Skip to main content


The Frontenac Arch Biosphere has an astonishing wealth of animal life. As with the terrific diversity of the flora of the region, the Biosphere's variety of animals owes to several key factors. These are the fact that the region is at the intersection of major continental migration routes, the region has a complex geology and rugged landform, and climate effects.

FaunaThe Biosphere is at a crossroads of migration routes. The north-south route is the Frontenac Arch itself - a bridge of Canadian Shield from the Algonquin and Laurentian highlands to the Adirondack Mountains. This rugged granite landform is the worn-down roots, the very basement rocks, of a billion year-old mountain chain. This land-bridge provides a common ground, of sorts, between the forests of Appalachia and the boreal.

The east-west route is the St. Lawrence Valley, which is the route from the Great Lakes heartland of the continent to the Atlantic coast.

Long-term migrations are far more subtle than the season to season migrations of birds with which we are more familiar. Mammals - with the exception of bats - most insects, reptiles and amphibians move about in search of food, mates or opportunity, and their rangings may bring them new new parts of what they may just see as familiar landscapes. However it happens, the north-south, and east-west routes that intersect here have enriched our Biosphere's natural world.

Fauna is often quite specialized in needs for food, shelter, temperature ranges among other factors. There are many generalists, such as crows, coyotes and raccoons, but animals such as salamanders, songbirds and more specifically, insects have more particular requirements. It happens that this region abounds in niche opportunities.

The rugged landscape means that there are literally millions of slopes and valleys, oriented to every and all points of the compass. As a result, there are hot, sunny, sheltered, cool, windswept, step, gentle, rocky, cliff-faced, gravel, moist, dry - and all other character of slopes one can think of. Valleys are equally complex, where they may be lake or wetland filled, level plains of post-glacial lake-bottom clays, dry ravines, bogs, fens, sand or gravel beds.

The terrain interplays with the complexities of the region's climate and weather patterns. The Frontenac Arch is the landform that confines Lake Ontario to its basin, and the lake becomes a great moderator of the climate from season to season, lessening the seasonal extremes and prolonging the swing of each season. The vast volume of the lake is slower than land to cool in the fall, and retards the warming of the land in spring. While we expect that the growing season would be shorter as one moves north, the moderating lake allows a longer growing season at the upper end of the St. Lawrence Valley than one sees moving eastward down the valley, for some hundreds of kilometres. Coupled with the effect of slopes facing to or from the sun, climate plays a large part in the conditions which modify the so-called normal ranges of animals, and plants.

An example of the cumulative effects of migration routes, geology and climate here is the eastern rat snake. At one time, its range covered a large area of eastern North America. Now, there are limited places where this large and gentle snake is found, having quite isolated remnants of the former range, all others than the Biosphere being southerly. One of its last population areas is the Frontenac Arch Biosphere, where the climate, rocky dens for winter refuge and food sources continue to provide suitable conditions.

Other examples are that the region has both southern and northern flying squirrels, where the southern species favours deciduous forests, and the northern cousin resides in mixed coniferous woodlands. From time to time, opossums southern species not capable of severe withers crosses northward through the islands of the Arch to make local appearances. This region hosts both cottontail rabbits, a southerner; and snowshoe hares.

There are many "species at risk" in the region, totaling 34 for both plants and animals. Species at risk are any naturally occurring, native species that are in danger of extinction or disappearing from geographic areas. Sometimes called the "endangered species list", these plants and animals fall into various levels of endangerment, from species of concern to extinct. A large number of such species in our area is due to the fact that there are actually refuge favourable conditions, lesser risk factors and available habitats to support species that may have been eliminated from other parts of their normal range. With conservation efforts based on studies and modelling programs, the Biosphere region may continue to host species that are otherwise more seriously threatened in surrounding areas.

For more information, visit: