As reported in the previous post, common perch, Perca fluviatilis, do not respond to sounds of the rattling wobblers. In this post, we will show that perch ignore also sounds of the glass rattles mounted in the soft plastic lures.

Predatory fish do not respond to sounds of rattling wobblers

In these field experiments, noisy and quiet 5 cm Bobby Garland Baby Shads, Cajin Cricket color (Fig.1), were compared. One half of lures, marked BSN, were equipped with the eye-like double flanged glass rattles. They were made of glass tubes of 3 mm diameter, with 1 steel ball (like products of Rattle Arsenal Co.). In the other half of lures, marked BSQ, balls in the rattles were made of the silent graphite. Both flanges of the rattle, mounted perpendicularly into the Bobby Garland Baby Shads’ body, looked like the real eyes.

Figure 1. Bobby Garland Baby Shad (shown without an inserted eye-like glass rattle)

For lure presentations, typical drop shot rigs, with the 30 cm distance from lures to 10 gr standard bell like lead sinkers, were used. The two rigs fell into the two holes (10 cm diameter) drilled (at the distance of 20 cm between holes’ centers) in the ice. The depth at the fishing localities (the region of Kyiv, Dniepro river) was about 3-5 m, usually with weak underwater flows. Sinkers fell to the bottom, then lures were alternately jolted by an ice rod tip: 2 jolts per sec with an amplitude of 1-2 cm. Jolting (without lifting the sinkers) lasted 10 sec for one lure then 10 sec for the other lure, with some minute rest between one minute alternate joggles.

In the tests, perch ignored unactive lures choosing noisy or quiet jolted lures. Therefore, we used the sign test for statistical processing of the field findings. In total, 31 perch were iced during 1 day: 17 on BSN and 14 on BSQ. According to the sign test, these differences are statistically unreliable. In other words, perch ignored sounds of the glass rattles mounted in the soft plastic lures.

The same results, that is the absence of preference, have been obtained in the other 3 sessions with the foregoing lures (but with the two new colors: Pearl & White as well as Crystal) carried out in similar fishing conditions. Importantly, acoustic noises under the ice are much less than in the summer (due to the absence of waves, rain and acoustic activity of many animals: Protasov, 1965).

There are several reasons why perch ignore sounds of the glass rattles. For more information, please see the post mentioned above.

Basic References

Protasov V.R. 1965. The bioacoustics of fishes. Moscow, Science