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Why would a big lure favour a big fish?
According to theory, big fish often feed on large prey, which makes the idea of a large lure quite logical: a "big bite" would attract predators capable of gobbling up large prey. Presenting a "big bite" could therefore attract the finest specimens.
Another advantage of the big lure: its volume and silhouette displace a large quantity of water and generate fairly intense vibrations. This sensory stimulus can be detected by the lateral line of the fish, which can be an advantage.
What's more, using an imposing lure often has the effect of "filtering" the fish: subjects that are too small, unable to ingest such a mass, will be less inclined to bite, which mechanically increases the proportion of catches of a more correct calibre.
Finally, big fish are generally older and more economical in their movements. As such, a bulky lure representing a "profitable" energy meal may arouse their interest more than a small one.
Why isn't this always true?
Although "big lure = big fish" makes sense in certain circumstances, the reality of fishing shows that it doesn't always work, and several factors can render the strategy ineffective or even counter-productive.
The main thing to consider is the size of the prey hunted by the fish present in the area. If the fish are hunting small prey, for example 5 cm, it makes little sense to offer them a 180 mm shad. This disproportion could be counter-productive and alert the fish to the artifice in front of them.
Neither big nor small, just the right size to fitâeuros¯!
In practice, the best advice I can give is to adapt your lure strategy to the reality of the moment.
If you're looking for a big fish in a favourable environment, i.e. rich biotope, possible presence of big predators, voluminous natural prey, then don't hesitate to use a big lure.
On the other hand, if the environment or fish population doesn't justify it, opt for a smaller or intermediate lure: the frequency of hits, and sometimes the surprise of a beautiful specimen, can then become your ally.
Vary approaches by alternating lure sizes and shapes
A "standard" lure to test, then a bigger one if nothing bites, or vice versa.
Last but not least, give priority not only to size, but also to volume, behavior and adaptation: swimming, vibrations, discretion... These are the factors that can make all the difference.
What's more, big lures stir up a lot of water and are often noisy or highly visible.
Under certain conditions (clear, shallow or calm water, precise positions) this agitation caused by a large lure will be anything but effective: it can scare off fish, both large and small.
In such situations, a more discreet, more natural lure will often produce better results.
