Are Canada’s big box grocery stores in trouble? Recent numbers suggest that supermarket and grocery store sales dropped by more than 3 percent in a single month, with food retail sales dropping by more than 220 million dollars in May. Stats can reports that retail food sales are down in four of the last five months. Meanwhile, convenience and speciality stores are bucking the trend and are faring much better. Sylvain Charlebois from Dalhousie University says the buying trends of consumers are changing when it comes to food, and the big retail grocery chains need to adapt if they’re going to survive.