Declines of marine megafauna due to fisheries by-catch are thought to be mitigated by exclusion devices that release nontarget species. However, exclusion devices may instead conceal negative effects associated with by-catch caused by fisheries (i.e., unobserved or discarded by-catch with low postrelease survival or reproduction). We show that the decline of the endangered New Zealand (NZ) sea lion (Phocarctos hookeri) is linked to latent levels of by-catch occurring in sub-Antarctic trawl fisheries. Exclusion devices have been used since 2001 but have not slowed or reversed population decline. However, 35% of the variability in NZ sea lion pup production is explained by latent by-catch, and the population would increase without this factor. Our results indicate that exclusion devices can obscure rather than alleviate fishery impacts on marine megafauna.
In the latter part of the 20th century, fishery research expanded from its original biological base to include new areas, notably investigations of fishing-gear performance and fish-detection by sonar. The past 50 years have seen huge advances in technology and the combination of physical and biological insights in fishery research. Fishing-gear investigations initially focussed on the economics of commercial fishing, but in the 1970s energy consumption in fishing became a major issue. Thereafter, the objectives changed to support for fishery management through gear innovations and research, giving a better understanding of exploitation patterns. During this period, fishery acoustics advanced from crude beginnings in the 1960s to the powerful stock-assessment tool it is today. Progress in these fields has depended on multi-disciplinary research involving both the physical and biological sciences. There have been failures along the way, but there is now good understanding of how technology as well as science can make a positive contribution to fishery management. This essay describes these developments as seen from my personal involvement over the past half century. It concludes with some pointers to the future, and practical advice to young researchers considering a career in fishery research.
Iñupiaq, Yup'ik, and Cup'ik hunters in 14 Alaska Native communities described a rapidly changing marine environment in qualitative traditional knowledge interviews conducted over the course of a decade with 110 individuals. Based on their observations, sea ice conditions are the most notable change, with later freeze-up, thinner and less reliable ice, and earlier and more rapid break-up. Marine mammal populations in northern and western Alaska have been affected by changes in the physical environment, with alterations to migratory timing and routes, distribution, abundance, health, and behavior. Despite these changes, marine mammal populations in the region remain generally healthy and abundant. For hunters, access is the biggest challenge posed by changing conditions. Sea ice is less safe for travel, particularly for more southerly communities, making hunting more dangerous or impossible. Rapid break-up has reduced the time available for hunting amid broken ice in spring, formerly a dependable and preferred season. Social change also affects the ways in which hunting patterns change. Increased industrial development, for example, can also alter marine mammal distribution and reduce hunting opportunity. Reduced use of animal skins for clothing and other purposes has reduced demand. More powerful and reliable engines make day trips easier, reducing the time spent camping. An essential component of adjustment and adaptation to changing conditions is the retention of traditional values and the acquisition of new information to supplement traditional knowledge. Our findings are consistent with, and add detail to, what is known from previous traditional knowledge and scientific studies. The ways in which hunters gather new information and incorporate it into their existing understanding of the marine environment deserves further attention, both as a means of monitoring change and as a key aspect of adaptation. While the changes to date have been largely manageable, future prospects are unclear, as the effects of climate change are expected to continue in the region, and ecological change may accelerate. Social and regulatory change will continue to play a role in fostering or constraining the ability of hunters to adapt to the effects of climate change.
Marine social–ecological systems are constantly changing, and fishers who make a living from working the seas are continually adapting in response to different sources of variability. One main way in which fishers can adapt to ecosystem change is to change the fisheries they participate in. This acts to connect fisheries, creating interlinked networks of alternative sources of income for fishers. Here, we synthesize fisheries data and construct fisheries connectivity networks for all major ports in the US California Current Large Marine Ecosystem. Fisheries connectivity networks are comprised of nodes, which are fisheries, connected by edges, whose weights are proportional to the number of participating vessels. Fisheries connectivity networks identify central fisheries in the US California Current Large Marine Ecosystem, specifically Dungeness crab and Spiny Lobster, and systematic topological differences, e.g. in network resilience and modularity. These network metrics directly relate to the social vulnerability of coastal fishing communities, especially their sensitivity and capacity to adapt to perturbation. Ultimately, improving knowledge of fisheries connectivity is vital if policy makers are to create governance institutions that allow fishermen to adapt to environmental, technological and management change while at the same time enhancing the social and economic value of fisheries. In doing so, new policies that account for fisheries connectivity, will lead to improved sustainable fisheries management, and enhanced socioeconomic resilience of coastal communities.
