Biodiversity Conservation and Climate Change

In this chapter, you will learn about:

• 1. The scientific evidence for modern climate change

• 2. The current and predicted effects of climate change on biodiversity

• 3. Conservation strategies and policies to mitigate the effects of climate change in efforts of biodiversity conservation

In his remarks above, Daniel Scott was addressing the effects of contemporary climate change on only one nation, Canada, and only one dimension of its national conservation effort, national parks. But although his words are directed to the conditions of one country and one conservation strategy, Scott could just as easily have been speaking of every conservation strategy in the whole world. The most important threats to global biodiversity have traditionally been perceived as habitat destruction, fragmentation, and degradation; overexploitation of species; competition, predation, and displacement of indigenous species by invasive species; and disease. These threats remain obstacles to biodiversity conservation, but conservation efforts to mitigate them, even if confined to single species and individual locations, can be effective if intelligently applied. But another threat now casts an ominous shadow over all other dangers, and, if unaddressed, has the potential to overwhelm any local or regional actions, however well designed or intended, toward conservation goals. That threat is global climate change.

The idea that climate limits species’ distributions is not new. In 1917, the American zoologist Joseph Grinnell, examining such diverse species are the Oregon jay (Perisoreus obscurus), pika (Ochotona princeps), rosy finch (Leucosticte arctoa), redwood chipmunk (Eutamias townsendi ochrogenys), and western meadowlark (Sturnella neglecta), published his assessment of the role of climate in constraining the geographic ranges of these animals (Grinnell 1917). Grinnell did not call his work a “climate study,” but noted, in his own words that “… upon the North American continent, one single factor does happen to loom up as being the most frequent delimiter of distribution, or even the ultimately effective one, in greater or lesser degree, even though other factors be effective also. This factor is temperature” (Grinnell 1917:128).