Literature Library

Currently indexing 7643 titles

Plastics Derived From Derelict Fishing Gear in the Arctic: Looking at Sustainable Fisheries for a Strategy of Mitigation, Remediation and Prevention in Iceland and Alaska

Armstrong NS. Plastics Derived From Derelict Fishing Gear in the Arctic: Looking at Sustainable Fisheries for a Strategy of Mitigation, Remediation and Prevention in Iceland and Alaska. Claremont: Pitzer College; 2020. Available from: https://scholarship.claremont.edu/pitzer_theses/95
Freely available?: 
Yes
Summary available?: 
No
Type: Thesis

Marine plastics are not just a problem, they are a silent, sinister epidemic. Marine plastics are the largest economic and ecological threat to our marine ecosystems, particularly marine plastics derived from lost and or discarded fishing gear, which affects sensitive marine communities, the chemical composition of the ocean water, and the physical makeup of the seafloor. With 6.4 million tons of marine debris entering our oceans annually, a third of which is lost fishing gear, it is estimated that, by weight, in 2050 there will be an accumulation of more plastic than fish in the ocean (Heath, 2018; Wilcox, 2015).

Marine litter derived from plastic fishing gear, primarily passive gear, when lost in the ocean causes a series of consequences to the marine ecosystem, that of which increases when there are high concentrations of fishing activity in the geographic area. Arctic countries have some of the most abundant fisheries, that of which is projected to increase due to anthropogenic climate change. In the context of climate change affecting the Arctic ecosystem, in this thesis, we will review the consequences of plastics derived from fishing gear for the Arctic marine ecosystem, estimate the potential influx of derelict gear plastics originating from data obtained in Alaska and Iceland, and then confidently present effective forms of remediation, prevention, and mitigation strategized from models of sustainable fisheries to resolve the ramifications of lost and or discarded gear in Arctic communities.

Links and Trade-Offs between Fisheries and Environmental Protection in Relation to the Sustainable Development Goals in Thailand

Sampantamit T, Ho L, Van Echelpoel W, Lachat C, Goethals P. Links and Trade-Offs between Fisheries and Environmental Protection in Relation to the Sustainable Development Goals in Thailand. Water [Internet]. 2020 ;12(2):399. Available from: https://www.mdpi.com/2073-4441/12/2/399
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

The fisheries sector significantly contributes to global food security, nutrition, and livelihood of people. Its importance for economic benefits, healthy diets, and nutrition, and achieving sustainable food systems is highlighted by several Sustainable Development Goals (SDGs), i.e., SDG 1 (No Poverty), SDG 2 (Zero Hunger), and SDG 14 (Life Below Water). However, due to unprecedented population levels, the contribution of the fisheries sector to fulfills these roles is challenging, particularly given additional concerns regarding environmental well-being and sustainability. From this perspective, this study aims to identify the links and trade-offs between the development of this sector and the environmental sustainability in Thailand via a critical analysis of their trends, current ecological impacts, and more importantly, their contributions to several individual SDGs. A time-series of Thailand’s fisheries production from 1995 to 2015 indicates a recent reduction from around 3.0 million tons in 1995 to 1.5 million tons in 2015 of wild fish and shellfish from marine and freshwater habitats. The maximum sustainable yield of these species has been exceeded. Conversely, Thailand’s aquaculture production has continued to grow over the last decade, resulting in a reduction of mangrove forest area, wild fish stocks, and water quality. While capture fisheries and aquaculture production significantly contribute to several SDG targets, there are potential trade-offs between their development and the achievement of SDGs within the planet dimension, i.e., SDG 6 (Clean Water and Sanitation), SDG 12 (Responsible Consumption and Production), SDG 13 (Climate Action), SDG 14, and SDG 15 (Life on Land). On the one hand, the mitigation of overfishing will be beneficial for the targets of SDG 14, leading to more sustainable resource management. On the other hand, it might cause a decrease in the volume of marine catches and economic and social profits. We conclude that the SDGs can serve as a framework for both policymakers and industrial workers to monitor and compromise on regulations that will optimize productivity in the context of sustainable development.