The increasing economic power of East-Asian nations, new technologies, and demographic change in the Pacific Rim countries bring new opportunities for Pacific Islands Countries (PICs). The 21st century is often referred to as the “Pacific Century,” reflecting the rising economic and political importance of East Asian nations and trans-Pacific relationships. This report argues that the PICs can truly make the Pacific Century their own, by taking advantage of new opportunities that are already on the horizon. These developments may help offset the challenges the PICs are facing to achieve sustained high growth, which include extreme remoteness, small size, geographic dispersion, and environmental fragility that limit the range of economic activities where the PICs can be competitive. Indeed, many PICs have seen only very limited increases in per capita incomes over the past 25 years.
Pacific Possible assesses whether fully exploiting new economic opportunities and dealing effectively with major threats could lead to a significant acceleration of economic growth and improved standards of living over the next 25 years. Pacific Possible examines specific opportunities and risks for the PICs in seven selected areas. These include opportunities for increased incomes (tourism, knowledge economy, fisheries, deep sea mining, and labor mobility) as well as risks (climate change and disaster risks, noncommunicable diseases - NCDs) that, if not managed well, could undermine development gains. While Pacific Possible focuses on those economic opportunities that have the greatest potential to drive faster economic growth in the future, it is important to note that other economic activities such as agriculture, coastal fisheries and so forth will remain important sources of livelihoods for much of the population of the PICs and require continued attention by policy makers.
For each of the transformational opportunities, Pacific Possible develops an “opportunity scenario” that considers external developments (such as demographic developments or technological changes) as well as policy decisions that drive the opportunity. The “opportunity scenario” typically presents an ambitious, although realistic, outlook on what is possible. For each of the opportunities, we then estimate the achievable impact on per capita incomes, employment, and government revenue. Comparing this to “business-as-usual” projections, that typically re ect historical trends, gives us the additional income, employment, and government revenue that could be achieved if opportunities are fully exploited and adequate policy decisions taken and implemented.
The report covers 11 World Bank member countries in the Pacific (PIC11-Federated States of Micronesia, Fiji, Kiribati, the Marshall Islands, Palau, Papua New Guinea, Samoa, the Solomon Islands, Tonga, Tuvalu, and Vanuatu). Opportunities and risks discussed best describe the smaller PICs but are also valid for larger countries (Fiji, Papua New Guinea), although in these countries there are many more economic opportunities (for example, Lique ed Natural Gas in Papua New Guinea or niche manufacturing in Fiji) which are beyond the scope of Pacific Possible.
Citizen Science is an approach which involves members of the public in gathering scienti c data and, in more advanced cases, also involves them in the analysis of such data and in the design of scienti c research. Bene ts of this approach include enhancing monitoring capabilities, empowering citizens and increasing Ocean Literacy, which can itself lead to the development of environmentally-friendly behaviours. There is a long history of citizen participation in science as a general concept. However, the process of studying and understanding the best ways to develop, implement, and evaluate Citizen Science is just beginning and it has recently been proposed that the study of the process and outcomes of Citizen Science merits acknowledgement as a distinct discipline in its own right.
Considering the vastness of the ocean, the extensiveness of the world’s coastlines, and the diversity of habitats, communities and species, a full scienti c exploration and understanding of this realm requires intensive research and observation activities over time and space. Citizen Science is a potentially powerful tool for the generation of scienti c knowledge to a level that would not be possible for the scienti c community alone. Additionally, Citizen Science initiatives should be promoted because of their bene ts in creating awareness of the challenges facing the world’s ocean and increasing Ocean Literacy.
Responding to this, the European Marine Board convened a Working Group on Citizen Science, whose main aim was to provide new ideas and directions to further the development of Marine Citizen Science, with particular consideration for the European context.
