Marine plastic pollution is present in all oceans, including remote oceanic islands. Despite the increasing number of articles on plastic pollution in the last years, there is still a lack of studies in islands, that are biodiversity hotspots when compared to the surrounding ocean, and even other recognized highly biodiverse marine environments. Articles published in the peer reviewed literature (N = 20) were analysed according to the presence of macro (>5 mm) and microplastics (<5 mm) on beaches and the marine habitats immediately adjacent to 31 islands of the Atlantic Ocean and Caribbean Sea. The first articles date from the 1980s, but most were published in the 2000s. Articles on macroplastics were predominant in this review (N = 12). Beaches were the most studied environment, possibly due to easy access. The main focus of most articles was the spatial distribution of plastics associated with variables such as position of the beach in relation to wind and currents. Very few studies have analysed plastics colonization by organisms or the identification of persistent organic pollutants (POPs). Islands of the North/South Atlantic and Caribbean Sea were influenced by different sources of macroplastics, being marine-based sources (i.e., fishing activities) predominant in the Atlantic Ocean basin. On the other hand, in the Caribbean Sea, land-based sources were more common.
Resilience is a wide term that encompasses a variety of characteristics of different systems. The most common interpretation of resilience is the capacity of a system to absorb a change and reorganise to maintain its functions. This study explores the characteristics of resilience exhibited by a shellfish aquaculture-reliant coastal community in Kesennuma Bay, Japan, after the Great East Japan Earthquake, in relation to the principles of resilience as affected by local leadership. The community was greatly impacted by the tsunami and the Fukushima Daiichi Nuclear Power Plant meltdown in terms of ecological, social, economic damage. A local non-profit organisation (NPO) played a central role in the community's effort to respond to the devastation and reorganise to become functional again and maintain its structures. The leadership potential exhibited throughout the process of community recovery was the key factor in achieving high levels of collective action and a reorganisation of the community.
Protected areas not allowing extractive activities (here called fully protected area) are a spatially explicit conservation management tool commonly used to ensure populations persistence. This is achieved when an adequate fraction of a species' population spends most of its time within the boundaries of the protected area. Within a marine context, home ranges represent a tractable metric to provide guidance and evaluation of fully protected areas. We compiled peer-reviewed literature specific to the home ranges of finfishes and invertebrates of ecological and/or commercial importance in the Mediterranean Sea, and related this to the size of 184 Mediterranean fully protected areas. We also investigated the influence of fully protected areas size on fish density in contrast to fished areas with respect to home ranges. Home range estimations were available for 11 species (10 fishes and 1 lobster). The European spiny lobster Palinurus elephas had the smallest home range (0.0039 ± 0.0014 km2; mean ± 1 SE), while the painted comber Serranus scriba (1.1075 ± 0.2040 km2) had the largest. Approximately 25% of Mediterranean fully protected areas are larger than 2 times the size of the largest home range recorded. Fish densities were significantly higher when fully protected areas were larger than the home range, while no change in density occurred when home ranges were larger than fully protected areas. These results display a direct link between the effectiveness of fully protected areas and species' home range, suggesting that fully protected areas of at least 3.6 km2 may increase the density of local populations of these coastal marine species.
Submerged coral reefs (SCRs) are found on the continental shelves of the tropical regions of the world. Unlike shallow reefs, such submerged structures have been little studied in the world despite their ecological importance. We present the results of several explorations carried out between 2015 and 2017 in the Sistema Arrecifal Veracruzano National Park (SAVNP) and surrounding areas, which account for the presence of 18 SCRs both inside and outside the National Park. The location of these reefs was based on user information, literature and official documents. Through the use of echo sounder, the dimensions and morphological conformation of the reefs were identified. The protection of submerged coral reefs in the SAVPN is limited. They are not fully considered in the MPA creation decrees, and most of them are located in areas assigned to artisanal fisheries. Connectivity, fisheries, port activities and the lack of scientific information are issues to be attended by environmental authorities to guarantee the protection of these ecosystems.