Foundation and Development of the Economic Interest of the United States in the Arctic Ocean in the Age of Global Warming

Fisher K. Foundation and Development of the Economic Interest of the United States in the Arctic Ocean in the Age of Global Warming. Ocean and Coastal Law Journal [Internet]. 2020 ;25(1). Available from: https://digitalcommons.mainelaw.maine.edu/oclj/vol25/iss1/5
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

The United States’ sustained economic and geopolitical interest in the Arctic is dependent on Congressional funding and Executive support for icebreaking vessels and improved infrastructure in United States arctic territory. The United States has an interest in the Arctic and it is demonstrated by The Arctic Research and Policy Act of 1984 (amended 1990). Through the Act, the United States initiated research and policy development, with the supposition of potential economic benefits in the future. Due to verifiable and anticipated changes in ice density in the Arctic, the region is accessible like never before, and international competition for natural resources and commercial shipping lanes in the Arctic offer enormous economic benefits. The United States is woefully behind its international competitors due to a small and decrepit fleet of icebreaking vessels and crumbling arctic infrastructure. In examining The Arctic Research and Policy Act of 1984 and multiple Arctic Strategy Plans that were published by federal agencies operating in the Arctic, it is clear—attention from Congress and the Executive must be redirected towards advancement. The first step to advancing the United States interest in the Arctic is by funding and procuring icebreaking vessels and improving arctic territory infrastructure.

Perception of Management Success in the Florida Keys National Marine Sanctuary: A Comparative Analysis Between Residents and Visitors

Quenée CTina. Perception of Management Success in the Florida Keys National Marine Sanctuary: A Comparative Analysis Between Residents and Visitors. Miami: University of Miami; 2019. Available from: https://scholarlyrepository.miami.edu/oa_theses/796
Freely available?: 
Yes
Summary available?: 
No
Type: Thesis

The Florida Keys National Marine Sanctuary is a multiple-use marine protected area with a history of tension between management entities and local stakeholders. At the root of the issues are differences in the definition of “successful management” between these two stakeholder groups and recent administrative vacancies within the Sanctuary’s management staff have made it difficult for the Sanctuary to update its management plan. This study surveyed two primary stakeholder groups in the Florida Keys in order to gain understanding of their perceptions of successful management. A comprehensive intercept survey detailing various management objectives was presented to participants in person using tablets and targeted emails over a period of five months. Results found that residency status was not the primary parameter influencing perception of management success, and that rather industry affiliation was strongly linked with views on management success. Significant differences between residents and visitors did exist when perception of threats to the Sanctuary was analyzed, indicating that those groups could benefit from targeted outreach and education ahead of changes to the management plan of the Florida Keys National Marine Sanctuary.

A Survey of Single-use Plastic Foodware Ordinances of the San Francisco Bay Region

Slafter C. A Survey of Single-use Plastic Foodware Ordinances of the San Francisco Bay Region. San Francisco: University of San Francisco; 2019. Available from: https://repository.usfca.edu/capstone/974
Freely available?: 
Yes
Summary available?: 
No
Type: Thesis

Municipal jurisdictions in the San Francisco Bay Region (SFBR) are passing comprehensive single-use plastic (SUP) foodware ordinances in response to growing public pressure, and a California mandate to achieve zero waste. SUP foodware items have become an issue of concern because they are readily available in the restaurant industry, and are regularly among the top-ten pollutants collected during beach cleanups. SUP foodware items pose a danger to marine wildlife and contribute to rising carbon dioxide (CO2) emissions. Policy makers in the SFBR are creating local ordinances that regulate the distribution and use of a variety of SUP foodware items. SUP ordinances are a new type of regulation and to help future policy makers better understand these regulations, a survey of all 108 SFBR municipal codes was conducted to identify the various types of SUP ordinances, and to identify and compare key ordinance characteristics. The results of the survey and analysis were: 45 (41.67%) municipalities do not have a SUP foodware ordinance, 52 (48.15%) have a polystyrene ordinance, four (3.70%) have a polystyrene and straw ordinance, and seven (6.48%) have a comprehensive SUP ordinance. Additional results were: municipalities that passed comprehensive SUP ordinances met the requirements of the California Environmental Quality Act (CEQA), ordinance language varied between municipalities, municipalities varied on what foodware items were regulated and how, and municipalities varied only slightly on what ordinance exemptions were provided. The identified variations were expected without the guidance of state-wide legislation or a regional model ordinance. Variations between ordinances may lead to regional consumer and food vendor confusion but more data on the environmental and fiscal impact of these ordinances should be collected before state-wide legislation or a model ordinance is developed.

