Reef sharks are vulnerable predators experiencing severe population declines mainly due to overexploitation. However, beyond direct exploitation, human activities can produce indirect or sub-lethal effects such as behavioral alterations. Such alterations are well known for terrestrial fauna but poorly documented for marine species. Using an extensive sampling of 367 stereo baited underwater videos systems, we show modifications in grey reef shark (Carcharhinus amblyrhynchos) occurrence and feeding behavior along a marked gradient of isolation from humans across the New Caledonian archipelago (South-Western Pacific). The probability of occurrence decreased by 68.9% between wilderness areas (more than 25 hours travel time from the capital city) and impacted areas while the few individuals occurring in impacted areas exhibited cautious behavior. We also show that only large no-entry reserves (above 150 km²) can protect the behavior of grey reef sharks found in the wilderness. Influencing the fitness, human linked behavioral alterations should be taken into account for management strategies to ensure the persistence of populations.
Seascape Ecology provides a comprehensive look at the state-of-the-science in the application of landscape ecology to the seas and provides guidance for future research priorities. The first book devoted exclusively to this rapidly emerging and increasingly important discipline, it is comprised of contributions from researchers at the forefront of seascape ecology working around the world. It presents the principles, concepts, methodology, and techniques informing seascape ecology and reports on the latest developments in the application of the approach to marine ecology and management.
Coastal cities continue to experience rapid urbanisation and population growth worldwide, linked to the diverse economic and social benefits flowing from proximity to the sea. Growing concern over human impacts upon coastal waters and global strategic goals for healthier cities requires that coastal cities develop innovative ways to inspire and empower communities to embrace and cherish city seascapes. Coastal city communities have much to gain from a healthier relationship with the sea. This paper proposes a collaborative community-led marine park concept that celebrates a city's connection to the marine environment, enhances sustainable economic prosperity and enables communities to participate in activities that deepen understanding, value, care and enjoyment of the city seascape. A city marine park (CMP) is not a marine protected area because it does not have biodiversity and heritage protection or ecosystem governance as a primary goal and does not aim to restrict human activities. A CMP enables city communities to collaborate towards a shared vision of elevated status and value for the city seascape. A CMP considers socio-economic and geographical context, including land-sea connectivity, and is integrated within a coastal city's strategic urban planning. This paper highlights core themes of a CMP and the diverse and wide-ranging benefits from coordinated activities that better connect the city community with its seascape. If co-created by the coastal city community and civic leaders, a CMP will form an enduring spatial nexus for progress toward healthy cities addressing multiple interlinked global sustainable development goals.
The aesthetic appreciation of natural places is one of the most fundamental ways in which people relate to their environment. It provides wellbeing, an opportunity for recreation and reflection, a sense of place, and cultural enrichment. It also motivates people to take care of natural places and to conserve them for current and future appreciation. Aesthetically valuable places also support significant economic activity. However, there is little guidance available to assist environmental managers and policy-makers to consider and integrate aesthetic values into decision-making processes. In this study, we present an approach for developing robust and practical indicators of aesthetic value to enable environmental managers to consider, assess and report on aesthetic condition and trend. We demonstrate its utility using the case of the Great Barrier Reef, a region currently undergoing significant social, economic and environmental change and an area formally protected, in part, for its aesthetic values. A qualitative scoping study with 30 key informants identified over 180 potential qualities contributing to reef aesthetics. We tested five for their utility in capturing key aspects of the coral reef aesthetic: (i) coral cover, (ii) coral pattern, (iii) coral topography, (iv) fish abundance, and (v) visibility. We asked 1,417 online Australians to aesthetically rate 50 out of 181 underwater coral reef images that varied in relation to these five attributes. Coral topography, fish abundance, and visibility were significantly correlated with aesthetic ratings, whilst coral cover and coral pattern were not. We also tested for demographic patterns in aesthetic ratings. Our pilot study has demonstrated that readily measurable characteristics of coral reefs can provide useful indicators of aesthetic quality, opening up opportunities for coral reef managers and policymakers to assess and track changes in aesthetics in ways that are relevant to the public. There is considerable scope to further advance capacity for monitoring and managing aesthetic values of coral reefs through additional research that resolves nuances in the meanings associated with aesthetics in coral reef settings.
