Conservationists have established land reserves to preserve the last remaining habitat for certain species whose survival depends on the existence of such habitat  A grove of trees in Mexico that provide habitat for North American monarch butterflies in winter is a typical example of such a land reserve
If global warming occurs as predicted, however, the temperature bands within which various types of vegetation can grow will shift into regions that are currently cooler
If global warming occurs as predicted, the conservation land reserves will cease to serve their purpose.