The Hoi An World Heritage site in Vietnam has faced increasing coastal erosion as a result of both natural and anthropogenic causes since the 2010s. Main drivers are the construction of hydropower dams on the Vu Gia and Thu Bon Rivers, illegal sand mining in the South China Sea, and sea level rise along the Central Coast Vietnam. Coastal erosion affects the tourism attraction of this area. A challenge for both the national government and the local authorities is understanding the nature of the contemporary coastal erosion; this includes the beach erosion and tourism relationship. This study deals with the damage valuation of the beach erosion in relation to the tourism revenue based on the hedonic pricing method. Cua Dai beach of Hoi An is structured into 23 beach sectors along the shore, each of which shows a relative homogeny in physical characteristics, anthropogenic activities, and socioeconomics. The beach value is function of morphological variables such as beach width and distance to the city center, and tourism variables such as tourist area, coastal businesses, the number of hotels, and the number of hotel rooms. The two-stage least squares (2SLS) of the custom-log model is the most accurate approach. The total projected revenue losses are more than an estimated 29 million US dollars by 2040. The present values of the total annual revenue losses in 2020, 2030, and 2040 are about 29.6, 21.4, and 14 million US dollars, respectively, at an interest rate of 5%. The results suggest mitigation strategies and policy recommendations. The proposal includes improving the adaptation capacity to coastal erosion using innovative, smart, and wise solutions. Beach nourishment and coastal defense structures can be sustainable management tools combating coastal erosion only if the multicausal coastal processes are properly considered and a detailed cost–benefit analysis is performed.
The paper develops a production function for the Global Ocean Health Index (OHI) for 2013. Data from the Ocean Health Statistics, plus from the Human Development Index (HDI) for 151 countries are used. We employ two-stage regression model to conduct this evaluation. The tobit model, used to obtain the estimated dependent variable, results show Coastal Protection, Livelihoods and Economies, Tourism and Recreation, Iconic Species, Clean Water and Biodiversity, Food Provision, Artisanal Fisheries Opportunities, Natural Products, and Carbon Storage are significant variables. The rank regression in the second stage showed that HDI and Marine Protected Areas (MPAs) significantly influenced the predicted value of the OHI. Policy makers should note that biodiversity increases have the greatest effect on OHI, and its improvement is within reach of even the poorest country. Countries with varying levels of resource endowment may choose different techniques to improve OHI, but the implementation of MPAs should be priority.
This study was conducted in the fishing community of the Cabedelo municipality (NE Brazil, Paraíba) and characterized the socioeconomic profile of the fishers, their local ecological knowledge and their main usage of fish species. Overall, 80 fishers were interviewed. Snowball, direct observation, guided tours, free interviews and structured and semi-structured questionnaires were used for data collection, which occurred from December 2010 to June 2011 in fortnightly visits to the city of Cabedelo. Most fishers ranged from 36 to 45 years, with low education and low income levels, and approximately 87% fished in the municipality. At least 33 fish species were recorded as important for family consumption and trade. The most commonly caught fish families were Carangidae, Mugilidae, Lutjanidae and Scombridae. The fishes most used for commerce were Lutjanidae, Scombridae, and Serranidae. Fishers demonstrated a high knowledge about the temporal distribution of fishes and categorized them as “fishes of summer”, “fishes of winter” and “fishes around all year”; fishes' vertical distributions were categorized as either “bottom fish” or “water flower”. Fishers also classified eating habits, some types of behavior and reproduction of most exploited species. Fishermen's understanding of the fish stocks distribution and fish ecology is potentially imperative for scientific knowledge and future shared management plans.
This book will illustrate the current status, trends and effects of climate, natural disturbances and anthropogenic stressors on marine ecosystems. It shows how to integrate different management tools and models in an up-to-date, multidisciplinary approach to environmental management. Through several case studies, it provides a powerful framework for identifying management tools and their applications in coral reefs, fisheries, migratory species, marine islands and associated ecosystems such as mangroves and sea grass beds, including their ecosystem services, the threats to their sustainability, and the actions needed to protect them.