Users’ perceptions and satisfaction as indicators for sustainable beach management

Brščić K, Šugar T. Users’ perceptions and satisfaction as indicators for sustainable beach management. Tourism and hospitality management. 2020 ;26(1):33 - 48.
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Purpose – The purpose of the paper is to analyse the importance of users’ perceptions and satisfaction as an indicator for future investment and management of beaches in a sustainable way. In the paper, the case study of Karpinjan beach (Novigrad) is presented.

Design/Methodology/Approach – For the research, a questionnaire for beach users was developed. The field research was carried out in 2017 among beach users (tourists, visitors and residents) before the investment and again in 2018 after the investment and implementation of the Green Beach Model, within the framework of the MITOMED+ project. In 2017, 23 different elements/aspects were evaluated, and in 2018 several additional elements were added for evaluation regarding content and conditions of the beach. 245 surveys were collected on Karpinjan beach in 2017, and in 2018 additional 302. In total, 547 beach users were interviewed on Karpinjan beach.

Findings – The beach users were most satisfied with the beach comfort, beautiful scenery and beach cleanliness in both years. The usefulness of specific elements, as future indicators for sustainable beach management, is discussed in the paper.

Originality of the research – The developed survey and findings can help future beach managers and local destinations as a tool for sustainable destination management.

Reservoir Fish Habitats: A Toolkit for Coping with Climate Change

Miranda LE, Coppola G, Boxrucker J. Reservoir Fish Habitats: A Toolkit for Coping with Climate Change. Norman: Reservoir Fisheries Habitat Partnership; 2020. Available from: https://www.friendsofreservoirs.com/project-update/reservoir-fish-habitats-a-toolkit-for-coping-with-climate-change/
Freely available?: 
Yes
Summary available?: 
No
Type: Report

Climate change is the defining environmental problem for our generation. The effects of climate change are increasingly evident and anticipated to profoundly affect our ability to conserve fish habitats and fish assemblages as we know them. Preparing to cope with the effects of climate change is developing as the central concern of aquatic resources conservation and management. Reservoirs are important structures for coping with projected shifts in water supply, but they also provide refuge for riverine fishes and retain distinct fish assemblages that support diverse fisheries. The effects of climate change on reservoirs are unique among aquatic systems because reservoirs have distinctive habitat characteristics due to their terrestrial origin and strong linkage to catchments. We review (1) the projected effects of rising temperature and shifting precipitation on reservoir fish habitats, and (2) adaptation strategies to cope with the anticipated effects. Climate warming impacts to reservoirs include higher water temperatures and shifts in hydrology that can result in reduced water levels in summer and fall, altered water residence cycles, disconnection from upstream riverine habitats and backwaters, increased stratification, eutrophication, anoxia, and a general shift in biotic assemblages including plants, invertebrates, and fishes. We suggest that what is needed to cope with these changes is a new perspective focusing on maintaining ecosystem functionality rather than on retaining a particular species composition. To that end, we offer a toolkit organized into planning, monitoring, and managing compartments, and equipped with 22 adaptation tools. The coping strategies we identify are broad and general and represent a starting line applicable for developing creative alternatives relevant to local conditions.

Regulating Offshore Energy: Europe as a Model for Regulation

Wright A. Regulating Offshore Energy: Europe as a Model for Regulation. North Carolina Journal of International Law [Internet]. 2019 :69-110. Available from: https://scholarship.law.unc.edu/ncilj/vol45/iss4/4
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Although the regime for managing oceans and offshore energy development are complex internationally and within the United States, some regulatory structures have proven to be both successful and adaptable in a changing energy landscape. The European Union provides a useful model for regional collaboration and marine planning, a model that could be adapted to the United States to ensure sustainable marine management as more offshore lands are opened to energy development. Many of the structures that would encourage this development have already begun to form within the United States, enabling the exact kinds of management embraced by the European model.

