On a glorious, sunny day years ago after biking up the Resurrection Pass Trail to Juneau Lake, my companion and I paused to enjoy the spectacular alpine view and cool breeze by the water. The initial tranquility was brief. Within minutes, tens of flies the size of house flies landed on us and, with little delay, bit. These were unlike sneaky mosquitoes or black flies that can often take a blood meal without being detected; these things hurt!