Marine protected areas can make fishers both friends and competitors.

At least, an international study led by Duke University recently found that when the behaviors of cooperation (hanging out in a group while working, as fishers have done for centuries) and competition are kept in balance, better conservation of marine resources can result.

But if things get dog-eat-dog and cooperation really falls off, this could be a threat to the system -- lessening the long-term survival chances of marine protected areas (MPA), their biodiversity and the surrounding communities.

"In Baja California, Mexico, you have these towns where the people have been fishing for generations; fishers are friends to one another and help each other at sea, but at the same time compete with each other to see who catches the most," Xavier Basurto at Duke University, said.

While earlier studies have looked at impacts of one behavior or the other, this one shows that the two actions can be interconnected.

"It's really fascinating to listen to fishers convey what we would call friendly rivalry," Basurto said.

Basically, the study showed that fishing while interacting with long-known or well-liked colleagues can result in an even-handed management of a fishery that is shared by all. In the end, this is better for conserving the marine resources.

The research team was from Innsbruck University, Duke and University of Marburg. They employed several methods, including economic experiments with a basis in game theory (an analysis in which a participant's choice has an outcome that depends on the actions of other participants): to learn positively social and antisocial behaviors among non-fishermen and fishermen in four Baja California communities.

Two of those had primary fishing grounds right next to MPAs. The other two communities had main fishing grounds away from the MPAs. The communities were dependent on fishing but had started to diversify.

One of the key findings was that social equality (or lack thereof) is important to keep in mind in how each community functions and works within the MPA.

"This research indicates that when marine protected areas are established, special attention should be paid to the impact they have on social inequality," Basurto said. "Social inequality can lead to a loss of social cohesion in a community, increasing competitive behavior while cooperative behavior declines."

It's also possible for the establishment of a newly protected area to create both positively social and antisocial reactions -- especially if the processes resulting from them lead to differences in social class, income inequality and different class levels/market diversification.

The bottom line is: If reactions remain in balance, the system could work well, unless income inequality is allowed to become an issue.

The findings were published in the journal Science Advances. 

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