Walking the trails at Bonyun Preserve, you will see a variety of natural areas that support diverse flora and fauna.  A tidal inlet on Mill Cove’s salt marsh supports wading birds such as snowy egret and great blue heron, as well as migrating shorebirds. Mixed old-growth woods of white pine, oak, and hemlock are habitat for woodpeckers and songbirds.

Bonyun Preserve is conservation land managed primarily for the preservation of wildlife. The Preserve is open free of charge to the public from dawn to dusk. Help us protect what you have come to enjoy. Natural areas are delicate.

Westport Island is underlain by granite bedrock, covered for the most part with thin, relatively poor acidic soils.

The general landscape was shaped by events that occurred during the pleistocene epoch, which began about 2 million years ago. There were at least four periods of glaciation during which huge ice sheets covered all of Lincoln County.
The last major glaciation spread southeast about 18,000 years ago. As it moved, the glacier ground up rocks beneath it and deposited this newly eroded material as a compact layer of glacial till. The sheer weight of the ice sheet depressed the land surface, while the large quantity of water tied up in the ice lowered the surface of the sea by as much as 350 feet.

As the ice melted the land began to rebound and emerge from the sea. This emergence lasted from about 13,000 to 10,000 years ago when sea level was 180 feet below the present level. Since that time, a slow submergence of the land has brought the sea up to its present level.

From US-1, take ME-144 south 10 miles to second intersection with West Shore Road (Lower). Turn Right, go 0.25 miles to parking lot and kiosk on left. 

The Maine TrailFinder website has a description and map of a hike at Bonyun Preserve.

This trail on Westport Island highlights the Sasanoa River Estuary, tidal inlets, mixed old-growth woods, and freshwater marshes.