Salmon are swimming faster due to painkillers dumped into rivers: study

Wild salmon are swimming quicker due to painkillers and other drugs dumped in rivers and the sea, reveals new research.Traces of a sleeping pill shortened the time it took for juvenile salmon to navigate through two hydropower dams along their regular migration route that usually slow up the journey, say scientists.Levels of clobazam — a medication often prescribed for sleep disorders — also increased the river-to-sea migration success of juvenile salmon in the wild, according to the findings of the largest study of its kind.An international team of international researchers, led by the Swedish University of Agricultural Sciences investigated how pharmaceutical pollution affects the behavior and migration of endangered Atlantic salmon.They warned that their findings, published in the journal Science, may seem beneficial, but any change to the natural behavior and ecology of a species is likely to have wider negative consequences.Dr.Marcus Michelangeli, of Griffith University’s Australian Rivers Institute, emphasized the increasing threat of pharmaceutical pollution to wildlife and ecosystems worldwide.He said: “Pharmaceutical pollutants are an emerging global issue, with over 900 different substances having now been detected in waterways around the world.“Of particular concern are psychoactive substances like antidepressants and pain medications, which can significantly interfere with wildlife brain function and behavior.Michelangeli noted that the study’s “real-world” focus sets it apart from previous research.He said: “Most previous studies examining the effects of pharmaceutical pollutants on wildlife have been conducted under controlled laboratory conditions, which don’t fully capture the complexities of natural environments.“This study is unique because it investigates the effects of these contaminants on wildlife directly in the field, allowing us to better understand how exposure impacts wildlife behaviour and migration in a natural con...