The Plastic Crisis Goes Public: Representations of Plastic Pollution in Environmental Media

Geary S. The Plastic Crisis Goes Public: Representations of Plastic Pollution in Environmental Media. Miami: University of Miami; 2019. Available from: https://scholarlyrepository.miami.edu/oa_theses/793
Freely available?: 
Yes
Summary available?: 
No
Type: Thesis

Plastic pollution emerged as a landmark environmental issue in the last few years, and as such, has appeared in environmental media. This thesis examines the representations of plastic pollution in environmental communication campaigns, social media of Non-Governmental Organizations (NGOs), environmental campaigns created by the advertising industry, corporate environmentalism efforts, and media from concerned individuals. While plastic materials began as a way to mimic materials found in nature, their ubiquity, heavy promotion from petrochemical companies, and widespread adoption as single-use disposables outpaced waste disposal measures. NGOs and nonprofits unite under networked environmental campaigns, invoke agenda-setting theory, and favor framing that features ocean life and marine debris. Single-use plastic straws, spurred by a viral video of a sea turtle and work from organizations like Lonely Whale, have become emblematic of plastic pollution as a whole. Plastic pollution campaigns from NGOs and advertisers and often lack clarity and calls-to-action. Among the corporations embracing anti-plastic efforts, Starbucks, Adidas, and 4ocean have differing levels of greenwashing and may or may not create a social energy penalty. Irony and self-reflexivity, as well as plastic pollution's connection to climate change, may provide avenues for environmental communication. System-based anti-plastic communication and efforts may have more of an impact than those that promote individual lifestyle changes and focus on a single item.

Changes in ocean health in British Columbia from 2001 to 2016

O’Hara CC, Scarborough C, Hunter KL, Afflerbach JC, Bodtker K, Frazier M, Lowndes JSStewart, R. Perry I, Halpern BS. Changes in ocean health in British Columbia from 2001 to 2016. PLOS ONE [Internet]. 2020 ;15(1):e0227502. Available from: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0227502
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Effective management of marine systems requires quantitative tools that can assess the state of the marine social-ecological system and are responsive to management actions and pressures. We applied the Ocean Health Index (OHI) framework to retrospectively assess ocean health in British Columbia annually from 2001 to 2016 for eight goals that represent the values of British Columbia’s coastal communities. We found overall ocean health improved over the study period, from 75 (out of 100) in 2001 to 83 in 2016, with scores for inhabited regions ranging from 68 (North Coast, 2002) to 87 (West Vancouver Island, 2011). Highest-scoring goals were Tourism & Recreation (average 94 over the period) and Habitat Services (100); lowest-scoring goals were Sense of Place (61) and Food Provision (64). Significant increases in scores over the time period occurred for Food Provision (+1.7 per year), Sense of Place (+1.4 per year), and Coastal Livelihoods (+0.6 per year), while Habitat Services (-0.01 per year) and Biodiversity (-0.09 per year) showed modest but statistically significant declines. From the results of our time-series analysis, we used the OHI framework to evaluate impacts of a range of management actions. Despite challenges in data availability, we found evidence for the ability of management to reduce pressures on several goals, suggesting the potential of OHI as a tool for assessing the effectiveness of marine resource management to improve ocean health. Our OHI assessment provides an important comprehensive evaluation of ocean health in British Columbia, and our open and transparent process highlights opportunities for improving accessibility of social and ecological data to inform future assessment and management of ocean health.

