Prozac isn’t something that we would normally associate with sea creatures, but a new study published in the Ecology and Evolution journal begs to differ.
Prozac is an antidepressant used to treat depression and some other mental medical conditions. Over the years, it and other medicinal substances have been finding their way into the oceans, via the sewage system.
Its presence in the oceans has a negative effect on marine life, affecting their behaviour and posing a risk to their survival.
To study the effects of prozac on marine animals, researchers at Portland State University (PSU) caught Oregon shore crabs (Hemigrapsus oregonensis) and red rock crab Cancer productus) from the wild.
They exposed the Oregon shore crabs to traces of fluoxetine, the active ingredient in Prozac. In the nine-week study, the crabs subsequently increased their foraging behaviour, and even hunted during the day (a time when they would normally be in hiding). They even fought more frequently with members of their own species, and the bout would often end with one of the fighters being killed in the process.
The research also involved predator trials, in which the red rock crab, a predator, was introduced into the tank.
"The changes we observed in their behaviours may mean that crabs living in harbours and estuaries contaminated with fluoxetine are at greater risk of predation and mortality," said Associate Professor Elise F Granek, from PSU's Department of Environmental Science and Management.