As documented by the numerous publications that have appeared in recent years, plastic pollution of the environment and the effects on the respective ecosystems are currently one of the most intensely discussed issues in environmental science and in society at large. Of special concern are the effects of micro- and nano-sized plastics. A key issue in understanding the fate and potential effects of micro- and nano-sized plastics is their dynamic nature, as the size, shape, and charge of the particles change over time. Moreover, due to various biological processes, such as the aggregation of organic material and/or bacteria (“biofouling”), the density of plastic particles that settle in the sediments of aquatic ecosystems may be several orders of magnitudes higher than that in the surrounding waters. Consequently, the risk posed by plastic pollution to benthic fauna is considerably high. Nonetheless, the vast majority of studies examining the effects of microplastics have focused on pelagic organisms so far. We therefore conducted a comprehensive literature review to examine the impact of micro- and nano-sized plastics on benthic invertebrates, including the physical and chemical effects of leaching and the interactions of plastic particles with contaminants. Overall, 330 papers were reviewed for their fulfillment of different criteria (e.g., test species, plastic material, particle shape, particle size, exposure concentration, exposure route, assay type, assay duration), with 49 publications finally included in our survey. A comprehensive gap-analysis on the effects of plastic particles on benthic invertebrates revealed a wide variety of effects triggered by micro- and/or nano-sized plastics but also distinct differences regarding the plastic materials tested, the size fractions applied, the shape of the respective particles, and the exposure routes tested. Our review concludes with a discussion of the important research gaps concerning freshwater ecosystems and recommendations for future areas of research.
The 1988 Brazilian Federal Constitution established the promotion of environmental education (EE) as a Government’s public policy, which constitutes an important legal frame addressing this subject in Brazil, also considering the EE activities in coastal and marine protected areas (CMPAs). This chapter presents the legal frame, concepts, and potentialities of EE in CMPAs. Also, it highlights some experiences of EE in Brazilian PAs particularly to identify gaps, potentialities, and specificities for the development of coastal and marine environmental education (CMEE). Despite the conceptual and legal support for the development of EE activities in CMPAs, managers have a great difficulty to achieve these goals given the lack of funding, resources, personnel, and training, among other challenges that will be presented throughout this chapter. Thereby, environmental interpretation strategies assume great importance as well as citizen science initiatives and partnerships between public entities, civil society, and educational institutions. Considering this, it is of fundamental importance to encourage the social participation and diversity of partnerships. Also, it is necessary to test and improve CMEE methodologies in order to potentiate the teaching and learning process and to strength the democratic participation in the CMPAs management. In addition, it is clear that the CMEE needs financial independence, which could be supplied by the ecotourism in the CMPAs, but such initiatives are still incipient in Brazil.
For many species, reproductive failure may occur if abundance drops below critical Allee thresholds for successful breeding, in some cases impeding recovery. At the same time, extreme environmental events can cause catastrophic collapse in otherwise healthy populations. Understanding what natural processes and management strategies may allow for persistence and recovery of natural populations is critical in the face of expected climate change scenarios of increased environmental variability. Using a spatially explicit continuous-size fishery model with stochastic dispersal parameterized for abalone—a harvested species with sedentary adults and a dispersing larval phase—we investigated whether the establishment of a system of marine protected areas (MPAs) can prevent population collapse, compared with nonspatial management when populations are affected by mass mortality from environmental shocks and subject to Allee effects. We found that MPA networks dramatically reduced the risk of collapse following catastrophic events (75%–90% mortality), while populations often continued to decline in the absence of spatial protection. Similar resilience could be achieved by closing the fishery immediately following mass mortalities but would necessitate long periods without catch and therefore economic income. For species with Allee effects, the use of protected areas can ensure persistence following mass mortality events while maintaining ecosystem services during the recovery period.
