OPTIMALITY IN RESERVE SELECTION ALGORITHMS - WHEN DOES IT MATTER AND HOW MUCH

This paper responds to recent criticisms in Biological Conservation of heuristic reserve selection algorithms. These criticisms primarily co ncern the fact that heuristic algorithms cannot guarantee an optimal s olution to the problem of representing a group of targeted natural fea tures in a subset of the sites in a region. We discuss optimality in t he context of a range of needs for conservation planning. We point out that classical integer linear programming methods that guarantee an o ptimal solution, like branch and bound algorithms, are currently intra ctable for many realistic problems. We also show that heuristics have practical advantages over classical methods and that suboptimality is not necessarily a disadvantage for many real-world applications. Furth er work on alternative reserve selection algorithms is certainly neede d, but the necessary criteria for assessing their utility must be broa der than mathematical optimality. Copyright (C) 1996 Elsevier Science Limited.