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Confused about tides? You’re not alone, so are most other anglers!

Considering it’s the tides that govern movements of fish, fishermen need to read a tide table and be able to calculate high and low water times. The health of the sea and all its creatures depends on the ceaseless movement of water. Moving water disperses pollutants, carries nutrients to phytoplankton, the tiny floating plants that are the base of the ocean's food chain, and concentrates bait, which then attracts larger fish. In simple terms baitfish will feed on plankton which can not swim and are moved about by currents. Areas where the plankton are concentrated will attract baitfish and they in turn will attract the gamefish who feed on the baitfish. Each is following its source of food, but the distribution of the plankton (and some small types of baitfish), which can not swim are controlled by the currents. Strong currents can sometimes overwhelm the swimming ability of baitfish and concentrate them, even if there are no plankton for them to feed on. This strong association of plankton, baitfish and gamefish with currents frequently explains why fishing will slow down or even stop when the current ceases. During slack water there is no current to concentrate either the plankton or baitfish, and they will be dispersed. In general, the stronger the current the more the possibility of concentration and disorientation of baitfish. Thus the increased opportunity to catch the larger fish who feed on the baitfish. Most saltwater fish are wanderers: they follow the currents of the food that is carried on the currents. An area with moving water is generally a good place to fish; areas without moving water usually provide poor fishing.  Tides are especially important for beach fishing. Their effects will vary depending on the character of the beach, especially its slope, the tidal range, and weather and sea conditions such as wave height and direction of the wind. The gentler the slope of the beach or the greater the tidal range, the larger the part of the beach that is exposed and then covered by the tide. Some structures or favorable areas are only reachable at low tide. A smart beach angler will explore a fishing area at low tide to find the location of pools or other structures that will be covered, but fishable at high tide. This technique should be repeated following any strong storms or period of onshore winds, which can change the character of the bottom. A rising tide will increase water depth and frequently carry in bait and larger fish from offshore. The rising tide will also create tranquil areas over depressions, as well as turbulent areas where the tidal current is constricted. The latter can also happen with a falling tide. The two hours before and after the high tide are frequently the best times for fishing along a beach. The time just after slack water may also be productive since the start of water motion frequently initiates feeding activity. Remember, slack water does not always correspond with times of high and low tide. If you have good luck with a specific tide, remember that similar tidal conditions will be occur 24 hours and 50 minutes later. The principle generally works, but remember some fish prefer to eat at dawn or dusk regardless of the tide. Once you start paying attention to the phases of the moon you should be able to estimate the relative strength of the tide. If you fish in an area where the tides are of the mixed or semidiurnal variety note which of the two daily high tides is the highest. Fishing the stronger (higher) high tide when it occurs at dawn or dusk often yields especially good results.

WHY AND HOW DO THE TIDES RISE AND FALL EACH DAY?

It’s the moon and sun that create the tides! Think of the sun and moon as being magnets. Their individual gravitational pull works like a true magnet does on metal, it pulls the water towards them. Look at the Atlantic Ocean as being a large pudding basin filled with water. As the Earth rotates the moon and sun’s gravitational pull drag water over to one side of the basin like a single big wave. As the Earth continues to rotate, the gravitational pull is slowly transferred to the other side of the basin pulling the water back in the opposite direction. The big spring tides are caused again by the sun and moons gravitational pull. When the moon is in it’s full and new moon phases it lines up roughly between the earth and the distant sun. The two gravitational pulls are then working together and have a greater magnetic influence on the water pulling a greater amount towards them resulting in a bigger Atlantic wave or bulge. The biggest spring tides always fall a couple of days after both the new and full moons. The smallest neap tides come two days after the half moon phases. For seven days after each new and full moon, the moon travels outside this line at an increasing right angle between the Earth and Sun which reduces it’s gravitational influence and decreasing the amount of wave or bulge pulled eastwards across the Atlantic. On the seventh day, this is when the moon is in it’s with the moon at a sharp angle to the sun, the tide will ebb and flood the least distance over the beach. From then on, the tides increase in size as the moon comes back further in line with the sun each day. There is an annual cycle as well as this monthly cycle. The biggest tides during the year occur around the 21st March and again on 21st September when the moon is directly between us and the sun and having their combined greatest magnetic force. The smaller spring tides happen in June and December when the moon and sun are working at a less sympathetic angle to each other with a reduced gravitational pull.

WHICH FLOWS FASTER, THE FLOOD OR EBB TIDE?

The incoming tide floods for roughly 5 and a half hours and the ebb tide for six and half hours. The same volume of water has to move on both flood and ebb, but because the flood tide travels from low to high in less time this is generally when the tide is strongest. Having said that, some local conditions such as protruding headlands, estuary channels, bottlenecks between islands etc, can all cause the ebb tide to flow stronger than a flood tide. If you break the tide down into three segments of roughly two hours to compare how much water is flowing during each part of the tide, you’ll find that during the first segment the tide will rise 25% of it’s height. In the second segment the tide rises 50% of it’s height, and obviously rises a further 25% in the final period. On shallow open beaches, you’ll notice that on neaps the flood tide pushes you back along the sand slowly, but on big spring tides, you’ll be moving your tackle back every few minutes. The slack water periods are also affected by the size of the tide. The actual low water period of a small neap tide sees no noticeable in or out tidal movement for maybe well over an hour. But on the biggest spring tides, actual slack water hardly occurs at all with the water changing direction and showing movement of the new flood all within 15 minutes, or so. It’s the same at high water.

HOW ACCURATE ARE TIME AND HEIGHTS IN TIDE TABLES?

Considering that you’re trying to predict the speed and directional movement of billions of gallons of water, this in turn influenced by outside forces like wind strength and direction, and even the effects of weather systems maybe a thousand miles away, then predicted accuracy is excellent. The heights are within 5% of predicted levels on average, with the peak high tide time accurate on average to within 5 minutes, at most 15 minutes.

If you need information, or wish to book an Offshore Charter, please call us on 321-724-1440, or email::captstovall@whiteysonline.com