A sensory approach to turbidity: how sources and levels shape aquatic light environments and fish visual ecology

Journal article

Turbidity is a ubiquitous property of aquatic environments likely impacting the appearance of visual cues that inform critical behaviours for many fish species. Taking a sensory perception approach is key to understand how turbidity affects fish behaviour: specifically, we must identify how different turbidity sources modify the visual environment and constrain what fish can see. In this study, we quantified how four common turbidity sources (algae, bentonite, calcium carbonate, and kaolin) altered the ambient light spectrum across a range of turbidity levels. We also quantified effects on key visual signal properties, including luminance, hue, and chroma, and evaluated the practical suitability of each turbidity source for laboratory use by measuring settling rate, pH, and carbonate hardness (KH). Both turbidity source and level influenced the ambient light spectrum. As turbidity increased, calcium carbonate and kaolin raised luminance, algae reduced it and caused the largest change in chroma, and bentonite the greatest hue shift. Our findings underscore the need for a sensory perception framework in turbidity research, as variation in turbidity type and light conditions can reshape the transmission and perception of visual signals in distinct, species-specific ways with important ecological and behavioural implications.

Authors: Garcia, A; Sibeaux, A; Burt De Perera, T; Newport, C

• Publication status: Accepted
• Peer review status: Peer reviewed
• Publisher: The Royal Society
• Journal: Royal Society Open Science
• Acceptance date: 2026-05-08
• EISSN: 2054-5703
• Language: English
• Keywords: algae; behaviour; sensory pollution; suspended sediment; teleost; vision