Aversion response of fishes to ultrasonic sound, near ultraviolet radiation and artificial magnetic field.

2006 Fiscal Year Final Research Report Summary

• Project/Area Number: 17580167
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: General fisheries
• Research Institution: Kagoshima University
• Principal Investigator: KAWAMURA Gunzo Kagoshima University, Faculty of Fisheries, Professor, 水産学部, 教授 (30041718)
• Co-Investigator(Kenkyū-buntansha): NISHI Takaaki Kagoshima University, Faculty of Fisheries, Assistant professor, 水産学部, 講師 (30237656)
• Project Period (FY): 2005 – 2006
• Keywords: Physical stimuli / Ultrasonic sound / Near ultraviolet radiation / Artificial magnetic field / Aversion response / Retina / Visual

Research Abstract

1) Rabbitfish Siganus fuscescens, Japanese parrotfish Calotomus japonicus and large-tailed drummer Kyphosus lembus showed no behavioral changes and did not stop foraging on the algae during the exposure to 90 kHz and 200 kHz sounds from fish finders in a tank and a fish cage. It was concluded, therefore, that the ultrasonic sounds used were not aversion stimuli for the fishes.
2) Aversive effect of flickered ultraviolet radiation (UV) was examined on 8 fish species in a tank, a fish cage and rivers. The ultraviolet was radiated from light emitting diodes (A.max = 386 nm) arranged in a water proofed transparent tube. The radiation intensity was varied from 0 to 39.61 μW/cm^2/nm and flickering frequency was varied from 1 to 20 Hz. Japanese dace Tribolodn hakonensis and spotted mackerel Scomber australasicus showed typical aversion responses. The mature migrant chum salmon Oncorhynchus keta did not respond to the flickered UV at all in a tank. Pale chub Zacco platypus, ayu Plecoglossus eltivelis, largemouth bass Macropterus salmoides and horse mackerel Trachurus japonicus exhibited a weak aversion response to the UV. The juvenile bluegill Lepomis macrochirus showed a remarkable positive phototaxis to a flickering white light in a tank, but they were not attracted to the flickering UV, green light and red light in a lake.
3) Japanese killifish Oryzias latipes and Japanese eel Anguilla japonica were exposed to a strong artificial magnetic field, 313 times and 801 times the geomagnetic field respectively. Japanese killifish did no avoid the artificial magnetic field in a tank. Japanese eel escaped from a shelter placed when the artificial magnetic field was given in a tank and lost the magnetosensitivity after the exposure for 45 minutes.
It was concluded that the flickering UV and the strong artificial magnetic field were aversive stimuli for fishes and would be of a considerable promise for fish behavior control.