Cocaine pollution alters the movement and space use of Atlantic salmon (Salmo salar) in a large natural lake

Abstract

Cocaine and its metabolites are increasingly being detected in aquatic environments worldwide. While previous research has demonstrated that these substances can affect brain function and behavior in wildlife, this research has exclusively been conducted under artificial laboratory conditions. How cocaine pollution affects animal behavior in the wild is, thus, unknown. Here, we combine slow-release chemical implants with acoustic telemetry tracking to reveal how environmentally realistic levels of cocaine and its main metabolite, benzoylecgonine, affect the movement of Atlantic salmon (Salmo salar) smolts in a large natural lake (Lake Va¨ttern, Sweden). Benzoylecgonine exposure increased weekly movement rates of fish in the wild, with exposed fish swimming up to ∼1.9 times farther per week relative to controls. In addition, benzoylecgonine-exposed fish dispersed up to ∼12.3 km farther than control conspecifics. These results indicate that cocaine-derived pollutants can alter fish spatial ecology, potentially influencing habitat use, trophic interactions, and population-level dispersal patterns in natural ecosystems.

Keywords

behavioral ecotoxicology; chemical; ecology; pollution; survival; telemetry; movement ecology; global change; Anthropogenic change

Published in

Current Biology
2026, volume: 36, number: 8, pages: 2018-2027.e4

SLU Authors

• Brand, Jack

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    
  • Zoological Society of London

• Palm, Daniel

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Cerveny, Daniel

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    
  • University of South Bohemia in České Budějovice

• Michelangeli, Marcus

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    
  • Griffith University

• Bose, Aneesh

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    
  • Max Planck Institute of Animal Behavior

• Mccallum, Erin

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Hellström, Gustav

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Brodin, Tomas

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Bertram, Michael

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    
  • Monash University
  • Stockholm University

UKÄ Subject classification

Fish and Aquacultural Science
Environmental Sciences
Ecology

Publication identifier

• DOI: https://doi.org/10.1016/j.cub.2026.03.026

Permanent link to this page (URI)

https://res.slu.se/id/publ/146849