Cost‐effective conservation of an endangered frog under uncertainty

How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.     

Evaluating conservation dogs in the search for rare species

Detecting rare species is important for both threatened species management and invasive species eradication programs. Conservation scent dogs provide an olfactory survey tool that has advantages over traditional visual and auditory survey techniques for some cryptic species. From the literature, we identified 5 measures important in evaluating the use of scent dogs: precision, sensitivity, effort, cost, and comparison with other techniques. We explored the scale at which performance is evaluated and examined when field testing under real working conditions is achievable. We also identified cost differences among studies. We examined 61 studies published in 1976–2018 that reported conservation dog performance, and considered the inconsistencies in the reporting of scent dog performance among these studies. The majority of studies reported some measure of performance; however, only 8 studies reported all 3 aspects necessary for performance evaluation: precision, sensitivity, and effort. Although effort was considered in 43 studies, inconsistent methods and incomplete reporting prevented meaningful evaluation of performance and comparison among studies. Differences in cost between similar studies were influenced by geographical location and how the dog and handler were sourced for the study. To develop consistent reporting for evaluation, we recommend adoption of sensitivity, precision, and effort as standard performance measures. We recommend reporting effort as the total area and total time spent searching and reporting sensitivity and precision as proportions of the sample size. Additionally, reporting of costs, survey objectives, dog training and experience, type of detection task, and human influences will provide better opportunities for comparison within and among studies.     

A Conceptual Analysis of the Application of Tradable Permits to Biodiversity Conservation

Abstract: Tradable permits have been applied in many areas of environmental policy and may be a response to increasing calls for flexible conservation instruments that successfully conserve biodiversity while allowing for economic development. The idea behind applying tradable permits to conservation is that developers wishing to turn land to economic purposes, thereby destroying valuable habitat, may only do so if they submit a permit to the conservation agency showing that habitat of at least the equivalent ecological value is restored elsewhere. The developer himself does not need to carry out the restoration, but may buy a permit from a third party, thus allowing a market to emerge. Nevertheless, the application of tradable permits to biodiversity conservation is a complex issue because destroyed and restored habitats are likely to differ. There may be various trade‐offs between the ecological requirements that destroyed and restored habitats be as similar as possible, and the need for a certain level of market activity to have a functioning trading system. The success of tradable permits as an instrument for reconciling the conflicts between economic development and conservation depends on the existence of certain economic, institutional, and ecological preconditions, for example, a functioning institutional framework, sufficient expert knowledge, and adequate monitoring and enforcement mechanisms.     

Standardized reporting of the costs of management interventions for biodiversity conservation

Effective conservation management interventions must combat threats and deliver benefits at costs that can be achieved within limited budgets. Considerable effort has focused on measuring the potential benefits of conservation interventions, but explicit quantification of the financial costs of implementation is rare. Even when costs have been quantified, haphazard and inconsistent reporting means published values are difficult to interpret. This reporting deficiency hinders progress toward a collective understanding of the financial costs of management interventions across projects and thus limits the ability to identify efficient solutions to conservation problems or attract adequate funding. We devised a standardized approach to describing financial costs reported for conservation interventions. The standards call for researchers and practitioners to describe the objective and outcome, context and methods, and scale of costed interventions, and to state which categories of costs are included and the currency and date for reported costs. These standards aim to provide enough contextual information that readers and future users can interpret the cost data appropriately. We suggest these standards be adopted by major conservation organizations, conservation science institutions, and journals so that cost reporting is comparable among studies. This would support shared learning and enhance the ability to identify and perform cost‐effective conservation.     

Reallocating budgets among ongoing and emerging conservation projects

Conserving biodiversity and combating ecological hazards require cost-effective allocation of limited resources among potential management projects. Project priorities, however, can change over time as underlying social-ecological systems progress, novel priorities emerge, and management capabilities evolve. Thus, reallocation of ongoing investments in response to shifting priorities could improve management outcomes and address urgent demands, especially when additional funding is not available immediately. Resource reallocation, however, could incur transaction costs, require additional monitoring and reassessment, and be constrained by ongoing project commitments. Such complexities may prevent managers from considering potentially beneficial reallocation strategies, reducing long-term effectiveness. We propose an iterative project prioritization approach, based on marginal return-on-investment estimation and portfolio optimization, that guides resource reallocation among ongoing and new projects. Using simulation experiments in 2 case studies, we explored how this approach can improve efficacy under varying reallocation constraints, frequencies, costs, and rates of project portfolio change. Periodic budget reallocation could enhance the management of stochastically emerging invasive weeds in Australia and thus reduce the overall risk by up to 50% compared with a static budget. Reallocation frequency and the rate of new weed incursion synergistically increased the conservation gains achieved by allowing unconstrained reallocation. Conversely, budget reallocation would not improve the International Union for Conservation of Nature conservation status of threatened Australian birds due to slow rates of transition among conservation states; extinction risk could increase if portfolio reassessment is costly. Although other project prioritization studies may recommend periodic reassessment and reallocation, our findings revealed conditions when reallocation is valuable and demonstrated a structured approach that can help conservation agencies schedule and implement iterative budget-allocation decisions cost-effectively.     

