The Marginal Cost of Species Preservation: The Northern Spotted Owl

Because species survival is not certain, the decision to "save" a species is not an all-or-nothing choice but rather a marginal one. The appropriate unit for both benefit and cost functions is the likelihood of survival and the appropriate question is how certain we want to be of species survival. The intensity of the species preservation debate is also fired by strong equity concerns. We illustrate these points for the case of the northern spotted owl by constructing a marginal cost curve for its survival and by disaggregating welfare loss by region and by market level.