The island is a low, bare, limestone outcropping, approximately 4 kilometres (2.5 mi) off the western shore of the Quinte peninsula.
[2] It is named after Scotch Bonnet Ridge, a nearby glacial feature, a north–south belt of glacio-lacustrine clay and till.
Ownership of the island was transferred to the Canadian Wildlife Service in 1979, after the Department of Transport declared it surplus.
Later that year it was named the Scotch Bonnet Island National Wildlife Area.
[2] During breeding season large numbers of waterbirds, like herring gulls and double-crested cormorants, raise their young on the island.