Affordable Access

Access to the full text

Water clarity affects collective behavior in two cyprinid fishes

  • Michael, Sabrina C. J.1, 2
  • Patman, Jon1, 3
  • Lutnesky, Marvin M. F.1, 4
  • 1 Eastern New Mexico University, Portales, NM, USA , Portales (United States)
  • 2 University of Missouri, 105 Tucker Hall, Columbia, MO, 65211-7400, USA , Columbia (United States)
  • 3 University of Missouri, 201 Engineering Building, West Columbia, MO, 65211-7400, USA , West Columbia (United States)
  • 4 Texas A&M University – San Antonio, One University Way, San Antonio, TX, 78224, USA , San Antonio (United States)
Published Article
Behavioral Ecology and Sociobiology
Springer Berlin Heidelberg
Publication Date
Aug 12, 2021
DOI: 10.1007/s00265-021-03060-x
Springer Nature
  • Original Article


AbstractChanges to the environment often affect animal behavior at the individual and group levels. For aquatic species, disturbances such as heavy rains and runoff may create a highly turbid (i.e., cloudy or visually obscured) environment, which potentially may affect individual interactions and group coordination. Surprisingly, we know little about how decreases in water clarity may influence important collective behavior, such as shoaling in fishes. We hypothesize that differences in water clarity would alter collective movement in fishes. We used an automated video tracking software to collect and process continuous, high-resolution spatial data in both clear and turbid waters. We studied two species of fishes that rely on vision for shoaling, the red shiner (Cyprinella lutrensis) and the sand shiner (Notropis stramineus). For each species, we used 20 groups of five fish each in a mixed-model design with three turbidity treatments: 0, 50–150, and 200–300 nephelometric turbidity units (NTUs). There were species-specific differences, but the patterns of response to turbidity were similar. Both species experienced decreased collective behavior in response to turbidity as indicated by significant increases in interfish distances and shoaling area as well as decreases in velocity. These findings show that turbidity may significantly influence collective behavior and group structure and are consistent with (but not conclusively so) a sensory limitation causation. We also provide basic knowledge in an area that is understudied and may be useful for conservation and management objectives, especially at a time when so many fishes are threatened due to habitat degradation and alteration.Significance statementCollective behavior, i.e., coordinated behavior of groups of animals that often increases survivorship and fitness, occurs in many animals, e.g., schooling in fishes, flocking by birds, and herding by mammals. Habitats are being altered worldwide by human activities such as construction and agriculture. Using fishes, we studied how disruptions to the environment would alter collective behavior. Natural and human disturbances cause higher sedimentation and nutrient loads in aquatic habitats, causing water to become murky, i.e., turbid. We developed and used a computer program to study swimming patterns of shoaling fishes in such conditions. We found that fishes formed and maintained groups less efficiently as water became more turbid. Studies at various levels of the organization are essential in understanding the impacts of such disturbances to habitats, and this includes how disturbances to the environment can alter the collective behavior of fishes.

Report this publication


Seen <100 times