THE Dolphin Research Institute has renewed calls for boaters to be careful around dolphins in Port Phillip Bay after young calves were “clearly distressed by vessels” earlier this month.There are at least seven dolphin calves only weeks old and are still totally reliant on their mother, the institute’s executive director Jeff Weir said. But he said researchers had unfortunately witnessed “profound tail slapping,” where dolphins “vigorously bang their tail fluke on the water in a graphic distress response that can be seen and heard hundreds of metres away”. “It’s a sign that vessels need to give them space,” he said.“The…