This position paper introduces the concept and rationale of Citizen Science, in particular regarding its relationship to marine research. The paper then explores European experiences of Marine Citizen Science, presenting common factors of success for European initiatives as examples of good practice. The types of data amenable to Citizen Science are outlined, along with concerns and measures relating to ensuring the scienti c quality of those data. The paper further explores the social aspects of participation in Marine Citizen Science, outlining the societal bene ts in terms of impact and education. The current and potential future role of technology in Marine Citizen Science projects is also addressed including, the relationship between citizens and earth observations, and the relevance of progress in the area of unmanned observing systems. The paper nally presents proposals for the improved integration and management of Marine Citizen Science on a European scale. This leads to a detailed discussion on Marine Citizen Science informing Marine Policy, taking into account the requirements of the Aarhus Convention as well as the myriad of EU marine and environmental policies.
The paper concludes with the presentation of eight Strategic Action Areas for Marine Citizen Science in Europe (see summary below with details in Chapter 4). These action areas, which are aimed not only at the marine research community, but also at scientists from multiple disciplines (including non-marine), higher education institutions, funding bodies and policy makers, should together enable coherent future Europe-wide application of Marine Citizen Science for the bene t of all.
- The application of deicing road salts began in the 1940s and has increased drastically in regions where snow and ice removal is critical for transportation safety. The most commonly applied road salt is sodium chloride (NaCl). However, the increased costs of NaCl, its negative effects on human health, and the degradation of roadside habitats has driven transportation agencies to seek alternative road salts and organic additives to reduce the application rate of NaCl or increase its effectiveness. Few studies have examined the effects of NaCl in aquatic ecosystems, but none have explored the potential impacts of road salt alternatives or additives on aquatic food webs.
- We assessed the effects of three road salts (NaCl, MgCl2 and ClearLane™) and two road salts mixed with organic additives (GeoMelt™ and Magic Salt™) on food webs in experimental aquatic communities, with environmentally relevant concentrations, standardized by chloride concentration.
- We found that NaCl had few effects on aquatic communities. However, the microbial breakdown of organic additives initially reduced dissolved oxygen. Additionally, microbial activity likely transformed unusable phosphorus from the organic additives to usable phosphorus for algae, which increased algal growth. The increase in algal growth led to an increase in zooplankton abundance. Finally, MgCl2 – a common alternative to NaCl – reduced compositional differences of zooplankton, and at low concentrations increased the abundance of amphipods.
- Synthesis and applications. Our results indicate that alternative road salts (to NaCl), and road salt additives can alter the abundance and composition of organisms in freshwater food webs at multiple trophic levels, even at low concentrations. Consequently, road salt alternatives and additives might alter ecosystem function and ecosystem services. Therefore, transportation agencies should use caution in applying road salt alternatives and additives. A comprehensive investigation of road salt alternatives and road salt additives should be conducted before wide-scale use is implemented. Further research is also needed to determine the impacts of salt additives and alternatives on higher trophic levels, such as amphibians and fish.
Almost all of the world's fisheries overlap spatially and temporally with foraging seabirds, with impacts that range from food supplementation (through scavenging behind vessels), to resource competition and incidental mortality. The nature and extent of interactions between seabirds and fisheries vary, as does the level and efficacy of management and mitigation. Seabird dietary studies provide information on prey diversity and often identify species that are also caught in fisheries, providing evidence of linkages which can be used to improve ecosystem based management of fisheries. However, species identification of fish can be difficult with conventional dietary techniques. The black-browed albatross (Thalassarche melanophris) has a circumpolar distribution and has suffered major population declines due primarily to incidental mortality in fisheries. We use DNA metabarcoding of black-browed albatross scats to investigate their fish prey during the breeding season at six sites across their range, over two seasons. We identify the spatial and temporal diversity of fish in their diets and overlaps with fisheries operating in adjacent waters. Across all sites, 51 fish species from 33 families were identified, with 23 species contributing >10% of the proportion of samples or sequences at any site. There was extensive geographic variation but little inter-annual variability in fish species consumed. Several fish species that are not easily accessible to albatross, but are commercially harvested or by-caught, were detected in the albatross diet during the breeding season. This was particularly evident at the Falkland Islands and Iles Kerguelen where higher fishery catch amounts (or discard amounts where known) corresponded to higher occurrence of these species in diet samples. This study indicates ongoing interactions with fisheries through consumption of fishery discards, increasing the risk of seabird mortality. Breeding success was higher at sites where fisheries discards were detected in the diet, highlighting the need to minimize discarding to reduce impacts on the ecosystem. DNA metabarcoding provides a valuable non-invasive tool for assessing the fish prey of seabirds across broad geographic ranges. This provides an avenue for fishery resource managers to assess compliance of fisheries with discard policies and the level of interaction with scavenging seabirds.
