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Quite often, and sometimes unconsciously, we identify the elements that break up the monotony of a body of water or a river as a favorable spot for fishing. This is an excellent analysis, even if we don't necessarily know why. Let's try to understand it a little better...
Changes in bathymetry
Bathymetry is the science of measuring depths. In other words, it is a representation of the underwater relief. Indeed, variations in depth and any changes in relief are excellent areas to prospect, as they may harbor fish.
Big breaks in the background are obviously very good, but smaller variations can also be productive.
In fact, changes in depth help to fix food and, by extension, life. Combined with currents, they modify the flow of water and thus "channel" the supply of food. But they also create cushioning zones where sediments and organisms accumulate.
Last but not least, bottom breaks provide excellent shelter from the current for resting, as well as perfect lookout points for predators.
Substrate changes
Changes in substrate, and even more so the edges of these, are excellent spots. Once again, it allows predators to lie in wait, notably through mimicry. But it also multiplies and diversifies the food available in the area. At the edges of substrates, for example, we can find totally different organisms and prey, and consequently a greater diversity of feeding fish species.
Encounters and current edges
The current is a vital element for fishing, as it carries food. But not all water veins are created equal, nor are they all nourishing. However, when several water veins meet, they multiply the supply of food and create zones of turbulence, counter-current and rest where organisms accumulate and fish can effortlessly stay in the immediate vicinity of the feeder vein: the sofa near the fridge!
Bank relief
Changes in bank relief have exactly the same effects as changes in depth. But instead of being vertical, they are horizontal. Thus, drops, peaks and indentations create current deviations and cushioning, and establish local life and thus a food chain. In addition, the relief of the bank is a geographical landmark that fish use and follow to get from point A to point B. Carp anglers know this all too well. Carp anglers are well aware of this, and analyze the geography of the water to determine possible passage zones and where to place their lines.
While it's clear that not all break zones will be created equal, and perhaps not all will be successful, it's equally clear that a place that combines changes in relief, currents and substrates will be a priority to visit.
