Dynamic reserve site selection

We analyze the problem of choosing sites through time to include in a network of biological reserves for species conservation. When sites cannot all be protected immediately, and excluded sites are threatened by development, planning should factor in both expected biodiversity benefits of sites and development risk. We formulate this problem as a stochastic dynamic integer-programming problem. We find that the timing of selections is critical; conservation budgets available up front yield significantly greater biodiversity protection. We also compare results using optimal and heuristic algorithms. The theory is applied to vertebrate and development threat data from southwestern California. (C) 2003 Elsevier B.V. All rights reserved.