Conclusion
Based on recommendations of an international workshop of SDM experts, we have outlined potential sources of uncertainty linked to the various stages of analysis needed to complete an SDM projection into future climates (Table 2). This begins with the need to identify sources of uncertainty during goal setting and at the onset of an analysis (guidelines #1 and 2), while selecting relevant data sources (guidelines #3 and 4), throughout model building and evaluation (guideline #5), right through uncertainty estimation and the interpretation of results (guidelines #6-8), and finally, during the communication of results (guidelines #9 and 10).
Through the application of SDM outputs, researchers and end users may identify important data gaps or other elements that need to be reassessed for clarity; this feedback can lead to iterative improvement of both the analytical process and resulting outputs. The need to build a community of practice that includes a diversity of perspectives and skills for projecting marine species distributions is a challenge and a gap. Partnerships between scientists, practitioners, and managers are necessary to evaluate approaches that can lead to clear and consistent standards and science advice to support a variety of marine spatial planning decisions now and in the years to come.
Many ecosystems have species and environmental data shortfalls that will limit a modeler’s ability to minimize some sources of uncertainty in SDM projections. For example, there are currently few datasets available of downscaled, high-resolution climate variables for marine regions and no coordinated global effort to develop them. However, even in the absence of such data, these guidelines provide practical steps for identifying the relevant sources of uncertainty, quantifying their magnitude, and communicating their effects. Following these guidelines will help practitioners to identify areas of higher confidence where species distributions are not expected to change. SDM projections may represent the best available knowledge to inform management strategies; thus, it is essential to acknowledge and report on uncertainty to avoid poor management decisions. By following the guidelines laid out in this review and communicating the decisions that were made throughout the analysis process, SDM projections can be informative to researchers, managers, and policy makers interested in planning for a changing and uncertain future climate.