and a grill with some sausages sitting over coals scraped out to one side it is a nice way for a family to enjoy the beach.

Because the moon circles the earth every 27.32 days the date of the full moon does not correspond with monthly cycles, but it does affect tides through its gravitational pull.

The oceans are like giant jellies which wobble when affected by the moon's pull, and it is the resulting movement of water that creates tides.

The distance of the moon from the earth also affects tides and as the moon travels in an elliptical orbit around the globe, its gravitational influence varies.

The average distance from the earth is 384,000km but this varies by as much as 50,000km so we get the biggest tides when it is closest, and smaller tides when it is farthest away.

As a result we experience the biggest tides of the month around the full moon for six months of the year, and then around the period of the new moon for the other six months.

When planning a fishing trip, it is easy to look up the biggest tides and these will create the strongest currents, which are the best for fishing.

Or perhaps one should just go fishing when the lawns are done, the family is happy and the wind is not blowing too hard.

• Freshwater

There are no tides in fresh water, but the moon does affect the behaviour of trout and their feeding patterns. This is illustrated by the lack of food inside a trout's stomach when caught; it may not have eaten for days.

The bite times and good-bad days which apply at sea can also be referred to when trout fishing.