Since 1984

What Is the Big Picture?


Extensive Habitat Loss Threatens Carolinian Canada

Carolinian Canada is the southernmost region of Canada and contains more rare and endangered species of plants and animals than any other part of Canada. Over 125 species have been declared at risk and over 400 others are considered rare. Forest cover has been reduced from 80% to 11% and in some places is less than 3%. Wetlands once covered 28% of the land but now are reduced to 5%. Fragmentation of remaining habitats into very small remnants is a further threat. The Carolinian zone occupies only one percent of Canada's land area, but is home to 25% of its people. Not surprising that the Carolinian zone is Ontario's most threatened ecological region, and one of Canada's most threatened.


Photo: Mike Oldham
Eastern Prickly Pear Cactus Opuntia humifusa (Photo: M. Oldham) an endangered plant found only on a few sand spits in southwestern Ontario.

Photo: Badger
American Badger Taxidea taxus jacksoni, an endangered mammal of prairies and savannas, one of Carolinian Canada's imperiled habitats

Conservation efforts in the past have focused on "Island of Green" amongst cities, towns and farms. Carolinian Canada identified 38 critical natural areas in 1984 across the Carolinian zone as requiring urgent action. But over the last decade our scientific understanding has advanced and we realize that these "Island of Green" cannot exist on their own. To remain viable they must be connected one to another in a larger system of connected natural areas, now referred to as a "natural heritage system".

The "Big Picture" analysis identifies such a natural heritage system.

Large, Connected Natural Areas are Needed

Conservation science has shown that some wildlife require large areas of habitat to thrive and reproduce. Many Carolinian species-at-risk are species requiring large habitat areas (see boxes below). These species suffer when habitat is fragmented into small patches. Large areas of habitat offer the best chance for viable populations of a wide variety of species to survive, migrate and propagate. Large habitat areas also need to be linked together by wide corridors of habitat that allow plants and animals to disperse or migrate between larger patches of habitat. A large amount of forest, wetland and other natural habitat in any given region is needed for all native species to thrive and maintain healthy ecosystems including clean water. Carolinian Canada has some of the smallest percentages of remaining habitat in Canada. (Click here for more on How Much Habitat is Enough?)

The threatened Hooded Warbler nests in mature hardwood forests with tall trees and a well-closed canopy. The species is considered area-sensitive, meaning that it requires large areas of forest for nesting. Prior to the 1800s, there was extensive habitat in Carolinian Canada that would have been suitable for hooded warblers. Very little forest cover remains in the Carolinian area of Canada and much of the forest that does remain is highly fragmented. Presently, forest interior covers only about 2% of the land area in the Carolinian Forest region. (Canadian Wildlife Service, Enviroment Canada)
Photo: George PeckThe endangered King Rail requires large marshes with open shallow water that merges with shrubby areas. In fact, birds only return in successive years to large marshes not overgrown with cattails. Originally, the best habitat for king rails was in southwestern Ontario, but most of these wetlands have since been eliminated. Only 10% of the original pre-European settlement marshes remain in the one area of Ontario where the largest component of the species occurs. The quality of the remaining habitat is also deteriorating. (Canadian Wildlife Service, Environment Canada)

The "Big Picture" analysis identifies a natural heritage system of large core natural areas, other significant natural areas and corridors and linkages connecting the system together. It is meant to complement other analyses of natural heritage conducted by municipalities, conservation authorities, provincial and federal departments.

What is a Natural Heritage System?

A natural heritage system includes core natural areas, other significant natural areas and the linking habitat corridors. Potential areas for restoring and enhancing natural areas and corridors are also identified. This approach is advocated in provincial policy documents such as the Natural Heritage Reference Manual and the Significant Wildlife Habitat Technical Guide that support implementation of the Natural Heritage Policy 2.3 in the Provincial Policy Statement. The Provincial Policy Statement also defines "significance" of natural heritage features and functions in terms of a "natural heritage system".

Click to see illustration of a Natural Heritage System
Natmap.jpg (51545 bytes)

Photo: Don Kirk
The Swamp Rose Mallow, Hibiscus moscheutos, a marshland species of Special Concern (Photo: Donald Kirk)
  A wide variety of land uses, including agriculture and forestry, can be complimentary with natural heritage protection. A range of conservation policy tools are also needed including improved land use planning, private land stewardship, incentives, wildlife protection and securing of key habitats through acquisition.

Carolinian Core Natural Areas and Corridors

The Big Picture analysis uses conservation science and state-of-the-art information management technology to identify Carolinian core natural areas, other significant natural areas, and potential habitat corridors to link the natural areas together. The analysis also identifies potential restoration areas to enhance the Carolinian core natural areas, significant natural areas and potential corridors (meta-cores and corridors; view the layers here). In developing the Big Picture Map, a team of experts interpreted the data to refine the boundaries of the Carolinian core natural areas, identify existing linkages between them and to propose the additions.

What Conservation Tools are Needed?

To implement a comprehensive natural heritage system, a comprehensive set of conservation policy tools is also needed. These tools include land use planning, private land stewardship including financial incentives and securing land as parks and conservation land by acquisition and conservation easements. Carolinian Canada has developed an agenda for such a set of tools in the "Practical Options for the Greening of Carolinian Canada".

Pursuit of a Big Picture natural heritage system will result in healthier ecosystems, cleaner water and air and healthier communities for all of us to live in. Cooperative community action will be needed to achieve a region-wide natural heritage system. Landowners need incentives and support to play their part. Municipalities and citizens need to act to secure remaining habitat and restore habitat now lost. The Big Picture maps are an excellent tool for informing ourselves and creating awareness of the importance of local decisions to the health of the entire region.


Big Picture Funding Partners

Ontario Parks
Helen McCrea Peacock Foundation
Lambton Wildlife Incorporated
Hamilton Naturalistsí Club
Sydenham Field Naturalists
Big Picture Network
Visualize the Big Picture
Big Picture Methodology
Conservation Tools
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