Fisheries are a surprisingly common reason for conflict between countries. Between 1993 and 2010, 11 percent of militarized interstate disputes (MIDs) – conflicts short of war between two sovereign states – involved fisheries, fishers, or fishing vessels. While the conflicts often involve fresh fish, the implications for global peace and prosperity stink like fermented herring. As climate change threatens to change fish habitats, new governance strategies may be needed to prevent these “fishy MIDs” from sparking broader conflicts.