Fish avoid visually noisy environments where prey targeting is reduced

The environment contains different forms of ecological no­­­ise that can reduce the ability of animals to detect information. Here we ask whether animals adapt their behaviour to either exploit or avoid areas of their environment with increased dynamic visual noise. Three-spined sticklebacks (Gasterosteus aculeatus) were immersed into environments with a simulated form of naturally occurring visual noise – moving light bands that form on underwater substrates caused by the refraction of light through surface waves. We tested whether this form of visual noise affected fish’s habitat selection, movements, and prey-targeting behaviour. Fish avoided areas of the environment with increased visual noise, and achieved this by increasing their activity as a function of the locally perceived noise level. Fish were less likely to respond to virtual prey in environments with increased visual noise, highlighting a potential impact that visual noise has on their perceptual abilities. Fish did not increase or decrease their refuge use in environments with increased visual noise, providing no evidence that visual noise either increased exploratory, or, risk aversive behaviour. Our results indicate that animals can use simple behavioural strategies to avoid visually noisy environments, thereby mitigating the impacts these environments appear to have on their perceptual abilities.   

Usage Notes

Sheet 1 labelled 'Choice' - contains the data from the choice experiment. Each row in the data gives one choice (out of 15) that the fish was given in each of 48 trials. Column 1 gives the trial number, column 2 is the day of the trial out of 10, column 3 is the noise level on the left of the arena, column 4 is the noise level on the right of the arena, column 5 is the difference in noise between these two sides (so a noise level of 3 on the left and a noise of 2 on the right would give a difference of 1). Column 6 shows which is the noisier side of the arena with '1' meaning the left is the noisier side and '0' meaning the right side is the noisier side. Column 7 is which of the 6 playbacks was used for that trial, column 8 is the temperature in celsius of the arena at the start of the trial, column 9 gives the time the trial was started given in hours after 6am, column 10 is the order of the trial within the current day, column 11 is the number of choice within the trial (between 1 and 15), column 12 is the noise on the noisiest side of the arena, column 13 is the noise on the slower side of the arena (information taken from columns 3,4 and 6). Column 14 is the fish's speed when on the fast side of the arena for that choice and column 15 is the fish's speed when on the slow side of the arena for that choice. Column 16 is the proportion of time that fish spent stationary when on the more noisy side of the arena for that choice and column 17 is the proportion of time the fish spent stationary when on the less noisy side of the arena. Finally column 18 is the proportion of time the fish spent on the noisier side and column 19 is the proportion of time the fish spent on the less noisy side of the arena. Sheet 2 labelled 'Refuge' - contains the data from the refuge experiment. The data is showing the amount of time in seconds that the fish spent in a refuge for each of six levels of noise in each of 48 trials. Column 1 gives the trial number, column 2 gives the number of seconds (with a maximum of 320) that the fish spent in the shelter for each noise level within the trial, column 3 gives the order that the noise level was presented within the trial (between 1 and 6), column 4 is the noise level the fish was currently experiencing at that time in the trial (between 1 and 6 with 6 being the highest level of noise), column 5 is which of the 6 playbacks was used for that trial, column 6 shows the day of the trial (between 1 and 6), column 7 gives the time the trial was started given in hours after 6am, column 8 is the order the trial was done in the day (between 1 and 8) and column 9 is the is the temperature of the water in the test arena when the trial was started. Sheet 3 labelled 'Virtual Prey' - contains the data from the virtual prey experiment. Each row in the data shows the number of detections for each of 6 levels of noise in each of 108 trials. Column 1 is the level of noise the fish was currently experiencing at that time in the trial (between 1 and 6 with 6 being the highest level of noise), column 2 gives the number of detections for that level of noise in the trial, column 3 gives the trial number out of 115, column 4 gives the day of the trial (between 1 and 20), column 5 is the time the trial was started given in hours after 6am,  column 6 is the temperature of the water in the test arena when the trial was started, column 7 is which of the 6 playbacks was used for that trial, column 8 gives the order the trial was done in the day and column 9 gives the time of the noise level within the trial (between 1 and 6).