- The Milltown Island Unit is a mid-channel island in the South Fork Skagit River. The unit is accessible only by boat. A boat launch at the WDFW Skagit Headquarters Unit provides access to the unit and portions of the Skagit River estuary via Freshwater Slough to Steamboat Slough and Tom Moore Slough.
- Island Wildlife Area Unit (wdfw.wa.gov)
The Island Unit is accessible only by boat. A boat launch at the WDFW Skagit Headquarters Unit provides access to the unit and portions of the Skagit River estuary via Freshwater Slough. The unit is a popular waterfowl hunting area. Other recreation includes fishing, wildlife observation, and hiking. A mixture of natural and agricultural crops are grown on the Island Unit to enhance food resources for wintering waterfowl and provide improved hunting opportunity.