Human interactions with sharks in the Northeast Pacific Ocean (NEP) have occurred for millennia but were largely limited to nearshore encounters as target and nontarget catch in fisheries. The arrival of Spanish explorers in the mid-1500s, followed by subsequent waves of explorers and colonizers from Europe and Russia, did little to change this relationship, until the mid-1800s. As technological advances conferred the ability to exploit marine fish further offshore and in deeper water, substantial fisheries developed and many of these encountered, and sometimes directly targeted, sharks. As these fisheries rose and fell with market demands and fluctuations in the abundance of target species, the collective consciousness of the nations fishing this region came to realize that adequate management plans with clear policy guidance rooted in conservation were crucial to sustaining both biodiversity and abundance of marine resources. With explicitly defined management regions governed by scientifically informed bodies that consider both societal and ecological needs, systems have been in place to manage and conserve marine species, including sharks, for over four decades now in the NEP. While policy evolution has largely limited directed fishing pressure as a threat for most shark species, bycatch is still a concern. Additionally, habitat degradation and destruction, ocean acidification, and global climate change are anticipated to fundamentally alter the ecosystems sharks are an integral part of in coming decades and centuries. Adequate conservation and management of sharks in the NEP, and around the world, moving into this period of uncertainty will rely upon comprehensive, integrated management of the ecosystem rooted in international coordination and cooperation. Far from being an unattainable goal, steps are being made each day to ‘move the needle’ in this direction—for the benefit of all.
Reduced sea ice has made the Arctic Ocean more accessible for vessel traffic. In turn, the heightened interest to better understand rapidly changing sea ice dynamics, ecosystems, and related ocean processes in the Arctic Ocean has led to closer interactions with and the need to avoid potential conflicts between scientific researchers and Indigenous coastal communities. In particular, researchers need to minimize spatial and temporal overlap of science activities with subsistence hunts as the Arctic is essential to Indigenous communities for their food security and cultural heritage. In this regard, a Community and Environmental Compliance Standard Operating Procedure (CECSOP) was recently developed for the R/V Sikuliaq, which is owned by the National Science Foundation and operated by the University of Alaska Fairbanks College of Fisheries and Ocean Sciences and is part of the University-National Oceanographic Laboratory System. The CECSOP was developed with input and guidance from Alaska Indigenous community groups, state and federal agencies, and sea-going scientists. Here the document's basic principles and procedures are described, as well as its utility in helping guide constructive discussions and interactions between scientific users of R/V Sikuliaq and subsistence hunting communities when research and subsistence hunt activities have spatial and temporal overlap. The CECSOP is a “living” document and subject to future modifications and improvements. It may serve as a model for other scientific, commercial and industrial vessel operators to ensure best practices between subsistence hunting communities and vessel operators in the Arctic.
Anthropogenic disturbances are altering the functioning and provisioning of marine ecosystem services, and as such, affect marine wildlife profoundly. A major problem in this context is resource competition between marine predators and fisheries. Marine protected areas (MPAs) can be a powerful tool to provide protection to predators and their prey; however, effective management strategies are required. A case study of African penguin conservation in South Africa was used to illustrate the benefits of embracing adaptive and dynamic management in the marine environment. The South African government plans to implement 22 new MPAs, which will maximise socio-economic benefits, while ensuring adequate ocean environmental protection. In Algoa Bay, the main purpose of the proposed MPA is to increase populations of the endangered African penguin Spheniscus demersus. We used the results of a seven-year experiment, in which purse-seine fisheries were closed around penguin colonies in that area, and concluded that the new MPA would provide a legal improvement to the current situation, but would not be sufficient to increase numbers of African penguin populations. For this, larger no-take zones are necessary when prey availability is low. At the moment, ongoing acoustic surveys could provide recommendations on prey availability to design flexible MPA boundaries. More advanced surveys will be necessary in the future to allow for the MPA's criteria to be adapted, and fully benefit penguins and the coastal community. As such, this study illustrates the usefulness of an adaptive and dynamic management approach for the conservation of marine resources and endangered top predators.
