Cocaine pollution in waterways appears to be changing salmon behavior, study says
(Gray News) – A new study shows cocaine contamination in waterways could impact the movement of Atlantic salmon and lead them to swim farther.
The study, a joint effort by Australia’s Griffith University and the Swedish University of Agricultural Sciences, was published in the journal Current Biology on April 20.
According to the study, cocaine and its byproducts are increasingly being detected in waterways worldwide. Once in the environment, they can pose a threat to wildlife, such as salmon.
The study focused on three groups of 2-year-old hatchery fish that were given tiny implants.
One group was given a tiny implant of cocaine, while another was given an implant of cocaine’s main byproduct, benzoylecgonine. The third group was the control group and was given no added chemicals.
The researchers then tracked the fish’s movements in Lake Vättern, a large natural lake in Sweden, over eight weeks.
The study reported the group exposed to benzoylecgonine swam almost twice as far per week as the control group. The researchers also noted the fish exposed to benzoylecgonine dispersed about 7.6 miles farther than the control group.
They also said the group exposed to cocaine fell between the other two groups.
The study concluded that cocaine-related pollution in waterways could affect salmon’s spatial ecology and influence their habitat use and dispersal patterns.
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