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Climate change increases exposure and bioaccumulation of pollutants in marine organisms, posing substantial ecophysiological and ecotoxicological risks. Here, we applied a trophodynamic ecosystem model to examine the bioaccumulation of organic mercury (MeHg) and polychlorinated biphenyls (PCBs) in a Northeastern Pacific marine food web under climate change. We found largely heterogeneous sensitivity in climate-pollution impacts between chemicals and trophic groups. Concentration of MeHg and PCBs in top predators, including resident killer whales, is projected to be amplified by 8 and 3%, respectively, by 2100 under a high carbon emission scenario (Representative Concentration Pathway 8.5) relative to a no-climate change control scenario. However, the level of amplification increases with higher carbon emission scenario for MeHg, but decreases for PCBs. Such idiosyncratic responses are shaped by the differences in bioaccumulation pathways between MeHg and PCBs, and the modifications of food web dynamics between different levels of climate change. Climate-induced pollutant amplification in mid-trophic level predators (Chinook salmon) are projected to be higher (~10%) than killer whales. Overall, the predicted trophic magnification factor is ten-fold higher in MeHg than in PCBs under high CO 2 emissions. This contribution highlights the importance of understanding the interactions with anthropogenic organic pollutants in assessing climate risks on marine ecosystems.

Climate change is reshaping the way in which contaminants move through the global environment, in large part by changing the chemistry of the oceans and affecting the physiology, health, and feeding ecology of marine biota. Climate change-associated impacts on structure and function of marine food webs, with consequent changes in contaminant transport, fate, and effects, are likely to have significant repercussions to those human populations that rely on fisheries resources for food, recreation, or culture. Published studies on climate change-contaminant interactions with a focus on food web bioaccumulation were systematically reviewed to explore how climate change and ocean acidification may impact contaminant levels in marine food webs. We propose here a conceptual framework to illustrate the impacts of climate change on contaminant accumulation in marine food webs, as well as the downstream consequences for ecosystem goods and services. The potential impacts on social and economic security for coastal communities that depend on fisheries for food are discussed. Climate change-contaminant interactions may alter the bioaccumulation of two priority contaminant classes: the fat-soluble persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), as well as the protein-binding methylmercury (MeHg). These interactions include phenomena deemed to be either climate change dominant (i.e., climate change leads to an increase in contaminant exposure) or contaminant dominant (i.e., contamination leads to an increase in climate change susceptibility). We illustrate the pathways of climate change-contaminant interactions using case studies in the Northeastern Pacific Ocean. The important role of ecological and food web modeling to inform decision-making in managing ecological and human health risks of chemical pollutants contamination under climate change is also highlighted. Finally, we identify the need to develop integrated policies that manage the ecological and socioeconomic risk of greenhouse gases and marine pollutants., (© 2017 John Wiley & Sons Ltd.)

For decades, multiple anthropogenic stressors have threatened the Galápagos Islands. Widespread marine pollution such as oil spills, persistent organic pollutants, metals, and ocean plastic pollution has been linked to concerning changes in the ecophysiology and health of Galápagos species. Simultaneously, illegal, unreported, and unregulated fishing are reshaping the composition and structure of endemic and native Galápagos pelagic communities. In this novel review, we discuss the impact of anthropogenic pollutants and their associated ecotoxicological implications for Galápagos species in the face of climate change stressors. We emphasize the importance of considering fishing pressure and marine pollution, in combination with climate‐change impacts, when assessing the evolutionary fitness of species inhabiting the Galápagos. For example, the survival of endemic marine iguanas has been negatively affected by organic hydrocarbons introduced via oil spills, and endangered Galápagos sea lions exhibit detectable concentrations of DDT, triggering potential feminization effects and compromising the species' survival. During periods of ocean warming (El Niño events) when endemic species undergo nutritional stress, climate change may increase the vulnerability of these species to the impacts of pollutants, resulting in the species reaching its population tipping point. Marine plastics are emerging as a deleterious and widespread threat to endemic species. The Galápagos is treasured for its historical significance and its unparalleled living laboratory and display of evolutionary processes; however, this unique and iconic paradise will remain in jeopardy until multidisciplinary and comprehensive preventative management plans are put in place to mitigate and eliminate the effects of anthropogenic stressors facing the islands today. We present a critical analysis and synthesis of anthropogenic stressors with some progress from local and international institutional efforts and call to action more precautionary measures along with new management philosophies focused on understanding the processes of change through research to champion the conservation of the Galápagos. Integr Environ Assess Manag 2023;19:870–895. © 2022 SETAC Key Points: Ocean pollution, anthropogenic climate change, and fishing pressure (illegal, unregulated, and unreported fishing) are driving factors reshaping evolutionary processes and affecting marine biodiversity in the complex social–ecological systems of the UNESCO Global Heritage Site, Galápagos Islands.The combination of chemical pollution, marine debris, ocean plastics, climate change, and overfishing are conspiring to further contaminate marine life and food webs, which has obvious implications for ecosystems and the ocean, but also for the health of the islands' coastal communities.A proactive policy framework is essential to addressing and combating the multiple anthropogenic stressors, resulting from the intertwined nature of chemical pollution, climate change, and fishery pressure, across the biological and socioeconomic levels of organization in the Galápagos Islands.Although efforts for conservation and management are classic arenas to continue preserving the Galápagos Islands, an opportunity to frame solution‐oriented research to better understand the processes of change and conservation management remaking nature in the Anthropocene era is critical. [ABSTRACT FROM AUTHOR]

