Background choice as an anti-predator strategy: the roles of background matching and visual complexity in the habitat choice of the least killifish

A1 Journal article (refereed)

Internal Authors/Editors

Publication Details

List of Authors: Kjernsmo K, Merilaita S
Publisher: The Royal Society Publishing
Publication year: 2012
Journal: Proceedings of the Royal Society B: Biological Sciences
Journal acronym: P ROY SOC B-BIOL SCI
Volume number: 279
Issue number: 1745
Start page: 4192
End page: 4198
Number of pages: 7
ISSN: 0962-8452
eISSN: 1471-2954


Because background matching improves concealment, prey animals have traditionally been expected to prefer parts of the habitat that match their visual appearance. However, empirical support for this is scarce. Moreover, this idea has recently been challenged by an alternative hypothesis: visual complexity of the background impedes prey detection, and hence prey could instead prefer complex parts of the habitat. We used the least killifish to test, with and without predation threat, for the importance of the visual similarity between the fish and the background, and the level of visual complexity of the background. We observed their choice between backgrounds patterned with elements based on the longitudinal black stripe of the fish. Predation risk was important under some circumstances, and induced a preference for a background of matching horizontal stripes compared with mismatching vertical stripes. Interestingly, females under predation threat showed a preference for a complex background of randomly oriented and overlapping stripes compared with matching stripes, whereas males did not discriminate between these two. Additionally, males showed a preference for matching stripes compared with complex shapes, whereas females did not discriminate between these backgrounds. We conclude that matching is important in the choice for safe habitat, but some aspects of visual complexity may override or act together with background matching.


background matching, complexity, crypsis, habitat choice, predation, prey coloration

Last updated on 2019-15-09 at 06:40