Nestled within Milwaukie, Oregon, Elk Rock Island stands as a remarkable 13.6-acre natural sanctuary, a testament to the region’s rich geological and ecological history. Transferred from the City of Portland to Milwaukie in April 2016, Elk Rock Island offers a unique opportunity to explore diverse habitats and witness rare plant species, all within a readily accessible location.
Elk Rock Island’s accessibility is itself a marvel. Connected to the mainland by a 40-million-year-old land bridge, visitors can reach the island on foot during low water periods via the Spring Park trailhead at SE 19th Avenue and Sparrow Street. Well-maintained hiking trails meander around the bay and throughout Elk Rock Island, inviting exploration of its natural beauty. As you wander these paths, you’ll be immersed in the island’s diverse habitats, but remember to stay on designated trails to protect both the delicate ecosystem and yourself from poison oak.
The history of Elk Rock Island is interwoven with the early development of Milwaukie. Once part of the original land claim of Milwaukie founder Lot Whitcomb, Elk Rock Island passed through several owners before being acquired in 1904 by Peter Kerr, a prominent figure in Portland’s wheat industry. Kerr’s ownership marked a notable period in the island’s history, including the construction of the Friar’s Club, a once-famous establishment located on Elk Rock Island.
Geologically, Elk Rock Island is exceptionally significant. It represents a portion of an ancient volcano that erupted approximately 40 million years ago. The resulting lava flows solidified into Waverly Heights Basalt, the island’s predominant bedrock. This jagged basalt is believed to be the oldest exposed rock in the Portland area, predating the more widely recognized Columbia River Basalts by millions of years. Exploring Elk Rock Island is like stepping back in geological time.
Elk Rock Island’s diverse topography supports an impressive array of seven distinct habitat communities. These include:
- Willamette River Floodplain
- Emergent Wetland
- Mesic Upland Forest
- Riparian Forest
- Cliff Face
- Xeric Upland Forest
- Willamette Valley Grassland
Each of these habitats plays a vital role in supporting a wide variety of wildlife. From birds and mammals to reptiles, amphibians, and invertebrates, Elk Rock Island provides essential food, shelter, and breeding grounds, making it a crucial haven for biodiversity within the urban landscape of Milwaukie.