Disturbance of wildlife by ecotourism has become a major concern in the last decades. In the Mediterranean, sea-based tourism and related recreational activities are increasing rapidly, especially within marine protected areas (MPAs) hosting emblematic biodiversity. We investigated the impact of ecotourism in the Scandola MPA (UNESCO World Heritage Site, Corsica island), on the population of a conservation flagship, the Osprey Pandion haliaetus. Over the 37-year study period, tourists flow increased sharply. Osprey breeding performance initially increased, but then dropped for pairs nesting within the MPA compared to those breeding elsewhere in Corsica. We examined several hypotheses that could explain such reduction in breeding performance. Recent osprey breeding failures in the MPA are not caused by food scarcity. Using underwater fish surveys, we showed that fish consumed by ospreys were more numerous within the MPA. Focal observation at nests revealed that the overall number of boat passages within 250 m of osprey nests were three times higher inside the MPA compared to a control area. Elevated boat traffic significantly modified osprey time-budgets, by decreasing prey provisioning rate by males, and increasing time spent alarming and flying off the nest in females. This caused stress, and corticosterone levels in chick feathers were three times higher in high-traffic areas compared to places with lower touristic flow in Corsica, the Balearic Islands and Italy. Overall, our integrative, long-term study demonstrates the negative impact of sea-based ecotourism on the Corsican osprey population. This stresses the worldwide importance of rigorously implementing sustainable ecotourism, within well-enforced MPAs.
Exploring our planetary boundaries (i.e. the safe operating space for humanity) has demonstrated that we have already exceeded three of the 10 defined variables which support our wellbeing: the rate of biodiversity loss, the biogeochemical fluxes of nitrogen and climate change (Rockström et al., 2009; Steffen et al., 2015). Recently more than 15,000 international scientists have warned that humanity was exceeding the limits of the planet (Ripple et al., 2017). Similarly, in marine ecosystems, biogeochemical fluxes and biosphere integrity exceed their safe boundaries (Nash et al., 2017). Despite the uncertainties and criticisms of the methodologies applied (Montoya et al., 2018), those authors agree that “it would be unwise to drive the Earth System substantially away from a Holocene-like condition. A continuing trajectory away from the Holocene could lead, with an uncomfortably high probability, to a very different state of the Earth System, one that is likely to be much less hospitable to the development of human societies” ( Steffen et al., 2015).
Foundation species define the ecosystems they live in, but ecologists have often characterized dominant plants as foundational without supporting evidence. Giant kelp has long been considered a marine foundation species due to its complex structure and high productivity; however, there is little quantitative evidence to evaluate this. Here, we apply structural equation modelling to a 15-year time series of reef community data to evaluate how giant kelp affects the reef community. Although species richness was positively associated with giant kelp biomass, most direct paths did not involve giant kelp. Instead, the foundational qualities of giant kelp were driven mostly by indirect effects attributed to its dominant physical structure and associated engineering influence on the ecosystem, rather than by its use as food by invertebrates and fishes. Giant kelp structure has indirect effects because it shades out understorey algae that compete with sessile invertebrates. When released from competition, sessile species in turn increase the diversity of mobile predators. Sea urchin grazing effects could have been misinterpreted as kelp effects, because sea urchins can overgraze giant kelp, understorey algae and sessile invertebrates alike. Our results confirm the high diversity and biomass associated with kelp forests, but highlight how species interactions and habitat attributes can be misconstrued as direct consequences of a foundation species like giant kelp.
Polar oceans, though remote in location, are not immune to the accumulation of plastic debris. The present study, investigated for the first time, the abundance, distribution and composition of microplastics in sub-surface waters of the Arctic Central Basin. Microplastic sampling was carried out using the bow water system of icebreaker Oden (single depth: 8.5 m) and CTD rosette sampler (multiple depths: 8–4369 m). Potential microplastics were isolated and analysed using Fourier Transform Infrared Spectroscopy (FT-IR). Bow water sampling revealed that the median microplastic abundance in near surface waters of the Polar Mixed Layer (PML) was 0.7 particles m−3. Regarding the vertical distribution of microplastics in the ACB, microplastic abundance (particles m−3) in the different water masses was as follows: Polar Mixed Layer (0–375) > Deep and bottom waters (0–104) > Atlantic water (0–95) > Halocline i.e. Atlantic or Pacific (0–83).
