CatchWindow fishing intelligence
Fishing the tide: why moving water matters
In tidal waters, many anglers plan their trips around the movement of the tide because moving water tends to concentrate both food and the fish that eat it. The periods when the current is starting, easing or changing direction are widely regarded as productive, and long stretches of still water are widely regarded as slow.
That is a rule of thumb built on generations of experience, not a law. It holds better in some places than in others, and plenty of fish are caught at supposedly wrong times. What follows sets out the reasoning so that it can be tested locally.
Why moving water matters
A tidal current works like a conveyor. It carries plankton, small crustaceans, worms and other food along with it, and small baitfish are moved about or follow the food. Predatory fish take advantage. Anglers commonly find that fish feed more readily when the current is bringing food to them than when the water is still.
Current also influences where fish position themselves. Swimming against a steady flow costs energy, so fish often hold where they can shelter from the main current while staying close to it: behind a rock or a bridge pile, along a drop-off, at the edge of a channel, or in the calmer water of an eddy. From there they can move out to take food passing in the faster water. Anglers call such features structure. When the water moves, the likely holding places become easier to guess, and that makes it easier to put a bait or lure in the right spot.
Rising water and falling water
The two halves of the tide change the shape of the fishing ground. A rising tide covers flats, marsh edges, rocky ledges and the upper beach, and fish commonly move up with it to feed over ground that was dry a few hours earlier. A falling tide drains those areas, and whatever was living or feeding there is drawn back towards deeper water. Creek mouths, channel edges and the outflows of lagoons and estuaries can fish well on the ebb for that reason: the food is funnelled through a small area.
Why the turn of the tide gets so much attention
Many anglers favour the hour or two either side of high or low water, or more precisely either side of the turn of the current. Several reasons are usually given.
As the flow starts up after slack water, food begins to move again and fish that were inactive often begin to feed.
In places with strong currents, the middle of the tide can be too fast to fish effectively. Baits will not stay on the bottom and lures sweep past too quickly, so the slower water near the turn is the practical window.
Slack water itself is often reported as a lull. With nothing moving, food is not being delivered and fish may scatter or stop feeding.
The turn of the current is not always at the time of high or low water shown in a tide table. In channels, inlets and estuaries it can come considerably earlier or later, as the article on slack water explains. Where a current prediction exists, it is the better guide to when the water will actually be moving.
How it varies with place and species
The right stage of tide is a local question. In an area with weak tidal flow, the strongest part of the tide may be the only time there is enough movement to stir things up. In a fast tidal pass, the reverse is true. On a surf beach, the stage of tide decides which troughs and sandbars hold enough water. On a shallow flat, it decides whether fish can reach the ground at all.
The fortnightly cycle matters as well. Spring tides bring stronger currents and cover and uncover more ground, while neap tides are gentler. Species differ too. Fish that ambush prey around structure, fish that roam open water after schools of bait and fish that forage along the bottom do not all respond to current in the same way.
Tide is also only one influence among several. Light level, water temperature, water clarity, wind, recent weather and the time of year all play a part, and they interact. Many anglers rate a favourable tide at dawn or dusk above the same tide in the middle of the day.
An honest caveat
All of the above is accumulated experience. It describes tendencies that many anglers have observed, and the reasoning behind it is sensible, but it is not a guarantee and it is not the same in every fishery. Good tides produce blank days, and poor tides occasionally produce memorable ones.
The most reliable way to use the tide is to keep notes. For each trip to a given spot, record the stage of tide, the direction and strength of the current, the time of day, the conditions and the result. After a season or two, patterns specific to that place tend to emerge, and they are worth more than any general rule.
Planning a trip around the tide
Start from the tide and current predictions for the nearest suitable station, pick out the periods when the water will be moving but fishable, and see how they line up with dawn, dusk and the weather. CatchWindow location pages bring together tide predictions, wind and weather forecasts, solunar periods and activity scores from 0 to 10, with a week-ahead view for comparing days. Treat a score as a summary of conditions, not a promise of fish.
Whatever the fishing prospects, a rising tide can cut off rocks, sandbars and the foot of cliffs, and strong currents are hazardous to small boats and to anyone wading. Check official tide tables and the marine forecast before going, and know the way back to safe ground before the water comes up.