BEFORE the reservation system begins in Rocky Mountain National Park on May 27, and AFTER the snow melts but BEFORE the bulk of the spring runoff hits is a good time to fish Moraine Park. NOW is the time brook and brown trout begin to leave the deep pools where they survived the winter and they’re hungry. Emerger patterns and Adam’s dry flies will get their attention. Of course, the old reliable San Juan worm is still a favorite. If you’re mostly catching small fish, get stealthier.