California’s policymakers, coastal managers, and communities increasingly recognize that the inevitable collision of sea level rise with certain coastal development trends—what some have termed the “coastal squeeze”—threatens California’s coast. In addition to reducing the availability of highly valued coastal access and recreation areas, the coastal squeeze carries the potential to degrade, destroy, or privatize the state’s shoreline and tidelands and the economic, cultural, and ecological benefits they provide.
These important public values and benefits associated with our coast are protected by the public trust doctrine, a legal doctrine that reflects the supreme importance of public values, resources, and uses in California’s coastal tidelands and submerged lands.1 Under the public trust doctrine, California has a duty to protect and sustain its coastal tidelands and submerged lands for public purposes ranging from navigation and commerce to recreation and conservation, as well as the authority to defend the public’s interests when they are at risk.
The public trust doctrine can function as an important legal tool for adapting the use of California’s coastal lands to ongoing changes. California will find strong legal support—rooted in long-standing precedents and principles of property law—for considering the anticipated effects of sea level rise and other climate change impacts on public trust resources and interests. The doctrine also provides a framework for effective adaptation of public and private activities in vulnerable areas. Yet complex and sometimes conflicting interpretations of the doctrine have limited its application.
To provide a clear interpretation of the public trust doctrine’s potential role in climate change adap- tation along California’s coast, the Center for Ocean Solutions convened a working group of public trust and coastal land use experts in October 2016. The working group members jointly authored the following consensus statement, which describes California’s duty and authority under the public trust doctrine and identifies opportunities for policymakers, coastal managers, and stakeholders to improve the governance and management of our coastal public trust resources and uses in light of sea level rise.
As coral reefs continue to decline worldwide, it becomes ever more necessary to understand the connectivity between coral populations to develop efficient management strategies facilitating survival and adaptation of coral reefs in the future. Orbicella faveolata is one of the most important reef-building corals in the Caribbean and has recently experienced severe population reductions. Here, we utilize a panel of nine microsatellite loci to evaluate the genetic structure of O. faveolata and to infer connectivity across ten sites spanning the wider Caribbean region. Populations are generally well-mixed throughout the basin (FST = 0.038), although notable patterns of substructure arise at local and regional scales. Eastern and western populations appear segregated with a genetic break around the Mona Passage in the north, as has been shown previously in other species; however, we find evidence for significant connectivity between Curaçao and Mexico, suggesting that the southern margin of this barrier is permeable to dispersal. Our results also identify a strong genetic break within the Mesoamerican Barrier Reef System associated with complex oceanographic patterns that promote larval retention in southern Belize. Additionally, the diverse genetic signature at Flower Garden Banks suggests its possible function as a downstream genetic sink. The findings reported here are relevant to the ongoing conservation efforts for this important and threatened species, and contribute to the growing understanding of large-scale coral reef connectivity throughout the wider Caribbean.
The biodiversity, ecosystem services and climate variability of the Antarctic continent and the Southern Ocean are major components of the whole Earth system. Antarctic ecosystems are driven more strongly by the physical environment than many other marine and terrestrial ecosystems. As a consequence, to understand ecological functioning, cross-disciplinary studies are especially important in Antarctic research. The conceptual study presented here is based on a workshop initiated by the Research Programme Antarctic Thresholds – Ecosystem Resilience and Adaptation of the Scientific Committee on Antarctic Research, which focussed on challenges in identifying and applying cross-disciplinary approaches in the Antarctic. Novel ideas and first steps in their implementation were clustered into eight themes. These ranged from scale problems, through risk maps, and organism/ecosystem responses to multiple environmental changes and evolutionary processes. Scaling models and data across different spatial and temporal scales were identified as an overarching challenge. Approaches to bridge gaps in Antarctic research programmes included multi-disciplinary monitoring, linking biomolecular findings and simulated physical environments, as well as integrative ecological modelling. The results of advanced cross-disciplinary approaches can contribute significantly to our knowledge of Antarctic and global ecosystem functioning, the consequences of climate change, and to global assessments that ultimately benefit humankind.
