A fish walks into a pharmacy ...
It's the start of a joke – with echoes in reality. Sort of.
Fish aren't being prescribed anti-anxiety drugs. But they are experiencing the effects.
That's because fish and other aquatic creatures are being affected by increasing levels of drug pollution – from human waste or pharmaceutical factory runoff – that then seep into our waterways. Researchers have found more than 900 different pharmaceutical ingredients in rivers and streams around the world. And they're not yet sure how this could change animals' behavior in the wild.
"We can't, you know, dump a bunch of pharmaceuticals into the river," says Jack Brand, biologist at the Swedish University of Agricultural Sciences.
Instead, Brand's team did the next best thing: They conducted a controlled study that implanted pharmaceuticals in Atlantic salmon in Sweden and monitored their migration toward the Baltic Sea.
The results were surprising.
In the salmon, clobazam – an anti-anxiety drug – seemed to increase migration success.
But that doesn't mean scientists should start prescribing salmon anxiety medication anytime soon. The researchers noted that clobazam had other behavioral effects, like making the Atlantic salmon bolder and less social. And when it comes to salmon life beyond migration, there are still a lot of unknowns.
Want to hear more stories about animal behavior? Email us and let us know at shortwave@npr.org.
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This episode was produced by Hannah Chinn and edited by Emily Kwong and Rebecca Ramirez. Tyler Jones checked the facts. Kwesi Lee was the audio engineer.
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