The Merced River passes through one of the most scenic valleys in the world. The river flows west from its headwaters near the crest of the Sierra, down through Yosemite National Park, through the foothills in Mariposa County, to it's confluence with the San Joaquin River on the central valley floor. Despite the crowds of visitors angling pressure is extremely light in Yosemite Valley. The area below the park provides a great opportunity to catch some fish away from the crowds. The river in the El Portal Area is managed with special regulations to protect rainbow trout which often grow larger than 12 inches due to the favorable growing season and conditions in this section of the river.
Surveys conducted on the river give biologists valuable information to follow trends in the fishery.