Economic development and environmental conservation are often seen as opposing forces in the arena of government policy-making. With more than 7 million people and a rich diversity of marine species and habitats, Hong Kong is an excellent case study to explore this dynamic. Despite anthropogenic impacts, Hong Kong still hosts more than 90 species of stony corals within a marine area of 1650 km2. This is remarkable in light of the global plight of coral reefs, which have been reduced by ~80% worldwide in recent decades. The Hong Kong Special Administrative Region has not been immune to this negative trend with an unfortunate track of marine environmental disasters and, as such, can be viewed a harbinger for the future trajectory of coral reefs worldwide. Yet, the story is not entirely negative. Hong Kong possesses key assets, including capable government environmental agencies and competitive research led by local universities, which can bring novel and promising approaches for coral biodiversity conservation in an urbanized context. To coordinate and assist conservation efforts in Hong Kong, we here identify and prioritize major management efforts and identify knowledge gaps for coral conservation based on updated coral biodiversity distribution and a current literature review. Specifically, we propose five priorities for the most positive impact on conservation efforts: (1) reconstruct environmental baselines and establish long-term monitoring of local coral communities, (2) enhance the management and protection of local coral habitats, (3) improve water quality, (4) gain an understanding of the genetic connectivity among local and distant coral communities, and finally, (5) establish an active restoration program for local coral species/communities. In order to build progressive and integrative management strategies for coral biodiversity conservation in Hong Kong, we suggest specific ways in which these priorities be addressed and encourage a fresh dialogue between the government, the public and academia.
Healthy marine and coastal ecosystems provide valuable services - from food security, resources for economic growth and recreation alongside tourism and coastline protection. Among the most productive ecosystems on the planet, oceans and coasts ensure the well-being for a growing global population, which is likely to rise to over nine billion by 2050. They regulate global climate and offer essential adaptation capacity.
The future role of ecosystems for human well-being depends increasingly on developing the capacity of countries to manage human uses and impacts in order to ensure their health and self-repairing capacity is not undermined. Central to a transformational response to decades of overfishing, pollution and unplanned urban development will be moving from sectoral marine and coastal management, to a joined approach that marries the seemingly competing interests for ocean and coastal resources and space, such as environment, tourism, fisheries and energy generation, within a robust framework and a spatial planning perspective. This is central to ensuring equitable access among diverse interests and users.
The ecosystem approach lays out a series of principles to guide management towards long-term sustainability of marine and coastal ecosystems. With this new guide on Marine and Coastal Ecosystem-Based Management (EBM), UNEP seeks to assist countries and communities to take steps towards making marine and coastal ecosystem-based management operational - from strategic planning to on-site implementation. It has three main sections:
- Making the case for EBM - Why and how is change necessary?
- Examining the core elements of EBM
- Moving towards EBM: Visioning - Planning - Implementation
The Guide outlines operational considerations in an accessible language, drawing upon practical experiences and lessons across the globe - from tropical coastlines to temperate estuaries and polar ocean ecosystems. An important message is that this is an incremental process and there are different paths toward EBM. Cross boundary considerations and working with neighbours and even countries far away will be an essential component.
The target audience of the Guide includes planners and decision-makers in local, national and regional governments and communities across a broad spectrum of interests and uses. The Guide is not a technical manual or textbook, rather it is an introduction to EBM principles and 'thinking', and provides an overview of core elements and pathways to getting started.
This guide is intended to complement UNEP's work, such as the Green Economy providing guidance on making changes in the way we interact with ecosystems, as well as the Blue Carbon Initiative, which explores the potential for mitigating climate change by investing and re-investing in healthy coastal ecosystems that capture and store carbon. Moreover, good EBM offers a valuable solution for harnessing marine and coastal ecosystems in adapting to climate change and other potential disasters.
