Manitoulin Island, the largest freshwater Island within an inland lake in the world, is situated in the North Channel of Lake Huron of the Great Lakes region. It is approximately 100 miles long and 40 miles wide at the widest point. The population is currently about 12,000 people, residing in an area of 1090 square miles.
Geologically, Manitoulin’s features are defined by limestone or glacial deposits derived from limestone. The Southern shore is composed of hard dolomite forming a flat pock-marked silurian pavement, while the entire length of the North shore is an outcropping of cliffs, and is an extension of the Niagara Escarpment.
The recession of the Wisconsin Glacier, which covered Ontario in a vast sheet of ice 20,000 years ago, resulted in the formation of Manitoulin Island. However, during that time the Island has undergone a number of changes and has only existed in its present form as an Island (not Islands) for less than 4,000 years.
The climate is influenced by two factors. The region is in the interior of North America, and as such should experience a continental type of climate: hot summers, cold winters. However, its location in the Great Lakes system acts as a buffer and moderates these extremes. These factors also effect the vegetation as well as the growing season. The water provides protection from the early killing frosts which are so prominent in Northern Ontario, while at the same time offering less extreme humidity and dryness as so often seen in the South.
Manitoulin hosts 1,167 species of flora. Canada contains about 4,000 species, so by comparison Manitoulin Island has 28% of all species found in Canada in an area occupying only 0.028% of the country.