Cost-effective mitigation strategies to reduce bycatch threats to cetaceans identified using return-on-investment analysis

Globally, fisheries bycatch threatens the survival of many whale and dolphin species. Strategies for reducing bycatch can be expensive. Management is inclined to prioritize investment in actions that are inexpensive, but these may not be the most effective. We used an economic tool, return-on-investment, to identify cost-effective measures to reduce cetacean bycatch in the trawl, net, and line fisheries of Australia. We examined 3 management actions: spatial closures, acoustic deterrents, and gear modifications. We compared an approach for which the primary goal was to reduce the cost of bycatch reduction to fisheries with an approach that aims solely to protect whale and dolphin species. Based on cost-effectiveness and at a fine spatial resolution, we identified the management strategies across Australia that most effectively abated dolphin and whale bycatch. Although trawl-net modifications were the cheapest strategy overall, there were many locations where spatial closures were the most cost-effective solution, despite their high costs to fisheries, due to their effectiveness in reducing all fisheries interactions. Our method can be used to delineate strategies to reduce bycatch threats to mobile marine species across diverse fisheries at relevant spatial scales to improve conservation outcomes.     

Combining Auctions and Performance‐Based Payments in a Forest Enrichment Field Trial in Western Kenya

Cost‐effectiveness is an important aspect in the assessment of payments for environmental services (PES) initiatives. In participatory field trials with communities in Western Kenya, we combined procurement auctions for forest enrichment contracts with performance‐based payments and compared the outcomes with a baseline scenario currently used by the Kenyan Forest Service. Procurement auctions were the most cost‐effective. The competitive nature of the auction reduced contracting expenses (provision costs), and the result‐oriented payments provided additional incentives to care for the planted seedlings, resulting in their improved survival rates (service quantity). These gains clearly exceeded increases in transaction costs associated with conducting an auction. The number of income‐poor auction participants and winners was disproportionately high and local institutional buy‐in was remarkably strong. Our participatory approach may, however, require adaptations when conducted at a larger scale. Although the number of contracts we monitored was limited and prohibited the use of statistical tests, our study is one of the first to reveal the benefits of using auctions for PES in developing countries. Combinando Subastas y Pagos Basados en Desempeño en un Ensayo de Campo de Enriquecimiento de Bosques en el Oeste de Kenia     

Prioritizing debt conversion opportunities for marine conservation

Incentivized debt conversion is a financing mechanism that can assist countries with a heavy debt burden to bolster their long-term domestic investment in nature conservation. The Nature Conservancy, an international conservation-based nongovernmental organization, is adapting debt conversions to support marine conservation efforts by small island developing states and coastal countries. Prioritizing debt conversion opportunities according to their potential return on investment can increase the impact and effectiveness of this finance mechanism. We developed guidance on how to do so with a decision-support approach that relies on a novel threat-based adaptation of cost-effectiveness analysis. We constructed scenarios by varying parameters of the approach, including enabling conditions, expected benefits, and threat classifications. Incorporating both abatable and unabatable threats affected priorities across planning scenarios. Similarly, differences in scenario construction resulted in unique solution sets for top priorities. We show how environmental organizations, private entities, and investment banks can adopt structured prioritization frameworks for making decisions about conservation finance investments, such as debt conversions. Our guidance can accommodate a suite of social, ecological, and economic considerations, making the approach broadly applicable to other conservation finance mechanisms or investment strategies that seek to establish a transparent process for return-on-investment decision-making.     

An economic evaluation framework for land-use-based conservation policy instruments in a changing climate

Climate change is a key threat to biodiversity. To conserve species under climate change, ecologists and conservation scientists suggest 2 main conservation strategies regarding land use: supporting species’ range shifts to enable it to follow its climatic requirements by creating migration pathways, such as corridors and stepping stones, and conserving climate refugia (i.e., existing habitat areas that are somewhat buffered from climate change). The policy instruments that could be used to implement these conservation strategies have yet to be evaluated comprehensively from an economic perspective. The economic analyses of environmental policy instruments are often based on ecological effectiveness and cost-effectiveness criteria. We adapted these general criteria to evaluate policy instruments for species’ conservation under climate change and applied them to a conceptual analysis of land purchases, offsets, and conservation payments. Depending on whether the strategy supporting species’ range shifts or conserving climate refugia is selected, the evaluation of the policy instruments differed substantially. For example, to ensure ecological effectiveness, habitat persistence over time was especially important for climate refugia and was best achieved by a land-purchase policy instrument. In contrast, for the strategy supporting range shifts to be ecologically effective, a high degree of flexibility in the location of conserved sites was required to ensure that new habitat sites can be created in the species’ new range. Offset programs were best suited for that because the location of conservation sites can be chosen comparatively freely and may also be adapted over time.     

Projecting biodiversity benefits of conservation behavior-change programs

Biodiversity loss is driven by human behavior, but there is uncertainty about the effectiveness of behavior-change programs in delivering benefits to biodiversity. To demonstrate their value, the biodiversity benefits and cost-effectiveness of behavior changes that directly or indirectly affect biodiversity need to be quantified. We adapted a structured decision-making prioritization tool to determine the potential biodiversity benefits of behavior changes. As a case study, we examined two hypothetical behavior-change programs––wildlife gardening and cat containment––by asking experts to consider the behaviors associated with these programs that directly and indirectly affect biodiversity. We assessed benefits to southern brown bandicoot (Isoodon obesulus) and superb fairy-wren (Malurus cyaneus) by eliciting from experts estimates of the probability of each species persisting in the landscape given a range of behavior-change scenarios in which uptake of the behaviors varied. We then compared these estimates to a business-as-usual scenario to determine the relative biodiversity benefit and cost-effectiveness of each scenario. Experts projected that the behavior-change programs would benefit biodiversity and that benefits would rise with increasing uptake of the target behaviors. Biodiversity benefits were also predicted to accrue through indirect behaviors, although experts disagreed about the magnitude of additional benefit provided. Scenarios that combined the two behavior-change programs were estimated to provide the greatest benefits to species and be most cost-effective. Our method could be used in other contexts and potentially at different scales and advances the use of prioritization tools to guide conservation behavior-change programs.