You may have noticed a small blue and white fish logo on the packaging of fish products you buy in the store. This is the ecolabel of the Marine Stewardship Council (MSC), which denotes wild-caught fish and seafood and a promise that the product was harvested using sustainable fishing practices.
Researchers at NTNU therefore decided to test what would happen if store customers were told that lots of other shoppers bought MSC-labelled seafood. They thought customers would go with the flow and act like "everyone else" – but the results did not quite turn out the way the researchers imagined.
Through her doctorate in environmental psychology, Isabel Richter has studied how people can be motivated to eat more sustainable seafood. She was granted permission to carry out an experiment in various grocery stores in Norway and Germany.
"The signs had almost no effect on the sale of sustainable salmon and cod. Instead, the researchers discovered that the total sales of seafood products, both with and without ecolabelling, skyrocketed.
"We wanted to motivate people to eat more sustainable seafood, but instead we motivated them to eat more of all kinds of seafood – including non-sustainable options. Ecolabelling is a very common form of sustainability communication, so it was important for us to find out what had really happened here," says Richter.
Since the researchers only had sales figures from the store trials and hadn't interviewed customers, they decided to conduct a new laboratory study.
"We think what might work is to communicate what customers should do, and not what they shouldn't do," says Richter.
For example, if we ask people not to choose endangered tuna the next time they buy sushi, they'll just want to have tuna. Instead, we should recommend that they choose sustainable scallops for their sushi.
"And even without the ecolabel, fish already has so many other labels: the Nordic keyhole label, that it's antibiotic-free, locally produced, and so on. People don't know what all the different labels mean," Richter says.
Article in Sustainability: A Social Norms Intervention Going Wrong: Boomerang Effects from Descriptive Norms Information, by Isabel Richter, John Thøgersen and Christian A. Klöckner.