Protection reveals density-dependent dynamics in fish populations: A case study in the central Mediterranean

Melià P, Casagrandi R, Di Franco A, Guidetti P, Gatto M. Protection reveals density-dependent dynamics in fish populations: A case study in the central Mediterranean. PLOS ONE [Internet]. 2020 ;15(2):e0228604. Available from: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0228604
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Casting light on how the interaction between protection and density dependence affects fish population dynamics is critical for understanding the effectiveness of marine protected areas (MPAs). We developed a framework based on nonparametric statistics, model selection and multi-model inference to contrast alternative hypotheses about the effect of density dependence on demographic dynamics under protected and unprotected conditions. We trialed it using a 12-year long time series of white seabream (Diplodus sargus sargus) population density within the no-take zone of Torre Guaceto MPA (Italy) and at two nearby unprotected locations. Then, we showed how the demographic models obtained can be used to assess the consequences of protection on population viability. Population dynamics were significantly influenced by fish density within the MPA and at one of the unprotected locations, where demography is possibly driven by directional recruitment subsidy from the MPA. The comparison of population growth rates within and outside the MPA suggests that in unprotected conditions the fishery may remove a fraction between 40 and 70% of the population each year. The population viability analysis pointed out that, while the probability that the population becomes depleted (i.e. undergoes a local, temporary quasi-extinction) is high in unprotected locations, it is negligible within the no-take zone of the MPA.

Coral restoration – A systematic review of current methods, successes, failures and future directions

Boström-Einarsson L, Babcock RC, Bayraktarov E, Ceccarelli D, Cook N, Ferse SCA, Hancock B, Harrison P, Hein M, Shaver E, et al. Coral restoration – A systematic review of current methods, successes, failures and future directions. PLOS ONE [Internet]. 2020 ;15(1):e0226631. Available from: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0226631
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Coral reef ecosystems have suffered an unprecedented loss of habitat-forming hard corals in recent decades. While marine conservation has historically focused on passive habitat protection, demand for and interest in active restoration has been growing in recent decades. However, a disconnect between coral restoration practitioners, coral reef managers and scientists has resulted in a disjointed field where it is difficult to gain an overview of existing knowledge. To address this, we aimed to synthesise the available knowledge in a comprehensive global review of coral restoration methods, incorporating data from the peer-reviewed scientific literature, complemented with grey literature and through a survey of coral restoration practitioners. We found that coral restoration case studies are dominated by short-term projects, with 60% of all projects reporting less than 18 months of monitoring of the restored sites. Similarly, most projects are relatively small in spatial scale, with a median size of restored area of 100 m2. A diverse range of species are represented in the dataset, with 229 different species from 72 coral genera. Overall, coral restoration projects focused primarily on fast-growing branching corals (59% of studies), and report survival between 60 and 70%. To date, the relatively young field of coral restoration has been plagued by similar ‘growing pains’ as ecological restoration in other ecosystems. These include 1) a lack of clear and achievable objectives, 2) a lack of appropriate and standardised monitoring and reporting and, 3) poorly designed projects in relation to stated objectives. Mitigating these will be crucial to successfully scale up projects, and to retain public trust in restoration as a tool for resilience based management. Finally, while it is clear that practitioners have developed effective methods to successfully grow corals at small scales, it is critical not to view restoration as a replacement for meaningful action on climate change.

Towards a global understanding of the drivers of marine and terrestrial biodiversity

Gagne TO, Reygondeau G, Jenkins CN, Sexton JO, Bograd SJ, Hazen EL, Van Houtan KS. Towards a global understanding of the drivers of marine and terrestrial biodiversity. PLOS ONE [Internet]. 2020 ;15(2):e0228065. Available from: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0228065
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Understanding the distribution of life’s variety has driven naturalists and scientists for centuries, yet this has been constrained both by the available data and the models needed for their analysis. Here we compiled data for over 67,000 marine and terrestrial species and used artificial neural networks to model species richness with the state and variability of climate, productivity, and multiple other environmental variables. We find terrestrial diversity is better predicted by the available environmental drivers than is marine diversity, and that marine diversity can be predicted with a smaller set of variables. Ecological mechanisms such as geographic isolation and structural complexity appear to explain model residuals and also identify regions and processes that deserve further attention at the global scale. Improving estimates of the relationships between the patterns of global biodiversity, and the environmental mechanisms that support them, should help in efforts to mitigate the impacts of climate change and provide guidance for adapting to life in the Anthropocene.

