INCORPORATING ENVIRONMENTAL UNCERTAINTY INTO SPECIES MANAGEMENT DECISIONS - KIRTLANDS WARBLER HABITAT MANAGEMENT AS A CASE-STUDY

We present a framework for expressing species management objectives th at incorporates the inherent riskiness of species management strategie s. This framework identifies two critical parameters in the management objective: the population level that one would like to achieve and th e minimum acceptable probability of attaining that population objectiv e with a given management strategy-the safety margin. We then explore the implications of imposing a management objective in this form on ha bitat management decisions for the Kirtland's Warbler (Dendroica kirtl andii). We used a stochastic simulation model to generate probability distributions for Kirtland's Warbler population outcomes under differe nt management strategies. The management parameter we varied was rotat ion length of commercial logging, and the cost of each rotation length was calculated as the opportunity cost of not operating at the profit -maximizing rotation length. The cost and warbler population distribut ion associated with each rotation length were then used to derive cost curves for the two critical decision parameters-population level and safety margin. For most of the range of values analyzed, the relations hips between cost and both population objective and safety margin are linear. In addition, the rate at which cost rises with population obje ctive increases as the safety margin required for that objective is ra ised.