Abstract
The authors conducted swimming experiments in the field using ice goby (Leucopsarion petersi) in order to study its swimming ability and the relationship between tail beats and swimming speed. The experimental equipment used was a stamina tunnel, which was installed at a local dry riverbed. During one swimming experiment, the relationship between swimming speed and time with swimming distance was considered; in the other, the movement of the tail beats of the ice goby was analyzed using a high-speed camera and the relationships of the movement of the tail beats with their amplitude and the tail beat frequency with swimming speed were considered. As a result, a swimming-curve-formula defining the relationship between swimming speed and swimming time was obtained for ice goby, who have a body length from 4 to 5 cm. The ratio of the amplitude of tail beats to the total length of the ice goby was a constant 0.13, even with increases in frequency or swimming speed. The ice goby swam with a tail beat frequency of from 5.8 to 35.4 times per second, at from 2.7 to 27.8 times its own total body length per second, and a positive correlation was found between the swimming speed and the frequency. This allowed us to obtain an experimental formula defining the relationship between swimming speed and the frequency of tail beats.