Abundance, size, and survival of recruits of the reef coral Pocillopora acuta under ocean warming and acidification

Bahr KD, Tran T, Jury CP, Toonen RJ. Abundance, size, and survival of recruits of the reef coral Pocillopora acuta under ocean warming and acidification. PLOS ONE [Internet]. 2020 ;15(2):e0228168. Available from: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0228168
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Ocean warming and acidification are among the greatest threats to coral reefs. Massive coral bleaching events are becoming increasingly common and are predicted to be more severe and frequent in the near future, putting corals reefs in danger of ecological collapse. This study quantified the abundance, size, and survival of the coral Pocillopora acuta under future projections of ocean warming and acidification. Flow-through mesocosms were exposed to current and future projections of ocean warming and acidification in a factorial design for 22 months. Neither ocean warming or acidification, nor their combination, influenced the size or abundance of P. acuta recruits, but heating impacted subsequent health and survival of the recruits. During annual maximum temperatures, coral recruits in heated tanks experienced higher levels of bleaching and subsequent mortality. Results of this study indicate that P. acutais able to recruit under projected levels of ocean warming and acidification but are susceptible to bleaching and mortality during the warmest months.

Estimating Global Catches of Marine Recreational Fisheries

Freire KMeirelles, Belhabib D, Espedido JC, Hood L, Kleisner KM, Lam VWL, Machado ML, Mendonça JTomasino, Meeuwig JJ, Moro PS, et al. Estimating Global Catches of Marine Recreational Fisheries. Frontiers in Marine Science [Internet]. 2020 ;7. Available from: https://www.frontiersin.org/article/10.3389/fmars.2020.00012/full
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Commercial fisheries catches by country are documented since 1950 by the Food and Agriculture Organization (FAO). Unfortunately, this does not hold for marine recreational catches, of which only few, if any, estimates are reported to FAO. We reconstructed preliminary estimates of likely marine recreational catches for 1950–2014, based on independent reconstructions for 125 countries. Our estimates of marine recreational catches that are retained and landed increased globally until the early 1980s, stabilized through the 1990s, and began increasing again thereafter, amounting to around 900,000 t⋅year–1 in 2014. Marine recreational catches thus account for slightly less than 1% of total global marine catches. Trends vary regionally, increasing in Asia, South America and Africa, while slightly decreasing in Europe and Oceania, and strongly decreasing in North America. The derived taxonomic composition indicates that recent catches were dominated by Sparidae (12% of total catches), followed by Scombridae (10%), Carangidae (6%), Gadidae (5%), and Sciaenidae (4%). The importance of Elasmobranchii (sharks and rays) in recreational fisheries in some regions is of concern, given the life-history traits of these taxa. Our preliminary catch reconstruction, despite high data uncertainty, should encourage efforts to improve national data reporting of recreational catches.

Impact on Macro-Benthic Communities of Hydraulic Dredging for Razor Clam Ensis minor in the Tyrrhenian Sea

Vasapollo C, Virgili M, Bargione G, Petetta A, De Marco R, Punzo E, Lucchetti A. Impact on Macro-Benthic Communities of Hydraulic Dredging for Razor Clam Ensis minor in the Tyrrhenian Sea. Frontiers in Marine Science [Internet]. 2020 ;7. Available from: https://www.frontiersin.org/article/10.3389/fmars.2020.00014/fullhttps://www.frontiersin.org/article/10.3389/fmars.2020.00014/fullhttps://www.frontiersin.org/articles/10.3389/fmars.2020.00014/supplementary-material/10.3389/fmars.2020.00014.s001
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Bivalve molluscs fishery is of great importance along the Italian coasts, both in economic and landing terms, and different edible bivalve species are harvested both in Adriatic and Tyrrhenian Seas. A medium-term assessment of the impact of the hydraulic dredges targeting razor clam Ensis minor on macro-benthic community was made during two surveys carried out in winter 2017 and late spring – summer 2018 in central Tyrrhenian Sea, which represents the main fishing ground for this species. The study area was located between 1 and 4 m depth, within 0.3 nautical miles from the coast. A net sampler (40 cm width, 18 cm height, and 14 mm mesh size) was mounted on a commercial dredge (3 m width) and enabled to collect specimens of the smallest sizes for the entire community present in the areas. A control area was identified where fishing does not occur, in order to compare exploited and not exploited sea bottoms. The results show that benthic assemblages found in dredged areas are characterized by species living in high-energy habitat, due to the closeness to the shore, and thus showing a high resilience at medium-term disturbs. Differences in species richness were not clearly evident both for the entire community and for the mollusc assemblages evaluated over the two surveys, among the control and the impacted areas, with few exceptions mainly depending on local conditions and anthropic pressure. Thus, even if the benthic community is typical of a moderately disturbed environment, the effects of fishing on the community structure are still discernible over and above the natural variation.

