Harris Island was part of the former Serpent Mounts Provincial Park and information about it can be found in the 1985 management plan. While the main part of the park has now been returned to Hiawatha First Nation, Ontario Parks still manages and owns Harris Island.

The western half of the island is mainly marsh and may allow waterfowl hunting. The eastern half of the island features some upland forest habitats and is classified as a nature reserve.

The island is difficult to access and since much of it is classified as a nature reserve, birders should consider visiting other areas rather than disturbing the island.