Elk Rock Island

Milwaukie took ownership of Elk Rock Island from the City of Portland in April 2016, adding 13.6 acres of natural area to the community. It contains seven distinct habitats, including vernal pools, which are home to many amphibians and other forms of aquatic life. More than 50 rare and unique plant species can also be found on the island.

Access
Elk Rock Island is connected to Milwaukie by a 40-million-year-old land bridge. The island is accessible at low water at the Spring Park trailhead on SE 19th Avenue and Sparrow Street. Follow the hiking trails that wind around the bay and through the island. Enjoy the natural habitat while remaining on the designated paths to avoid the poison oak. 

History
Elk Rock Island was a portion of Milwaukie founder Lot Whitcomb’s original land claim. After ownership was passed around between several individuals for about 40 years, including a few members of Whitcomb's family, the island was eventually purchased in 1904 by Peter Kerr, a prominent Portland businessman in the wheat industry. Kerr helped build the infamous Friar’s Club, once located on Elk Rock Island, and owned a home directly across the river from the island in the Dunthorpe area.

Geology
The island represents part of an ancient volcano that erupted about 40 million years ago. The lava flows formed the predominant bedrock called Waverly Heights Basalt. Large and jagged, the basalt may be the oldest exposed rock in the Portland area. It substantially predates the more common Columbia River Basalts which formed 10 to 25 million years ago. 

Habitats
Seven habitat communities have been identified on the Island:

• Willamette River Floodplain
• Emergent Wetland
• Mesic Upland Forest
• Riparian Forest
• Cliff Face
• Xeric Upland Forest
• Willamette Valley Grassland

Each of these communities provide food, cover, roosting, and wintering and summer breeding habitat for numerous species of birds, mammals, reptiles, amphibians, and invertebrates.