Report of the Study Group on Fish Avoidance to Research Vessels (SGFARV)

The Study Group on Fish avoidance to Research Vessels (SGFARV) was created to answer one major question: how important is the avoidance reaction of fish to a research vessel? This question was originated by divergent observations on avoidance reaction to research vessels, and especially to vessels fulfilling the noise limited conditions recommended by the Cooperative Research Report 209, compared to “noisy” vessels.After a general overview of the problem “Fish avoidance to research vessels: an old question not yet elucidated” (Julia Parrish and François Gerlotto), five presentations were given during the meeting, on "Fish Escorting Vessels: attraction, density dependence or avoidance reactions" (Mariano Gutierrez), “Herring behaviour in response to approaching vessels” (Nils Olav Handegard), “Comparing noisy and sound-reduced vessels” (Chris Wilson), “Tank experiments on effect of vessel noise” (Bjarne Stage, Bo Lundgren and Karl-Johan Staehr).The definition of sound characteristics was discussed. Sound spectrum graphs of high frequency resolution can be used to characterize emitted sound from all vessels. From historical reasons most recorded emitted sound from vessels has been analysed within third octaves bands. From sound reception and related behaviour in living organisms we know that both tonal and broadband components as well as the critical bandwidth play important roles in sound reception. Which of these components is of greater importance in sound reception in fish as well as their impact on behaviour alterations must be elucidated and explained.