The modern-day reinvigoration of individual Indigenous nations around the world is connected to broader simultaneous movements of Indigenous nationhood worldwide. The origins, implications, philosophies, and diversities of Indigenous resurgences and resistances continue to be discussed in the growing body of literature on Indigenous governance. This article builds on these discussions by focusing on the applied tools and strategies of Indigenous resurgence. In the context of the Pacific herring fishery in British Columbia, Canada, this research explores the strategies and tools used by three Indigenous coastal nations to apply pressure on the colonial government to abdicate its asserted authority over herring governance. Motivated by a time-honored relationship to herring, we discuss how these Indigenous nations have strategized to try to regain authority over herring governance to protect species and Indigenous access to the fishery. We then discuss this ocean-based resurgence in the context of global Indigenous movements for the reassertion of self-determining authority.
Mangrove forests provide valuable coastal protection from erosion, habitat for terrestrial and marine species, nursery grounds for commercial fisheries and are economically important for tourism. Galapagos’ mangroves usually grow directly on solid lava and fragmented rocky shores, thereby stabilizing the sediment and facilitating colonisation by other plants and many animals. However, until very recently, only inaccurate data described mangrove coverage and its distribution. We mapped mangroves using freely available Google Earth Very High Resolution images based on on-screen classification and compared this method to three semi-automatic classification algorithms. We also analysed mangrove change for the period 2004–2014. We obtained an area of 3657.1 ha of fringing mangrove that covers 35% of the coastline. Eighty percent of mangrove cover is found in Isabela island, and 90% in the western and central south-eastern bioregions. The overall accuracy of mangrove classification was 99.1% with a Kappa coefficient of 0.97 when validated with field data. On-screen digitization was significantly more accurate than other tested methods. From the semi-automated methods, Maximum Likelihood Classification with prior land-sea segmentation yielded the best results. During the 2004–2014 period, mangrove coverage increased 24% mainly by expansion of existing mangroves patches as opposed to generation of new patches. We estimate that mangrove cover and growth are inversely proportional to the geological age of the islands. However, many other factors like nutrients, currents or wave exposure protection might explain this pattern. The precise localization of mangrove cover across the Galapagos islands now enables documenting whether it is changing over time.
Several species found in the Bering Sea show significant spatial variation in total mercury concentrations ([THg]) longitudinally along the Aleutian Island chain. We assessed [THg] in other members of the Bering Sea food web to better understand the factors shaping regional differences. [THg] and stable carbon and nitrogen isotope ratios (δ15N and δ13C values) were measured in muscle tissue from 1052 fishes and cephalopods from parts of the Bering Sea and North Pacific Ocean adjacent to the Aleutian Islands. The spatial distribution of the samples enabled regional comparisons for 8 species of fish and one species of cephalopod. Four species showed higher mean length-standardized [THg] in the western Aleutian Islands management area. [THg] in yellow Irish lord were very different relative to those observed in other species and when included in multi-species analyses drove the overall regional trends in mean [THg]. Multi-species analyses excluding measurements for yellow Irish lord showed mean length-standardized [THg] was greater in the western Aleutian Islands than in the central Aleutian Islands management area. Linear regression of [THg] and δ15N values showed a significant and positive relationship across all species, varying between regions and across species. Isotopic space of all species was significantly different between the western Aleutian Islands and central Aleutian Islands, driven largely by δ13C values. Stable isotope values observed follow the same regional trend of lower trophic taxa reported in the literature, with significantly lower δ13C values in the western Aleutian Islands. We conclude that there are regional differences in carbon and nitrogen stable isotope ecology, as well as species-specific feeding ecology that influence [THg] dynamics in part of the marine food web along the Aleutian Island chain. These regional differences are likely contributors to the observed regional variations of [THg] in some high-level predators found in these regions.
