Several recent studies have investigated the importance of incorporating better information on economic costs into the conservation planning process (e.g., Ferraro 2003a,b; Ferraro 2004; Balmford et al. 2003; Naidoo et al. 2006). These studies typically find that conservation plans that explicitly account for both ecological benefits and economic costs are substantially more cost-effective than those that only account for ecological benefits. In some cases, conservation plans developed using economic information alone were found to be more cost-effective than those developed using ecological information alone (though see Newbold and Siikamaki 2009 for a counter-example). Based on these results, Naidoo et al. (2006) suggest there may be a need for a “radical shift in conservation research” towards a greater focus on estimating economic costs rather than ecological benefits. In this paper we investigate further the value of additional ecological and economic information for systematic conservation planning.
We begin by summarizing earlier results showing how the variations of and correlation between ecological benefits and economic costs among sites influences the cost-effectiveness of conservation plans developed with limited information. We expand on earlier results by exposing a potential asymmetry in the value of benefit versus cost information depending on the shapes of the distributions of expected benefits and costs among the sites. Next we calculate an upper bound on the value of additional ecological or economic information by determining the maximum amount of funds an optimizing decision-maker would be willing to re-allocate from site protection to information collection activities, assuming that perfect information on ecological benefits can be obtained while holding constant the uncertainty surrounding economic costs, and vice versa. This analysis clarifies the role of the initial precision of ecological and economic information in determining the value of additional information of either type. Lastly, we describe an approach for selecting sites and determining how much effort to devote to the collection of additional ecological and economic information at each site simultaneously. Our approach expands on the method of Polasky and Solow (2001) by expressing the value of additional information in dollars as well as ecological units, by accounting for the costs of information collection, and by providing a means to determine the optimal level of information collection effort at each site given any initial budget allocation.