Fish with red fluorescent eyes forage more efficiently under dim, blue-green light conditions

BMC Ecology

Research Article

Ulrike Katharina Harant¹  Nicolaas Karel Michiels¹ 

[1] Department of Animal Evolutionary Ecology, Institution for Evolution and Ecology, University of Tuebingen, Auf der Morgenstelle 28, 72076, Tuebingen, Germany;Department of Biology, Faculty of Science, University of Tuebingen, Auf der Morgenstelle 28, 72076, Tuebingen, Germany;

关键词: Foraging success;    Visual ecology;    Tripterygion delaisi;   

DOI  :  10.1186/s12898-017-0127-y

 received in 2016-12-10, accepted in 2017-04-05,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundNatural red fluorescence is particularly conspicuous in the eyes of some small, benthic, predatory fishes. Fluorescence also increases in relative efficiency with increasing depth, which has generated speculation about its possible function as a “light organ” to detect cryptic organisms under bluish light. Here we investigate whether foraging success is improved under ambient conditions that make red fluorescence stand out more, using the triplefin Tripterygion delaisi as a model system. We repeatedly presented 10 copepods to individual fish (n = 40) kept under a narrow blue-green spectrum and compared their performance with that under a broad spectrum with the same overall brightness. The experiment was repeated for two levels of brightness, a shaded one representing 0.4% of the light present at the surface and a heavily shaded one with about 0.01% of the surface brightness.ResultsFish were 7% more successful at catching copepods under the narrow, fluorescence-friendly spectrum than under the broad spectrum. However, this effect was significant under the heavily shaded light treatment only.ConclusionsThis outcome corroborates previous predictions that fluorescence may be an adaptation to blue-green, heavily shaded environments, which coincides with the opportunistic biology of this species that lives in the transition zone between exposed and heavily shaded microhabitats.

【 授权许可】

CC BY   
© The Author(s) 2017