Data for "Effects of reduced visibility on fish behavior: Low light is not equivalent to suspended sediments"

Description

Abstract (English)

Human development has caused soil erosion and increased particulate levels throughout waterways, increasing turbidity levels and impairing aquatic visibility. Heightened turbidity levels then change fish behavior by influencing antipredator responses, social preferences, foraging and other behaviors. Studying the impacts of turbidity is unfortunately logistically challenging because in the laboratory particulates tend to settle quickly, so some researchers have turned to altering the lighting environment to mimic the impacts of turbidity. Here, we compared zebrafish social and movement behavior in kaolin clay, a common experimental turbidity-causing agent, versus black pond dye, a potential easier-to-use alternative to clay, and evaluated if their fluctuation over time alter their impacts. Overall, we found that the effects of black pond dye differed from the effects of kaolin clay. Fish moved more in black pond dye then in kaolin clay, being on average 1.3x faster and 1.1x more active, with fluctuating visibility exaggerating this effect. Fish also showed more pursuit behaviors in clay than dye, performing 1.2x more aggressive contacts, 2.3x more chases, and 2.2x more follows. Our results suggest that black pond dye is not a sufficient substitute for turbidity and, further, that fluctuating visibility levels affect how fish respond to turbid conditions.