Tides and the Redfish

by Captain John A. Kumiski

Tides affect fish. Fishermen need to know how. This short article discusses in a general way the effects that tidal changes have on redfish behavior.

Tides have the highest highs and the lowest lows when the moon in new or full, respectively. As the tide changes we get very strong currents flowing because a lot of water is moving. We call these extreme tides spring tides. They occur because the earth, moon, and sun are all in a line. The combined gravity of the moon and sun work together to produce spring tides.

The difference between the height of the water at high and low tide is called the range. The tidal range is greatest during spring tides.

Follow the tides to find fish.
Doug Stamm/ProPhoto

Tides have the lowest highs and highest lows (smallest range) during the quarter moon phases. The current flows during tidal changes are weak since relatively little water moves. We call these tides neap tides. They occur because the moon, earth, and sun form a right angle with the earth at the vertex. The gravitational attraction of the moon and sun work against each other now, resulting in these weak tides.

In most areas you find two high tides and two low tides per day. One high is higher than the other, and as you might guess, one low is lower that the other, too.

The time and height of tides can be predicted years in advance. The government publishes tide data in a book called the Coastal Pilot, often available at public libraries. Some publishers market their own books of tide data. You can buy watches that supply tide data. Computer programs are available which supply tide data. In coastal communities, tide charts are usually given away at bait and tackle shops as a service to customers.

Atmospheric conditions can strongly affect water movement during tides. High atmospheric pressure ("heavy" air) pushes down on the water surface suppressing high tides somewhat. Conversely, low pressure allows high tides to rise higher.

Friction caused by wind can strongly affects tides. Tidal range is least close to the Equator and increases as you move toward the poles. A funnel shaped bay (such as the Bay of Fundy) will exaggerate the tidal range more than will a wide flat.

Generally you find better fishing during spring tides than neap tides. On high tides water floods into areas that are usually dry, offering gamefish a feeding opportunity they don't often have. The fish quickly take advantage of the situation. As an example we can look at the way fish tail on top of the salt marshes from northwest Florida all the way up into the Carolinas on high spring tides. The high water floods areas which are normally dry, allowing reds to access the rich feeding grounds that are loaded with fiddler crabs. These tides give fly fishers a unique opportunity.

The same type of feeding situation occurs on rising tides anywhere there are oyster bars. Fish move up onto the bar to access food resources unavailable to the at low water.

When the current flows out as the tide drops, fish quickly move out of any areas where they might get stranded. They will often station themselves where a good current flow will bring food to them, somewhat like freshwater trout in a stream. Such places include creek mouths and "funnels" between oyster bars where water is forced to move through a break in the bars. Strong flows associated with spring tides often bring on heavier feeding. The reds can easily maneuver in the current, but the small fish and shrimp they feed on can't.

Finally, at low tide many of the places where reds might ordinarily swim are dry. They are forced and concentrated into deeper pockets and holes. If you can find such a location you find a gold mine. Capt. Terry Shaughnessy at the Hackberry Rod and Gun Club in Louisiana told me he and Mike Fine found such a place out in the marshes one winter day. They caught and released hundreds of reds, hooking up on every single cast for hours.

Since we have less water movement during neap tides, as a generalization fishing tends to not be as good then. The fish still behave the same way, it's just that the water isn't as helpful to either them or us.

This is an excerpt from Captain John A. Kumiski's new book Flyfishing for Redfish.