- Where glacial water draining off Mount Rainier meets the Puget Sound, the Nisqually River has created a vast, thriving delta. Explore over 4 miles of trails through the Billy Frank Jr. Nisqually National Wildlife Refuge, immersing yourself in the vibrant delta ecosystem. The 762 acres of the refuge offer a temporary home to over 300 species, including eagles, salmon, seals, tree frogs, and many varieties of waterfowl. Despite the tranquility of this site today, the past two centuries of its history were tumultuous. Manmade irrigation ditches built in the early 1900s converted the delta into farmland. Barns constructed during this time can still be seen along the trails within the refuge. The irrigation ditches drained the estuary of water, removing habitat for salmon and other species. In 2009, the largest ditch was removed, starting a process of estuary and ecosystem recovery that is still going on today.