Modern zoos and aquariums aspire to contribute significantly to biodiversity conservation and research. For example, conservation research is a key accreditation criterion of the Association of Zoos and Aquariums (AZA). However, no studies to date have quantified this contribution. We assessed the research productivity of 228 AZA members using scientific publications indexed in the ISI Web of Science (WoS) database between 1993 and 2013 (inclusive). AZA members published 5175 peer-reviewed manuscripts over this period, with publication output increasing over time. Most publications were in the zoology and veterinary science subject areas, and articles classified as “biodiversity conservation” by WoS averaged 7% of total publications annually. From regression analyses, AZA organizations with larger financial assets generally published more, but research-affiliated mission statements were also associated with increased publication output. A strong publication record indicates expertise and expands scientific knowledge, enhancing organizational credibility. Institutions aspiring for higher research productivity likely require a dedicated research focus and adequate institutional support through research funding and staffing. We recommend future work build on our results by exploring links between zoo and aquarium research productivity and conservation outcomes or uptake.
Excessive use of plastics in daily life and the inappropriate disposal of plastic products are severely affecting wildlife species in both coastal and aquatic environments. Birds are top-predators, exposed to all threats affecting their environments, making them ideal sentinel organisms for monitoring ecosystems change. We set a baseline assessment of the prevalence of marine plastic litter affecting multi-species populations of aquatic birds in southern Portugal. By examining 160 stomach contents from 8 species of aquatic birds, we show that 22.5% were affected by plastic debris. Plastic was found in Ciconia ciconia, Larus fuscus and L. michahellis. Ciconia ciconia ingested the highest amount (number of items and total mass) of plastic debris. Polydimethylsiloxane (PDMS, silicones) was the most abundant polymer and was recorded only in C. ciconia. Plastic ingestion baseline data are of crucial importance to evaluate changes through time and among regions and to define management and conservation strategies.
A principal role of marine protected areas (MPAs) is to mitigate the decline of biodiversity. A key part of this role is to reduce the effects of fisheries on bycatch of vulnerable species. Bycatch can have an impact on species by reducing population sizes, and an ecosystem-level impact through the significant removal of biomass and subsequent trophic changes. In this regard, it is crucial to refine methods for quantifying interactions between fisheries and bycatch species, and to manage these interactions spatially. A new method is presented for quantifying interactions between fisheries and bycatch species at high spatial and temporal resolutions. Temporally explicit species distribution models are used to examine temporal dynamics of fisheries and bycatch. This method is applied to Australia’s Eastern Tuna and Billfish Fishery to estimate interactions with seven principal bycatch species. The ability of MPAs to reduce bycatch is evaluated, and considerations are outlined for the spatial management of fishery-bycatch species interactions. Australia’s Commonwealth Marine Reserve Network had a minimal impact on bycatch reduction under both the 2012 proclaimed and the 2015 panel-recommended zonings. These results highlight the need for threats to marine biodiversity to be incorporated directly into design of MPAs, and for close scrutiny of assumptions that threats will be incidentally abated after MPAs have been proclaimed, or that off-reserve mechanisms will compensate for inadequacies of MPAs.
We present a framework for results-based management (RBM) of commercial fisheries. The core idea of RBM is to reduce micromanagement by delegating management responsibility to resource users. The RBM framework represents an industrial organization approach to co-management and comprises three defining processes, conducted by three independent “agents”: (i) an “authority” defines specific and measurable and achievable objectives (outcome targets, OTs) for the utilization of fisheries resources, (ii) resource user organizations (termed “operators”) take responsibility for achieving these OTs and provide documentation that (iii) allows independent “auditors” to evaluate the achievement of OTs. Using incentive mechanisms, notably deregulation, RBM grants operators the flexibility to develop and implement innovative and cost-effective ways to achieve OTs. The feasibility of implementing RBM in five European fisheries was investigated in cooperation with relevant stakeholders through artificial planning processes and computer simulations. The operators involved were enthusiastic, and new management plans were drafted based on the framework. These included socioeconomic OTs in addition to traditional stock objectives, encompassing an ecosystem approach. Several issues are in need of further research to consolidate the approach and prepare the ground for practical implementation, including: the specification of the legal and regulatory framework required to underpin RBM, details of transitional arrangements when shifting towards RBM (including cost-sharing) and the development of necessary organizational capacity for operators. Initially, we therefore envisage the framework being applied to high-value single-species fisheries, with a limited number of participants, which are adequately represented by a competent organization.