It has been 20 years since two seminal publications about ecosystem services came out: an edited book by Gretchen Daily and an article in Nature by a group of ecologists and economists on the value of the world’s ecosystem services. Both of these have been very highly cited and kicked off an explosion of research, policy, and applications of the idea, including the establishment of this journal. This article traces the history leading up to these publications and the subsequent debates, research, institutions, policies, on-the-ground actions, and controversies they triggered. It also explores what we have learned during this period about the key issues: from definitions to classification to valuation, from integrated modelling to public participation and communication, and the evolution of institutions and governance innovation. Finally, it provides recommendations for the future. In particular, it points to the weakness of the mainstream economic approaches to valuation, growth, and development. It concludes that the substantial contributions of ecosystem services to the sustainable wellbeing of humans and the rest of nature should be at the core of the fundamental change needed in economic theory and practice if we are to achieve a societal transformation to a sustainable and desirable future.
In sunlit waters, photochemical alteration of dissolved organic carbon (DOC) impacts the microbial respiration of DOC to CO2. This coupled photochemical and biological degradation of DOC is especially critical for carbon budgets in the Arctic, where thawing permafrost soils increase opportunities for DOC oxidation to CO2 in surface waters, thereby reinforcing global warming. Here we show how and why sunlight exposure impacts microbial respiration of DOC draining permafrost soils. Sunlight significantly increases or decreases microbial respiration of DOC depending on whether photo-alteration produces or removes molecules that native microbial communities used prior to light exposure. Using high-resolution chemical and microbial approaches, we show that rates of DOC processing by microbes are likely governed by a combination of the abundance and lability of DOC exported from land to water and produced by photochemical processes, and the capacity and timescale that microbial communities have to adapt to metabolize photo-altered DOC.
2014 marked the sixth and most widespread mass bleaching event reported in the Northwestern Hawaiian Islands, home to the Papahānaumokuākea Marine National Monument (PMNM), the world’s second largest marine reserve. This event was associated with an unusual basin-scale warming in the North Pacific Ocean, with an unprecedented peak intensity of around 20°C-weeks of cumulative heat stress at Lisianksi Island. In situ bleaching surveys and satellite data were used to evaluate the relative importance of potential drivers of bleaching patterns in 2014, assess the subsequent morality and its effects on coral communities and 3D complexity, test for signs of regional acclimation, and investigate long-term change in heat stress in PMNM. Surveys conducted at four island/atoll (French Frigate Shoals, Lisianski Island, Pearl and Hermes Atoll, and Midway Atoll) showed that in 2014, percent bleaching varied considerably between islands/atolls and habitats (back reef/fore reef and depth), and was up to 91% in shallow habitats at Lisianski. The percent bleaching during the 2014 event was best explained by a combination of duration of heat stress measured by Coral Reef Watch’s satellite Degree Heating Week, relative community susceptibility (bleaching susceptibility score of each taxon * the taxon’s abundance relative to the total number of colonies), depth and region. Mean coral cover at permanent Lisianski monitoring sites decreased by 68% due to severe losses of Montipora dilatata complex, resulting in rapid reductions in habitat complexity. Spatial distribution of the 2014 bleaching was significantly different from the 2002 and 2004 bleaching events likely due to a combination of differences in heat stress and local acclimatization. Historical satellite data demonstrated heat stress in 2014 was unlike any previous event and that the exposure of corals to the bleaching-level heat stress has increased significantly in the northern PMNM since 1982, highlighting the increasing threat of climate change to reefs.
With the high rate of ecosystem change, effective systematic conservation planning must account for ongoing and imminent threats to biodiversity to ensure its persistence. Accordingly, guidance on appropriate conservation actions in the face of climate change has been accumulating. We review this guidance and bring together the key recommendations needed to successfully account for climate change impacts, relevant to the scale at which natural resource management is carried out. We discuss how the traditional conservation tools of protection and restoration need to be adjusted to be effective in the face of climate change. We highlight the conservation innovations such as moveable and temporary reserves, and Targeted Gene Flow. We build on recent work to provide critical advice for considering climate change in conservation planning. In particular, we discuss how stating explicit objectives related to climate change adaptation, quantifying uncertainty, and exploring trade-offs will better place conservation plans to meet objectives for multiple goals such as protection of species, ecosystems, geophysical diversity and ecological processes.