Corridors & Global Climate Change

The golden toad Bufo periglenes of the Tilaran Mountains of Costa Rica may be the first extinction caused by the ongoing changes in global climate. Although the most significant changes in temperature are predicted to occur in the North Temperate or Polar regions, temperature & rainfall patterns will change enough in the tropics to effect human welfare, ecosystem processes & biodiversity.

        There have been major climatic fluctuations in the past, so why should the present changes be of concern? When the climate changes, organisms can either adapt, move or die. From the point of view of biodiversity and ecosystem processes, there are at least three major differences between the present and the past: (1) the rate of change may be greater than the past, and (2) habitat fragmentation has removed the natural corridors that facilitated the migration of organisms to areas with favorable conditions and (3) climate change appears to interact synergistically with human-caused degradation & destruction of habitat to exacerbate disturbance.

        As the climate changes, reserves that were once suitable for preserving species may become unsuitable. One solution is to create a network of reserves connected by corridors between them. One of the most important examples is the Northern Rocky Mountain Ecosystem Initiative. Corridors may be a great strategy if they work, but they are expensive and difficult to maintain.

        Costa Rica contains some of the most interesting and visionary examples of the conservation strategy of creating reserves linked by corridors. We will discuss the existing corridor at La Selva, the restoring corridor in the Guanacaste Conservation Area, the planned corridor in the coastal mountains above Las Cruces, and the much-discussed 'Way of the Panther' corridor through Central America. Will a network of reserves connected by corridors prevent more species from the fate of the golden toad?

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