Increasing multi-hazard climate risk and financial and health impacts on northern homeowners.

Currently, more than half of the world's human population lives in urban areas, which are increasingly affected by climate hazards. Little is known about how multi-hazard environments affect people, especially those living in urban areas in northern latitudes. This study surveyed homeowners in Anchorage and Fairbanks, USA, Alaska's largest urban centers, to measure individual risk perceptions, mitigation response, and damages related to wildfire, surface ice hazards, and permafrost thaw. Up to one third of residents reported being affected by all three hazards, with surface ice hazards being the most widely distributed, related to an estimated $25 million in annual damages. Behavioral risk response, policy recommendations for rapidly changing urban environments, and the challenges to local governments in mitigation efforts are discussed.

Global gateways as telecoupled human and natural systems: The emerging case of the Bering Strait.

Numerous narrow marine passages around the world serve as essential gateways for the transportation of goods, the movement of people, and the migration of fish and wildlife. These global gateways facilitate human-nature interactions across distant regions. The socioeconomic and environmental interactions among distant coupled human and natural systems affect the sustainability of global gateways in complex ways. However, the assessment and analysis of global gateways are scattered and fragmented. To fill this knowledge gap, we frame global gateways as telecoupled human and natural systems using an emerging global gateway, the Bering Strait, as a demonstration. We examine how three telecoupling processes (tourism, vessel traffic, and natural resource development) impact and are impacted by the coupled human and natural system of the Bering Strait Region. Given that global gateways share many similarities, our analysis of the Bering Strait Region provides a foundation for the assessment of other telecoupled global gateways.

Small sight-Big might: Economic impact of bird tourism shows opportunities for rural communities and biodiversity conservation.

Birdwatching is considered one of the fastest growing nature-based tourism sectors in the world. Tourists who identify as birdwatchers tend to be well-educated and wealthy travellers with a specific interest in the places they visit. Birdwatchers can bring economic resources to remote communities diversifying their economies and contribute to biodiversity conservation in areas of bird habitat with global significance. Alaska plays a critical role in understanding the link between bird conservation and bird tourism as it supports the world's largest concentration of shorebirds and is a global breeding hotspot for hundreds of migratory species, including many species of conservation concern for their decline across their ranges. Alaska is also a global destination for birders due to the large congregations of birds that occur during the spring, summer and fall seasons. Despite its global importance, relatively little information exists on the significance of bird tourism in Alaska or on opportunities for community development that align with conservation. This study used ebird data to look at trends in Alaska birdwatching and applied existing information from the Alaska Visitor Statistics Program to estimate visitor expenditures and the impact of that spending on Alaska's regional economies. In 2016, nearly 300,000 birdwatchers visited Alaska and spent $378 million, supporting approximately 4,000 jobs. The study describes bird tourism's contributions to local jobs and income in remote rural and urban economies and discusses opportunities for developing and expanding the nature-based tourism sector. The study points toward the importance of partnering with rural communities and landowners to advance both economic opportunities and biodiversity conservation actions. The need for new data collection addressing niche market development and economic diversification is also discussed.

Non-stationary and interactive effects of climate and competition on pink salmon productivity.

Pacific salmon (Oncorhynchus spp.) are exposed to increased environmental change and multiple human stressors. To anticipate future impacts of global change and to improve sustainable resource management, it is critical to understand how wild salmon populations respond to stressors associated with human-caused changes such as climate warming and ocean acidification, as well as competition in the ocean, which is intensified by the large-scale production and release of hatchery reared salmon. Pink salmon (O. gorbuscha) are a keystone species in the North Pacific Ocean and support highly valuable commercial fisheries. We investigated the joint effects of changes in ocean conditions and salmon abundances on the productivity of wild pink salmon. Our analysis focused on Prince William Sound in Alaska, because the region accounts for ~50% of the global production of hatchery pink salmon with local hatcheries releasing 600-700 million pink salmon fry annually. Using 60 years of data on wild pink salmon abundances, hatchery releases, and ecological conditions in the ocean, we find evidence that hatchery pink salmon releases negatively affect wild pink salmon productivity, likely through competition between wild and hatchery juveniles in nearshore marine habitats. We find no evidence for effects of ocean acidification on pink salmon productivity. However, a change in the leading mode of North Pacific climate in 1988-1989 weakened the temperature-productivity relationship and altered the strength of intraspecific density dependence. Therefore, our results suggest non-stationary (i.e., time varying) and interactive effects of ocean climate and competition on pink salmon productivity. Our findings further highlight the need for salmon management to consider potential adverse effects of large-scale hatchery production within the context of ocean change.

Quantifying expert opinion with discrete choice models: Invasive elodea's influence on Alaska salmonids.

Scientific evidence should inform environmental policy, but rapid environmental change brings high ecological uncertainty and associated barriers to the science-management dialogue. Biological invasions of aquatic plants are a worldwide problem with uncertain ecological and economic consequences. We demonstrate that the discrete choice method (DCM) can serve as a structured expert elicitation alternative to quantify expert opinion across a range of possible but uncertain environmental outcomes. DCM is widely applied in the social sciences to better understand and predict human preferences and trade-offs. Here we apply it to Alaska's first submersed invasive aquatic freshwater plant, Elodea spp. (elodea), and its unknown effects on salmonids. While little is known about interactions between elodea and salmonids, ecological research suggests that aquatic plant invasions can have positive and negative, as well as direct and indirect, effects on fish. We use DCM to design hypothetical salmonid habitat scenarios describing elodea's possible effect on critical environmental conditions for salmonids: prey abundance, dissolved oxygen, and vegetation cover. We then observe how experts choose between scenarios that they believe could support persistent salmonid populations in elodea-invaded salmonid habitat. We quantify the relative importance of habitat characteristics that influence expert choice and investigate how experts trade off between habitat characteristics. We take advantage of Bayesian techniques to estimate discrete choice models for individual experts and to simulate expert opinion for specific environmental management situations. We discuss possible applications and advantages of the DCM approach for expert elicitation in the ecological context. We end with methodological questions for future research.

Hitchhikers on floats to Arctic freshwater: Private aviation and recreation loss from aquatic invasion.

This study of aviation-related recreation loss shows that a survey primarily aimed at collecting information on invasive species' pathways can also be used to estimate changes in pathway-related ecosystem services. We present a case study for Elodea spp. (elodea), Alaska's first known aquatic invasive plant, by combining respondents' stated pre-invasion actual flights with stated post-invasion contingent behavior, plane operating costs, and site quality data. We asked pilots about the extent of continued flights should destinations become invaded and inhibit flight safety. We estimate a recreation demand model where the lost trip value to the average floatplane pilot whose destination is an elodea-invaded lake is US$185 (95 % CI $157, $211). Estimates of ecosystem damages incurred by private actors responsible for transmitting invaders can nudge actors to change behavior and inform adaptive ecosystem management. The policy and modeling implications of quantifying such damages and integration into more complex models are discussed.