Rattling lures are always a hot topic among anglers. Some people believe rattles help and others avoid them, most however don’t pay much attention to it. This question is surrounded by all sorts of myths and human projections on fish and their behavior. We don’t have all the answers but we’ll be careful to sort out assumptions from known facts.
Sound travels much better in water than in the air, at the speed of about 1.5 kilometers (1 mile) per second, and it travels much further away. Whales can communicate over hundreds of kilometers and there’s no doubt fish can hear noises from very far away. The first piece of advice I would give is to go underwater and listen; to ambient background noise, to your trolling motor and sonar, and to your favorite lures.
But that will give you only a partial idea of what fish hear. We do not share the same acoustic perception abilities as fish. In fact, our ear is to a large extent superior to theirs. For example, they are not capable of earing multiple frequencies harmonics as we do. But I have never heard of a lure with a philharmonic orchestra inside, so it’s not really relevant!
As far as I know, the question of the fish’s ability to locate the source of a sound is still open. We perceive sound direction by measuring the time lag between when a sound strikes one hear versus the other. It’s very effective because our head is fairly wide and sound is slow in the air. But a fish head is small and the sound is too fast in the water.
And yet fish seem to be able to find the source of a sound. How accurate is this capacity is hard to tell, it most likely work in conjunction with the eyes for pinpointing the exact origin of a sound. To summarize: fish can hear sound from a long way away, they can’t discriminate it is precise details, and can only approximately tell where it comes from.
Every movement displaces water and therefore creates sound. Therefore, every lure is noisy. The idea of silent lure is fiction, unless immobile. But the range of sound is huge. A stick worm very slowly crawled at mid-depth is very nearly silent. But most lures create a good amount of noise: spinnerbait, swimbaits soft and hard, topwater, chatterbait, and so on are ALL noisy.
This is where the rubber meets the road, what about rattling lures such as crankbaits and jerkbaits? Can fish become aware that these sounds are associated with danger? The short answer is yes, but near as much as most people think. First of all the learning ability of fish is way lower than us, otherwise, they would have schools and universities. Well, they have schools but let’s not confuse the issue!
Also, real fish food is noisy too, crawfish and baitfish are not silent. If they stop eating food that makes noise, they die. And as we stated before, their ability to discriminate noises is much lower than ours. But what they can do is differentiate rhythms, and nothing alive in the water makes a regular mechanical noise. It’s a more random irregular noise pattern. So we should be conscious to break the rhythm of our lures. It’s very visually and acoustically important, because that’s how nature behaves.
So when to use a rattling lure? I see it essentially like the color selection. I want the lure to be found, but not have an overbearing presence. In very clear and calm water, and if I know the lure is close to the fish, I don’t think it adds anything and I would avoid rattling lure. But if for example, I’m fishing around grass, even in clear water the lure will be hidden, a solid sound signature will help fish locate my lure.
This is an entirely different topic because by nature the sound signature of these lures will be random and irregular. In low visibility conditions, it will definitely help increase the lure detection footprint and allow predators to find the prey. Some jigs and soft plastic lures come stock with a rattle and that’s a big plus for me when shopping for lures. You can insert a glass rattle inside a soft bait or add a glass bead after the sinker on a Texas rig.
Rattling lures will continue to be surrounded by a cloud of mystery. It’s impossible to fully grasp how fish perceive and react to sound and noisy lures. Keep an open mind and let the fish tell you what to do.