Trade-offs and efficiencies in optimal budget-constrained multispecies corridor networks.

Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a network of protected areas. We show that designing corridors for single species based on purely ecological criteria leads to extremely expensive linkages that are suboptimal for multispecies connectivity objectives. Similarly, acquiring the least-expensive linkages leads to ecologically poor solutions. We developed algorithms for optimizing corridors for multispecies use given a specific budget. We applied our approach in western Montana to demonstrate how the solutions may be used to evaluate trade-offs in connectivity for 2 species with different habitat requirements, different core areas, and different conservation values under different budgets. We evaluated corridors that were optimal for each species individually and for both species jointly. Incorporating a budget constraint and jointly optimizing for both species resulted in corridors that were close to the individual species movement-potential optima but with substantial cost savings. Our approach produced corridors that were within 14% and 11% of the best possible corridor connectivity for grizzly bears (Ursus arctos) and wolverines (Gulo gulo), respectively, and saved 75% of the cost. Similarly, joint optimization under a combined budget resulted in improved connectivity for both species relative to splitting the budget in 2 to optimize for each species individually. Our results demonstrate economies of scale and complementarities conservation planners can achieve by optimizing corridor designs for financial costs and for multiple species connectivity jointly. We believe that our approach will facilitate corridor conservation by reducing acquisition costs and by allowing derived corridors to more closely reflect conservation priorities.

Changes in attitudes about importance of and willingness to pay for salmon recovery in Oregon.

Salmon are perhaps the quintessential icon of the Pacific Northwest, affecting the region's culture, politics, and economy. The importance Oregonians place on salmon recovery and their willingness to pay for salmon recovery efforts was assessed biennially between 1996 and 2002 through the Oregon Population Survey. Based on these data, we found that Oregonians appear to have become less supportive toward salmon recovery and salmon recovery efforts over that time period; they were less likely to say salmon recovery is important and chose lower willingness to pay responses in 2002 than in 1996. Attitudes do appear to be related to the economic conditions and demographic composition of residents of the state. In particular, we found that local unemployment rates, age of respondent, and rural county residence are significantly negatively correlated with the respondent's expressed support for salmon recovery efforts. Attributes positively correlated with expressions of support for salmon include male gender, graduate-level education, and American Indian identity. We found that a significant portion of the decline in support is unexplained by the variables included in the analysis.

Ranking the benefits of biodiversity: an exploration of relative values.

Public concern about the alarmingly high rate of biodiversity loss has not been matched by public willingness to bear boundless costs to stem the tide of extinction. Because resources for conservation are limited, setting conservation priorities to use those resources effectively is crucial. To do so in a way that addresses people's most pressing concerns about biodiversity loss, managers and policy makers must understand those concerns. This study investigates preferences for an array of benefits associated with biodiversity and wildlife and the relative importance to people of each. A survey was administered to a sample of the US population to explore public preferences for types of benefits often associated with biodiversity: utilitarian (commodity and recreation), ecological (certain and uncertain), aesthetic, symbolic, and humanistic. Respondents were asked to rank hypothetical species presented in choice sets of three species, each described simply in terms of one type of benefit. A rank-ordered multinomial logit model was estimated to establish a ranking of the benefits and evaluate the sensitivity of the ranking to socio-demographic variables. The means of the sample predictions indicated the relative importance of each type of benefit. Confidence intervals were constructed to evaluate the extent to which the ranks could be distinguished from one another. Ecological functions were most important to survey respondents; commodity-based benefits and human attributes were of moderate importance; and recreation, aesthetics, and symbolic references in literature and art appeared to be least important.