The recent decline of the Arctic sea ice cover leads to an increasing number of vessels navigating through the Arctic shipping routes. Ballast water, essential for the vessel's safety during voyages and cargo transfers, however, is also considered one of the main vectors for transport and introduction of non-indigenous species. The aim of this paper is to investigate potential effects of the ballast water discharged in the main Arctic shipping routes on the local environment. For that a passive tracer was implemented in a fine resolution coupled ocean-sea ice model covering the entire Arctic and northern North Atlantic, to simulate the spread of the ballast water discharged based on release points along real ship positions from 2013. The model results showed that spring and summer were the seasons with the highest tendency for accumulation of ballast water tracer on the surface layers south of NovayaZemlyaand south of Spitsbergen, not only due to a higher number of vessels navigating in the area but also due to strong stratification. During winter and autumn, the tracer was mixed with and into deeper layers due to vertical convection. The simulated ballast water accumulation during spring and summer indicated that organisms, that survived the voyage in the ballast tanks, could establish a stable or growing population and eventually become invasive.
Interdisciplinary research is vital in addressing complex real-world problems. To understand how the scientific workforce is being engaged in the interdisciplinary research, it is important to track the involvement of different research fields over time and the grants that drive the research endeavour. Unfortunately, there has been very little work in this understanding of interdisciplinary research and grant success. In this paper, we analysed the contribution of different disciplines within multidisciplinary research that secured grants. We tracked these contributions over a 10-year period to understand how different research fields evolved over time and played roles in interdisciplinary grant success. We followed a basic statistical approach and proposed a network-based approach to understand relative participation of different disciplines. We found disparities within different disciplines which showed that only few research fields contributed more in the interdisciplinary research grant success.
Deep-sea mining (DSM) may become a significant stressor on the marine environment. The DSM industry should demonstrate transparently its commitment to preventing serious harm to the environment by complying with legal requirements, using environmental good practice, and minimizing environmental impacts. Here existing environmental management approaches relevant to DSM that can be used to improve performance are identified and detailed. DSM is still predominantly in the planning stage and will face some unique challenges but there is considerable environmental management experience in existing related industries. International good practice has been suggested for DSM by bodies such as the Pacific Community and the International Marine Minerals Society. The inherent uncertainty in DSM presents challenges, but it can be addressed by collection of environmental information, area-based/spatial management, the precautionary approach and adaptive management. Tools exist for regional and strategic management, which have already begun to be introduced by the International Seabed Authority, for example in the Clarion-Clipperton Zone. Project specific environmental management, through environmental impact assessment, baseline assessment, monitoring, mitigation and environmental management planning, will be critical to identify and reduce potential impacts. In addition, extractive companies’ internal management may be optimised to improve performance by emphasising sustainability at a high level in the company, improving transparency and reporting and introducing environmental management systems. The DSM industry and its regulators have the potential to select and optimize recognised and documented effective practices and adapt them, greatly improving the environmental performance of this new industry.
The study presents the first systematic review of the existing literature on Arctic ES. Applying the Search, Appraisal, Synthesis and Analysis (SALSA) and snowballing methods and three selection criteria, 33 publications were sourced, including peer-reviewed articles, policy papers and scientific reports, and their content synthesised using the thematic analysis method. Five key themes were identified: (1) general discussion of Arctic ES, (2) Arctic social-ecological systems, (3) ES valuation, (4) ES synergies and/or trade-offs, and (5) integrating the ES perspective into management. The meta-synthesis of the literature reveals that the ES concept is increasingly being applied in the Arctic context in all five themes, but there remain large knowledge gaps concerning mapping, assessment, economic valuation, analysis of synergies, trade-offs, and underlying mechanisms, and the social effects of ES changes. Even though ES are discussed in most publications as being relevant for policy, there are few practical examples of its direct application to management. The study concludes that more primary studies of Arctic ES are needed on all of the main themes as well as governance initiatives to move Arctic ES research from theory to practice.