In this paper, I argue that we have at hand what is needed to provide scientific advice for ecosystem-based management of small pelagics and other species groups now. The ingredients for this advice are (i) large marine ecosystems as spatial management units; (ii) maintaining ecosystem productivity and exploiting at multispecies maximum yield as overarching management objectives; (iii) assessment of ecosystems by evaluating changes in primary productivity; (iv) an operational management procedure in which single-species catch proposals are adjusted to ecosystem productivity using a set of control rules. Inspection of historic landings for small pelagics and other small species in the Northeast Atlantic (ICES area) reveals that most likely fisheries exploitation does not, and never did, exceed system productivity in most LMEs and is therefore overall sustainable, although not necessarily for individual stocks.
Anthropogenic noise across the world's oceans threatens the ability of vocalizing marine species to communicate. Some species vocalize at key life stages or whilst foraging, and disruption to the acoustic habitat at these times could lead to adverse consequences at the population level. To investigate the risk of these impacts, we investigated the effect of vessel noise on the communication space of the Bryde's whale Balaenoptera edeni, an endangered species which vocalizes at low frequencies, and bigeye Pempheris adspersa, a nocturnal fish species which uses contact calls to maintain group cohesion while foraging. By combining long-term acoustic monitoring data with AIS vessel-tracking data and acoustic propagation modelling, the impact of vessel noise on their communication space was determined. Routine vessel passages cut down communication space by up to 61.5% for bigeyes and 87.4% for Bryde's whales. This influence of vessel noise on communication space exceeded natural variability for between 3.9 and 18.9% of the monitoring period. Additionally, during the closest point of approach of a large commercial vessel, <10 km from the listening station, the communication space of both species was reduced by a maximum of 99% compared to the ambient soundscape. These results suggest that vessel noise reduces communication space beyond the evolutionary context of these species and may have chronic effects on these populations. To combat this risk, we propose the application or extension of ship speed restrictions in ecologically significant areas, since our results indicate a reduction in sound source levels for vessels transiting at lower speeds.
Governability is an important concept in the political and environmental social sciences with increasing application to socio-ecological systems such as fisheries. Indeed, governability analyses of fisheries and related systems such as marine-protected areas have generated innovative ways to implement sustainability ideals. Yet, despite progress made, we argue that there remain limitations in current conceptions of governability that hinder further analytical development and use. By drawing on general systems theory—specifically cybernetics, control and feedback—we interrogate the conceptual foundations that underpin two key limitations: the need to incorporate the numerous variables that comprise a complex, holistic system into a singular assessment of governability, and the a priori separation of the governor and the governed that precludes analysis of a self-governing situation. We argue that by highlighting the reciprocal nature of a governor–governed relationship and the co-produced understanding of governing capacity and objects, a relational approach to governability is possible. This offers a clearer and more pragmatic understanding of how governors and fishers can make fisheries governable.
Marine Protected Areas (MPAs) are widely used as tools to maintain biodiversity, protect habitats and ensure that development is sustainable. If MPAs are to maintain their role into the future it is important for managers to understand how conditions at these sites may change as a result of climate change and other drivers, and this understanding needs to extend beyond temperature to a range of key ecosystem indicators. This case study demonstrates how spatially-aggregated model results for multiple variables can provide useful projections for MPA planners and managers. Conditions in European MPAs have been projected for the 2040s using unmitigated and globally managed scenarios of climate change and river management, and hence high and low emissions of greenhouse gases and riverborne nutrients. The results highlight the vulnerability of potential refuge sites in the north-west Mediterranean and the need for careful monitoring at MPAs to the north and west of the British Isles, which may be affected by changes in Atlantic circulation patterns. The projections also support the need for more MPAs in the eastern Mediterranean and Adriatic Sea, and can inform the selection of sites.