So it seems that it is not so much physiological stress , but competition that decides whether most species will persist in the face of climate change. The enormous adaptability of most plants and animals is demonstrated by agriculture, domestic gardens, botanic gardens and zoos where species from extraordinarily different original environments can often survive so long as competition is kept at bay. These special cases suggest that maintaining the stability of the species composition, that is controlling inputs of weeds and pest animals, is the critical strategy. In fact now that human land use changes have changed most natural areas into islands it seems appropriate to use the example of natural islands to guide us in choosing a species survival strategy. If we adopt the basic island model, then we have to resolve a paradox about stability and change, especially in the case of small islands .
Small islands risk the loss of species due to stochastic shocks - fires, droughts, disease, etc.
This implies that species mobility is important. However small islands are more prone to invasion by weeds and pests from the surrounding zone. So minimising species mobility is important. Larger bush areas, being able to provide for their own restocking, do not raise this dilemma so severely. So it seems as a universal principle we should not encourage the maximum movement of species in the face of the greenhouse effect.