The Role of Visual Cues in Prey Selection in Three‐spined Sticklebacks (Gasterosteus aculeatus)

Abstract

AbstractIn order to determine the proximate cues responsible for prey selection by sticklebacks, subjects were given a series of choices between pairs of prey items differing in the visual characteristics that differentiate natural prey species. When only one stimulus‐dimension was varied, the sticklebacks showed significant preference for, in decreasing order for each stimulus dimension, red and pale over dark colour, relatively fast over slow movement, straight and rectangular over globular shape and larger over smaller size. In contrast, the way in which the prey moved did not influence prey choice. When two stimulus‐dimensions were varied simultaneously, colour (if red) was shown to be a more important cue than movement, followed by shape, and then by size. When red colour was replaced by pale colour, a different preference order was found, with movement becoming more important than colour, followed by shape and then by size. These results are discussed in the light of the existing literature of prey selection in fish.