The naivety of the young..salmon!

Humans aren’t the only ones who might experience culture shock – and for some animals a failure to adjust to the novel “culture” of an invasive species might be lethal!  This may be especially true for aquatic species, which generally don’t have parents to teach them any better, and have to rely on innate responses to survive predators.  A recent Olden Lab paper published in the journal Freshwater Biology (March 2012) documents this story for juvenile salmon in the Pacific Northwest and invasive smallmouth bass. Young salmon innately recognize and run from the smell of northern pikeminnow – a native predator – but either don’t recognize the smell of non-native smallmouth bass or associate it with danger.  We documented the behavioral responses of salmon to the cues of both predators in laboratory and field experiments, adding to the body of literature on how aquatic species and ecosystems respond (or don’t!) when a mysterious stranger moves into town.  You can link to the article here – you can also check out a short video clip below which shows the differences in behavior to the two predator odors that we saw in our laboratory experiment.