Environmental justice refers broadly to the distribution of environmental benefits and burdens, and the fair treatment and meaningful involvement of all people in environmental decision-making and legal frameworks. The field of environmental justice initially developed out of a concern for the disproportionate distribution and impacts of environmental pollution and hazardous waste disposal on groups that have been historically and structurally marginalized, including Black populations and socio-economically disadvantaged communities. More recent environmental justice scholarship has expanded geographically and focused on a broader set of environmental hazards and harms, such as climate change impacts, biodiversity and habitat loss, and ecosystem service declines. Yet, the impacts and distribution of environmental hazards and harms in the marine environment on coastal populations has received less attention in the environmental justice literature. This narrative review paper starts to address this gap through a focus on five main areas of environmental injustice in the ocean: 1) pollution and toxic wastes, 2) plastics and marine debris, 3) climate change, 4) ecosystem, biodiversity and ecosystem service degradation, and 5) fisheries declines. For each, we characterize the issue and root drivers, then examine social and distributional impacts. In the discussion, we explore how these environmental injustices are converging and interacting, cumulative, differentiated, and geographically distributed, and briefly examine solutions and future research directions. In conclusion, we call for greater and more explicit attention to environmental justice in ocean research and policy. [Display omitted] • There is a substantial and growing body of literature on environmental justice. • Yet, environmental justice issues in the oceans have received less attention. • Issues include pollution, plastics, climate change, ecosystem services and fisheries. • We examine the social and distributional impacts of these marine hazards and harms. • Environmental injustices in the ocean are growing, differentiated and converging. [ABSTRACT FROM AUTHOR]

Background: Extralimital observations of pinnipeds are important to understand the effects of changing climates on our oceans and the distribution of these species. The southern elephant seal (Mirounga leonina) is a known vagrant species that moves over long distances. We report three new records of M. leonina in interior freshwater tributaries of the Guayas River Estuary Basin (Gulf of Guayaquil) and northern coast of Ecuador between October 2017 and January 2018 during a cold episode of La Nina event in the southeastern Pacific. Results: The elephant seals were identified according to their large size (~ 5 m for adult and 2–3 m for juveniles/subadults), the head to neck size ratio, and the size and external morphology of the proboscis, which was used as a key trait to differentiate M. leonina from the Northern elephant seal (M. angustirostris). The observations of M. leonina in Ecuador highlight an extreme movement covering an assumed total distance of approximately 8000 km from the circumpolar region. The cold event "La Niña" with sea surface temperature anomalies ranging − 1.5 °C to − 0.5 °C in October 2017 likely triggered the extralimital movements of these animals. Conclusion: Recurring observations of M. leonina in the Guayaquil Gulf suggest the importance of this highly productive region and tropical estuarine-riverine habitats as temporary haulout sites for resting. These new findings indicate that vagrant individuals influenced by oceanographic events and eco-physiological processes are reaching this region more frequently than previously thought. [ABSTRACT FROM AUTHOR]