San Juan Island National Historical Park preserves and protects a diverse variety of natural features, ecological communities, ecosystem components, and niche habitats in its two units on San Juan Island.
San Juan Island is one of the two largest islands in the San Juan Archipelago. North of Puget Sound, the San Juan Islands are nestled between Canada’s Vancouver Island, the Strait of Georgia, the inland coast of northwest Washington state, and the Strait of Juan de Fuca.
The San Juan Islands lie in the center of the geographically, culturally and ecologically defined region known as the Salish Sea. The name is derived from the Central Coast Salish language group of First Nations peoples.
The archipelago includes more than 800 islands, islets, rocks, and reefs and 370 miles of tidelands. Landscape, climate, and geological history have, and continue to influence the development of the Salish Sea ecosystem. The San Juan Archipelago is internationally recognized as an exceptional, fairly pristine ecosystem. The environmentally sensitive coastal areas of the San Juan Islands are regarded as among the more diverse intact marine ecosystems in the nation.
However this fragile region is not without its challenges and threats to environmental health for its waters, air and living things. San Juan Island National Historical Park’s rich terrestrial and water resources are especially significant and valuable in a place and time of shrinking open spaces and dwindling undeveloped shoreline.
The park’s 1752 acres make it the second largest protected public space in the San Juans. With 6.1 miles of shoreline, San Juan Island NHP protects the most public shoreline in the San Juan Archipelago. From American Camp’s South Beach to English Camp’s 650 ft. Mt.Young, the park’s varied landforms are the legacy of repeated glaciation. Rolling terraced hills mix with occasional steep slopes and bedrock outcrops.
Surrounding waters moderate island temperatures and produce a typically mild maritime climate. Winters are overcast and rainy with occasional snow. When the storm tracks shift northward in summer, San Juan Island, lying in the rainshadow of the Olympic Mountains, is left exceptionally dry and sunny. Plant and animal communities reflect these environmental and topographical contrasts. Windswept grasslands dominate semi-arid sites at American Camp, home to a variety of raptors and songbirds.
Where water is more plentiful at English Camp and on north-facing slopes at American Camp, dense forests of Douglas fir, western redcedar, western hemlock, and grand fir thrive. Red alder, a sun loving pioneer species is found in edge and clearing environments. On the rocky, drier, southfacing slopes of Mount Young, stands of Garry oak, Pacific madrone, big leaf maple, and Douglas fir are predominant. Spring and summer wildflowers blanket grassy knolls and open hillsides. Sand/gravel beach alternates with rugged shoreline, and sheltered bays and coves harbor shorebirds, seals, river otters, and an array of intertidal life.
