Turbidity and predation risk: behavioural responses of a freshwater minnow. (April 2022)

• Record Type: Journal Article
• Authors: Leris, Ioannis; Koepchen-Thomä, Lea; Smeti, Evangelia; Kalogianni, Eleni
• Is Part Of: Animal behaviour. Volume 186(2022)
• Page Start: 1
• Page End: 9
• Publication Date: 2022-04
• Subjects: activity -- antipredator behaviour -- boldness -- cyprinid -- exploration -- periphery -- predator response -- shelter -- suspended sediment -- thigmotaxis; Animal behavior -- Periodicals; 591.5
• DOI: 10.1016/j.anbehav.2022.01.014
• Languages: English
• ISSNs: 0003-3472

Abstract

Abstract : High water turbidity, through its multifold influences on aquatic fauna, is considered a major cause of ecological concern. Here we examined the effects of elevated turbidity on the behaviour of a small cyprinid fish, the Stymphalia minnow, Pelasgus stymphalicus, using a combination of the well-established emergence, open field and predator response tests. Subjects from the two treatments differed in the way they emerged from an artificial refuge, with the turbidity-exposed fish being more hesitant. Moreover, these fish were also less active, had a lower propensity to explore and spent less time in the open centre of the test arena, compared to subjects tested in clear water. However, there was no effect of turbidity on the time fish spent immobile. Fish in both treatments responded strongly to a simulated predator attack from above. Turbidity decreased the time fish spent in the centre, the predator simulation decreased time spent immobile and both factors contributed to a decrease in activity, but without significant interaction effects. We discuss how turbidity may increase the perceived predation risk of these prey fish in our test conditions even in the absence of predator cues, as well as the implications of our findings for ecosystem management policy and conservation efforts targeting threatened freshwater fish species. Highlights: Minnows underwent emergence/open field/predator response tests. Fish exposed to turbidity were more hesitant to exit a refuge than control fish. Turbidity-exposed subjects were less active and less exploratory in the novel arena. A simulated predator attack decreased activity and increased immobility in all fish. Turbidity decreased the time fish spent in the centre of the arena in both tests.