The Spurwink River is a relatively short (less than five miles) stretch of tidal river that forms much of the border between the towns of Cape Elizabeth and Scarborough. The river system includes a salt-hay salt marsh, an uncommon habitat type in southern Maine and home to several species of plants of special concern including Saltmarsh False-foxglove.
The Spurwink River is a foraging site for a variety of wading birds, including Great Blue Herons, Great Egrets, Snowy Egrets and Glossy Ibises. The river and tidal flats are a key migration stopover for both shorebirds and a diverse array of waterfowl (including Mallards, American Black Ducks, Red-breasted Mergansers, Buffleheads, Common Goldeneyes) in the spring and fall, as well as a foraging area for Common and Least Terns that nest on nearby islands and beaches. In some winters, the uplands around the river attract Snowy Owls.
The east side of the Spurwink River and its associated uplands lie within Cape Elizabeth?s Town Farm District, which is intended to recognize and protect the special nature of the area representing historic, cultural, scenic, natural, and open space qualities that should continue. Threat from major development is therefore limited, at least on the Cape Elizabeth side of the river. Development on the west side of the river has been sparse, though the number of new homes has increased in recent years.
Tidal water in the river is classified as ?SA?, the highest classification signifying the water is an outstanding natural resource that should be preserved because of its ecological importance. Biodiversity Research Institute tested mercury levels in marshbirds from the Spurwink River in 2004 and 2005, and found some of the lowest blood mercury concentrations among a dozen study sites in the northeast (Oksana Lane, Biodiversity Research Institute, unpublished data).
There is a boat launch on Route 77 though parking is limited. The river also may be accessed from the ocean, at its outlet at the north end of Higgins Beach (see Scarborough IBA description). The marsh and surrounding upland are a mix of private and federal (Rachel Carson National Wildlife Refuge) holdings. Specifically, the upper reaches of the river are owned and managed by the Rachel Carson Wildlife Refuge, where duck hunting is allowed in the fall.