As clear as mud: Turbidity induces behavioral changes in the African cichlid Pseudocrenilabrus multicolor

Abstract

Aquatic biodiversity is being lost at an unprecedented rate. One factor driving this loss is increased turbidity, an environmental stressor that can impose behavioral, morphological, and/or physiological costs on fishes. Here we describe the behavioral response of a widespread African cichlid, Pseudocrenilabrus multicolor victoriae, to turbidity. We used a split-brood rearing design to test if F1 offspring reared in turbid water, originating from river (turbid) and swamp (clear) populations, behave differently than full-sibs reared in clear water. We examined two facets of behavior: (1) behaviors of fish in full sib groups, including activity level and social dynamics collected during the rearing period; and (2) male aggressive behavior directed at potential male competitors after fish had reached maturity; this was done in an experimental set-up independent of the rearing aquaria. Regardless of population of origin, fish reared in turbid water were marginally less active and performed fewer social behaviors than those reared in clear water. On the other hand, when tested against a competitor in turbid water, males performed more aggressive behaviors, regardless of population of origin or rearing environment. Our results suggest a plastic behavioral response to turbidity that may allow P. multicolor to persist over a range of turbidity levels in nature by decreasing activity and general social behaviors and intensifying reproductive behaviors to ensure reproductive success.

Developmental plasticity in vision and behavior may help guppies overcome increased turbidity

“…Our study is one of the first to show effects of development in turbid water on adult fish behavior (also see Gray et al 2012): although most previous studies document either no change (Ranåker et al 2012) or a decrease (Leahy et al 2011;Borner et al 2015) in baseline activity for adult fish Activity before and after the introduction of a predator cue to assay tanks for both treatments. Grey lines connect multiple trials for individuals.…”

Turbidity affects social dynamics in Trinidadian guppies

“…In the presence of predator cues, pike larvae (Esox lucius) hid within the vegetation less and exploited the open water more when under turbid conditions than when under clear water conditions (Lehtiniemi et al 2005). However, African cichlid showed a marginally significant decrease in activity in turbid water when fish were reared in turbidity (Gray et al 2012).…”

Algal Turbidity Hampers Ornament Perception, but Not Expression, in a Sex‐Role‐Reversed Pipefish

“…; Gray et al. ). Although we did not find that turbidity had an effect on the development of female ornaments, it did affect signal perception through hampered male mate choice for the larger and more ornamented female, which hence is in line with previous experiments and also follows our prediction.…”