Long-Term Fishing Catch and Effort Trends in the Republic of the Marshall Islands, With Emphasis on the Small-Scale Sectors

Vianna GMS, E. Hehre J, White R, Hood L, Derrick B, Zeller D. Long-Term Fishing Catch and Effort Trends in the Republic of the Marshall Islands, With Emphasis on the Small-Scale Sectors. Frontiers in Marine Science [Internet]. 2020 ;6. Available from: https://www.frontiersin.org/article/10.3389/fmars.2019.00828/full
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Small-scale fishing has been an important element of the livelihood and food security in Pacific island countries throughout history; however, such catches have been under-reported in the official fisheries data. Here, we reconstruct the total domestic catches and fishing effort of the Republic of the Marshall Islands (RMI) by fishing sectors for 1950–2017. Reconstructed total catches were estimated to be 27% higher than the data officially reported by the Food and Agriculture Organization (FAO) of the United Nations on behalf of the RMI. Catches of the truly domestic, but export-oriented, industrial tuna sector accounted for 84% of the total catch, dominating catches since the early 2000s. The subsistence component contributed 74% of total small-scale catches, of which 92% was deemed unreported. The remaining 26% of small-scale catches were artisanal, i.e., small-scale commercial, in nature, of which 45% was deemed unreported. Trends suggested steady growth in small-scale catches from 1,100 t⋅year–1in the early 1950s to a relatively stable level of 4,500 t⋅year–1 since the 1990s. However, over the 2009–2017 period, there was a gradual reduction of 2% per year in subsistence fishing, which was paralleled by a concomitant increase in artisanal catches of 3% per year. This gradual shift from predominantly non-commercial to commercial small-scale fisheries may be related to efforts to commercialize small-scale fisheries in the past decades. Small-scale fishing effort increased approximately 13-fold from the early 1980s to the late 2000s, stabilizing at around 401,000 kWdays since then, while catch-per-unit-of-effort (CPUE) displayed an inverse pattern, declining eightfold between the 1980s and 1990s, and stabilizing around 15 kg⋅kWdays–1 in recent decades. These findings may assist sustainable coastal fisheries management in the RMI, which is particularly important given the increasing impacts of climate change on local stocks.

Rapid Assessments of Leatherback Small-Scale Fishery Bycatch in Internesting Areas in the Eastern Pacific Ocean

Ortiz-Alvarez C, Pajuelo M, Grados D, Abrego ME, Barragán-Rocha ARebeca, Barrantes M, Sánchez ACotto, Fonseca LG, Espinal VGadea, Mangel JC, et al. Rapid Assessments of Leatherback Small-Scale Fishery Bycatch in Internesting Areas in the Eastern Pacific Ocean. Frontiers in Marine Science [Internet]. 2020 ;6. Available from: https://www.frontiersin.org/article/10.3389/fmars.2019.00813/full
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

The East Pacific (EP) leatherback population is listed by the IUCN Red List of Threatened Species as Critically Endangered. Despite conservation efforts, mainly focused on nesting beaches, its population has declined by over 90% since the 1980s. A major current threat is fisheries bycatch, which has been primarily documented in small-scale gillnets and longlines within South American migration and foraging habitats, but scarcely reported in fisheries that operate in areas near nesting beaches (i.e., inter-nesting areas). To assess the impact of small-scale fisheries on EP leatherbacks inhabiting waters north of the equator we conducted rapid bycatch assessments interviews in five countries (Mexico, Nicaragua, Costa Rica, Panama and Colombia), some of which host the main EP leatherback nesting beaches and inter-nesting areas. A total of 1778 interviews were conducted across 79 fishing ports (Mexico = 37, Nicaragua = 6, Costa Rica = 5, Panama = 17 and Colombia = 14). Leatherback bycatch was reported in all countries, and in 54% of ports assessed by 7% (n = 125) of fishers interviewed. Interviews enabled identification of inter-nesting areas where leatherback bycatch was higher and periods during which fisheries interaction events were more frequent. Bycatch events were most frequently reported in gillnets and secondarily in longlines. Data were extrapolated across fishing fleets to estimate that 345 ± 210 (mean ± SD) individual leatherbacks are caught annually in the ports assessed. Our study provides a first evaluation of leatherback bycatch by small-scale fisheries in countries of the eastern Pacific Ocean where leatherbacks nest, and it highlights areas close to index nesting beaches where conservation efforts targeting bycatch reduction and bycatch mortality may be focused.