Computer vision and image processing approaches for automatic underwater fish detection are gaining attention of marine scientists as quicker and low-cost methods for estimating fish biomass and assemblage in oceans and fresh water bodies. However, the main challenge that is encountered in unconstrained underwater imagery is poor luminosity, turbidity, background confusion and foreground camouflage that make conventional approaches compromise on their performance due to missed detections or high false alarm rates. Gaussian Mixture Modelling is a powerful approach to segment foreground fish from the background objects through learning the background pixel distribution. In this paper, we present an algorithm based on Gaussian Mixture Models together with Pixel-Wise Posteriors for fish detection in complex background scenarios. We report the results of our method on the benchmark Complex Background dataset that is extracted from Fish4Knowledge repository. Our proposed method yields an F-score of 84.3%, which is the highest score reported so far on the aforementioned dataset for detecting fish in an unconstrained environment.
Understanding processes that drive community recovery are needed to predict ecosystem trajectories and manage for impacts under increasing global threats. Yet, the quantification of community recovery in coral reefs has been challenging owing to a paucity of long-term ecological data and high frequency of disturbances. Here we investigate community re-assembly and the bio-physical drivers that determine the capacity of coral reefs to recover following the 1998 bleaching event, using long-term monitoring data across four habitats in Palau. Our study documents that the time needed for coral reefs to recover from bleaching disturbance to coral-dominated state in disturbance-free regimes is at least 9–12 years. Importantly, we show that reefs in two habitats achieve relative stability to a climax community state within that time frame. We then investigated the direct and indirect effects of drivers on the rate of recovery of four dominant coral groups using a structural equation modelling approach. While the rates of recovery differed among coral groups, we found that larval connectivity and juvenile coral density were prominent drivers of recovery for fast growing Acropora but not for the other three groups. Competitive algae and parrotfish had negative and positive effects on coral recovery in general, whereas wave exposure had variable effects related to coral morphology. Overall, the time needed for community re-assembly is habitat specific and drivers of recovery are taxa specific, considerations that require incorporation into planning for ecosystem management under climate change.
Fisheries management interventions that protect certain species by redistributing fishing effort may generate unintended consequences for other species. In the California drift gillnet fishery for swordfish and sharks, a large spatial closure was implemented in 2001 to protect endangered leatherback turtles, which limited fishing effort to the Southern California Bight. Leatherback bycatch has since decreased, but the effects on other species have not been comprehensively examined. Here, we explore the effects of this closure on the community catch composition in the fishery and find that other protected species may have benefited, while catch per unit effort of major target species increased or was not significantly affected over the long term. However, a time-series analysis reveals that changes in catch trends across twenty species began at least five years before the closure was implemented, suggesting that previous regulatory measures or other drivers may also contribute to these trends. These results highlight the importance of comprehensive approaches that include the historical context when evaluating management outcomes.
This article traces the emergence of the ‘fisheries crime’ concept from its national Nordic roots through its introduction to, and subsequent acceptance within, the international political arena. The centrality of the associated law enforcement approach is underscored and key international processes aimed at addressing transnational organised crime in the international fishing sector are discussed. The importance of cooperation both domestically, amongst relevant government agencies, and across borders, at a region and global level, in this regard is highlighted
Creativity and playfulness are important skills that educators use to promote environmental awareness and changes in beliefs, attitudes, and values. The production of reusable and easily available didactic materials can assist in this process. The purpose of this chapter is to present some teaching and learning didactic materials developed in Brazil for different marine and coastal environmental education activities. We will present some examples of materials produced for interpretive trails, as well as books, guides, folders, radio programs, games, and materials for exhibitions. Also, we will reflect upon the necessity of enhancing the dissemination and sharing of these materials among Brazilian environmental educators as well as their proper evaluation.