In Alaska's Katmai National Park, there are brown bears everywhere. This sow was walking with her three cubs when the last one in line was suddenly startled by something...he stood up, looked around and then continued to bring up the rear when he saw nothing out of the ordinary. Equipment was Nikon D4s, Nikon 600mm f/4, Gitzo tripod with Wimberely head; settings were f/5.6, 1/1000 sec., ISO 2500.