The Impact of Infrasound on Anxiety-Like Behaviour in Zebrafish

Abstract

Low frequency sound permeates the modern world, generated by both natural and human-made sources. Known as infrasound, these soundwaves have frequencies below 20 Hz, which is below the threshold for human hearing. The presence of infrasound in aquatic environments, generated by ships, underwater ocean turbines, and offshore wind power generation could be detrimental to fish population dynamics. Previous studies have shown that fish like salmon and eels will display avoidance to infrasound, making it an effective deterrent around the inlets of hydroelectric dams. Zebrafish have become a popular choice of research organism, due to their low cost and ease of care. The behaviour, development, physiology, and genetics of these fish have been studied extensively, making them ideal for understanding the mechanisms underlying observed behavioural effects. As prey animals they are extremely well suited for examining anxiety-like behaviours in tests like the open-field test and novel tank diving test. In this study, we examined the impact of 10 Hz and 15 Hz infrasound on zebrafish behaviour in the open-field test. Fish were habituated for 5 minutes in the arena, and subsequently exposed to infrasound (or control conditions) for 5 minutes. Video was recorded and analyzed for distance moved, time spent in zones, immobility and meandering. There were no significant differences between the treatment groups on any of the variables. The results suggest that zebrafish are not affected by infrasound at the frequencies and amplitudes tested.

Discipline: Psychology (Honours)

Faculty Mentor: Dr. Trevor Hamilton