You can argue that Olympic National Park is actually three parks in one, with the mountains, rainforest and coastline. Each of these environments support a unique habitat for it’s fish populations. If you are looking to fish in the mountain region of Olympic National Park, you will be fishing some of the best rainbow trout in western Washington. Lake Crescent was isolated after a landslide thousands of year ago, so it supports an environment for two entirely unique species—the Crescenti and Beardslee trout. Fishing is ideal in these areas of the park in spring and summer.
The Elwha River has recently been restored to it’s native state, both dams removed by 2004—now, it is home to a large Coho salmon population. The best time to catch a salmon is in the fall, when they use the river as a highway to reach the coast for spawning. Steelhead and trout also live in the Elwha River, and the summer is the best time for fishing these species.
If you are looking to fish in the rainforest regions of the park, you will be fishing Winter steelhead. While they are called "Winter" steelhead, they are actually best catch in the spring. The rainforest can experience up to 50 inches of rain in the winter, so waiting until spring lets the water warm up, making the fish more aggressive and more likely for you to catch one.
And lastly, if you are looking to fish along the coast, you will be trying to catch Cutthroat trout, Redtail surfperch and rockfish. Summer and fall are ideal for fishing along the coast. Make sure you are up-to-date on the park’s fishing regulations. You are not required to have a Washington State recreational fishing permit, unless you are fishing on the coast of the Pacific Ocean. However, you are required to carry a Washington State catch record card when fishing steelhead and salmon.