Big Fishery, Big Data, and Little Crabs: Using Genomic Methods to Examine the Seasonal Recruitment Patterns of Early Life Stage Dungeness Crab (Cancer magister) in the California Current Ecosystem

Lee EMJ, O’Malley KG. Big Fishery, Big Data, and Little Crabs: Using Genomic Methods to Examine the Seasonal Recruitment Patterns of Early Life Stage Dungeness Crab (Cancer magister) in the California Current Ecosystem. Frontiers in Marine Science [Internet]. 2020 ;6. Available from: https://www.frontiersin.org/article/10.3389/fmars.2019.00836/full
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

The California Current Ecosystem (CCE) is a dynamic marine ecosystem from which many socioeconomically important fisheries species are harvested. Here, a genotyping-by-sequencing (GBS) approach was used to examine genomic variation in an early life stage (megalopae) of the Dungeness crab (Cancer magister), which constitutes the most valuable single-species commercial fishery in the CCE. Variation in abundance and timing of megalopae recruitment has been extensively studied for over two decades in Coos Bay, Oregon, United States. Within the CCE, documented timing of Dungeness crab life history events indicates that coastal megalopae recruitment is expected to occur April through July; however, long-term studies in Coos Bay have observed late-season recruitment from August to October. Based on variation at 1,913 presumably neutral loci, evidence was found for weak, yet significant differentiation (FST estimate = 0.0011) between the 2014 expected-season recruits (n = 47) and late-season recruits (n = 47) collected in Coos Bay. However, two putatively adaptive loci with a high FSTestimate (0.2036) between expected-season and late-season recruits were identified. These findings support the hypothesis that expected-season and late-season megalopae recruiting to Coos Bay within the same year may have originated from different locations or from different breeding groups. Understanding marine species connectivity between ecosystems is important when considering how future changes in ocean conditions may impact fishery harvests.

Contrasting Changes in Diel Variations of Net Community Calcification Support That Carbonate Dissolution Can Be More Sensitive to Ocean Acidification Than Coral Calcification

Chou W-C, Liu P-J, Chen Y-H, Huang W-J. Contrasting Changes in Diel Variations of Net Community Calcification Support That Carbonate Dissolution Can Be More Sensitive to Ocean Acidification Than Coral Calcification. Frontiers in Marine Science [Internet]. 2020 ;7. Available from: https://www.frontiersin.org/article/10.3389/fmars.2020.00003/full
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Previous studies have found that calcification in coral reefs is generally stronger during the day, whereas dissolution is prevalent at night. On the basis of these contrasting patterns, the diel variations of net community calcification (NCC) were monitored to examine the relative sensitivity of CaCO3 production (calcification) and dissolution in coral reefs to ocean acidification (OA), using two mesocosms that replicated a typical subtropical coral reef ecosystem in southern Taiwan. The results revealed that the daytime NCC remained unchanged, whereas the nighttime NCC decreased between the control (ambient) and treatment (OA) conditions, suggesting that carbonate dissolution could be more sensitive to OA than coral calcification. The average sensitivity of the integrated daily NCC to changes in the seawater saturation state (Ωa) was estimated to be a reduction of 54% in NCC per unit change in Ωa, which is consistent with the global average. In summary, our results support the prevailing anticipation that OA would lead to a reduction in the overall accretion of coral reef ecosystems. However, increased CaCO3 dissolution rather than decreased coral calcification could be the dominant driving force responsible for this OA-induced reduction in NCC.

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