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Climate change is increasing stream temperatures and thereby changing habitat suitability for a variety of freshwater fishes. We investigate how suitable stream habitat for rainbow trout (Oncorhynchus mykiss), a valuable cold-water species, may change in British Columbia, Canada, currently near the north end of their range. We examine a no-mitigation climate change scenario (RCP 8.5), and one with moderate mitigation (RCP 4.5). We used a watershed-scale regression model incorporating topographic, hydrological and climatic variables to estimate current and projected maximum weekly average stream temperatures throughout the province. We then calculated the potential change in suitable habitat within rainbow trout’s native range, in low- and high-relief watersheds and watersheds with lakes traditionally stocked for recreational fishing. We considered deviations from the species optimal growth and biotic community temperature ranges, as well as exceedances of its survival threshold. We found that future warming will shift suitable rainbow trout habitat in British Columbia to higher relief areas, with the no-mitigation scenario leading to a loss of 39 to 61% of total kilometres of suitable stream habitat. The moderate mitigation would dramatically reduce climate change effects, resulting in minor changes to the amount of suitable stream habitat (+ 2 to − 8% from current conditions). About half (41% to 53%) of the current range is retained under the moderate mitigation scenario, and much of this is close to population centres reliant on the ecosystem services provided by rainbow trout. Our analysis offers guidance for watersheds that might be prioritized for adaptation measures, e.g., stocked watersheds are projected to suffer large losses in suitable habitat under both scenarios. Our work shows the regional value of climate mitigation and how at-risk watersheds can be identified and targeted for management interventions. Our work provides a template for such assessments for other geographies and species. [ABSTRACT FROM AUTHOR]

Understanding why people do what they do is central to advancing equitable and sustainable futures. Yet, theories about human action are fragmented across many social science disciplines, each with its own jargon and implicit assumptions. This fragmentation has hindered theory integration and accessibility of theories relevant to a given challenge. We synthesized human action theories from across the humanities and social sciences. We developed eight underlying assumptions—metatheories—that reveal a fundamental organization of human action theories. We describe each metatheory and the challenges that it best elucidates (illustrated with climate change examples). No single metatheory addresses the full range of factors and problems; only one treats interactions between factors. Our synthesis will help researchers, policymakers, and practitioners gain a multifaceted understanding of human action. [ABSTRACT FROM AUTHOR]

Conservation policies have changed over time in response to changes in human and ecological drivers. The impacts of climate (and other) concurrent changes prompt consideration of further iterations for both conservation means and objectives. In this paper we bring together previous disparate literatures and apply them to the question of how to adapt conservation polices to suit an era of climate change impacts. Our approach is based on two assertions: (i) that the integration of specific natural and social science insights is essential for understanding and effectively responding to this challenge, and (ii) that in addition to adaptive conservation means (strategies), attention needs to be given to considering adaptive conservation objectives. Specifically, we convert a core set of natural and social science insights into analytical tools known as heuristics or rules of thumb. We then use the heuristics as a basis to offer a list of preliminary propositions that can help inform the development of new means and objectives. The propositions address key considerations including recalibrating management objectives, the role of disturbance in facilitating ecological transitions, and overarching topics relating to governance. The propositions are speculative, and so intended only to outline potential avenues for further empirical research and subsequent refinement. In the spirit of adaptation, we expect and welcome their revision. [Copyright &y& Elsevier]

Coastal environments are some of the most populated on Earth, with greater pressures projected in the future. Managing coastal systems requires the consideration of multiple uses, which both benefit from and threaten multiple ecosystem services. Thus understanding the cumulative impacts of human activities on coastal ecosystem services would seem fundamental to management, yet there is no widely accepted approach for assessing these. This study trials an approach for understanding the cumulative impacts of anthropogenic change, focusing on Tasman and Golden Bays, New Zealand. Using an expert elicitation procedure, we collected information on three aspects of cumulative impacts: the importance and magnitude of impacts by various activities and stressors on ecosystem services, and the causal processes of impact on ecosystem services. We assessed impacts to four ecosystem service benefits — fisheries, shellfish aquaculture, marine recreation and existence value of biodiversity—addressing three main research questions: (1) how severe are cumulative impacts on ecosystem services (correspondingly, what potential is there for restoration)?; (2) are threats evenly distributed across activities and stressors, or do a few threats dominate?; (3) do prominent activities mainly operate through direct stressors, or do they often exacerbate other impacts? We found (1) that despite high uncertainty in the threat posed by individual stressors and impacts, total cumulative impact is consistently severe for all four ecosystem services. (2) A subset of drivers and stressors pose important threats across the ecosystem services explored, including climate change, commercial fishing, sedimentation and pollution. (3) Climate change and commercial fishing contribute to prominent indirect impacts across ecosystem services by exacerbating regional impacts, namely sedimentation and pollution. The prevalence and magnitude of these indirect, networked impacts highlights the need for approaches like this to understand mechanisms of impact, in order to develop strategies to manage them. [ABSTRACT FROM AUTHOR]