Coral disease is one of the major causes of reef degradation. Dark Spot Syndrome (DSS) was described in the early 1990's as brown or purple amorphous areas of tissue on a coral and has since become one of the most prevalent diseases reported on Caribbean reefs. It has been identified in a number of coral species, but there is debate as to whether it is in fact the same disease in different corals. Further, it is questioned whether these macroscopic signs are in fact diagnostic of an infectious disease at all. The most commonly affected species in the Caribbean is the massive starlet coral Siderastrea siderea. We sampled this species in two locations, Dry Tortugas National Park and Virgin Islands National Park. Tissue biopsies were collected from both healthy colonies and those with dark spot lesions. Microbial-community DNA was extracted from coral samples (mucus, tissue, and skeleton), amplified using bacterial-specific primers, and applied to PhyloChip G3 microarrays to examine the bacterial diversity associated with this coral. Samples were also screened for the presence of a fungal ribotype that has recently been implicated as a causative agent of DSS in another coral species, but the amplifications were unsuccessful. S. siderea samples did not cluster consistently based on health state (i.e., normal versus dark spot). Various bacteria, including Cyanobacteria and Vibrios, were observed to have increased relative abundance in the discolored tissue, but the patterns were not consistent across all DSS samples. Overall, our findings do not support the hypothesis that DSS in S. siderea is linked to a bacterial pathogen or pathogens. This dataset provides the most comprehensive overview to date of the bacterial community associated with the scleractinian coral S. siderea.
The United Nations General Assembly Resolution 61/105, concerning sustainable fisheries in the marine ecosystem, calls for the protection of vulnerable marine ecosystems (VME) from destructive fishing practices. Subsequently, the Food and Agriculture Organization (FAO) produced guidelines for identification of VME indicator species/taxa to assist in the implementation of the resolution, but recommended the development of case-specific operational definitions for their application. We applied kernel density estimation (KDE) to research vessel trawl survey data from inside the fishing footprint of the Northwest Atlantic Fisheries Organization (NAFO) Regulatory Area in the high seas of the northwest Atlantic to create biomass density surfaces for four VME indicator taxa: large-sized sponges, sea pens, small and large gorgonian corals. These VME indicator taxa were identified previously by NAFO using the fragility, life history characteristics and structural complexity criteria presented by FAO, along with an evaluation of their recovery trajectories. KDE, a non-parametric neighbour-based smoothing function, has been used previously in ecology to identify hotspots, that is, areas of relatively high biomass/abundance. We present a novel approach of examining relative changes in area under polygons created from encircling successive biomass categories on the KDE surface to identify “significant concentrations” of biomass, which we equate to VMEs. This allows identification of the VMEs from the broader distribution of the species in the study area. We provide independent assessments of the VMEs so identified using underwater images, benthic sampling with other gear types (dredges, cores), and/or published species distribution models of probability of occurrence, as available. For each VME indicator taxon we provide a brief review of their ecological function which will be important in future assessments of significant adverse impact on these habitats here and elsewhere.
While increasing atmospheric carbon dioxide (CO2) concentration alters global water chemistry (Ocean Acidification; OA), the degree of changes vary on local and regional spatial scales. Inshore fringing coral reefs of the Great Barrier Reef (GBR) are subjected to a variety of local pressures, and some sites may already be marginal habitats for corals. The spatial and temporal variation in directly measured parameters: Total Alkalinity (TA) and dissolved inorganic carbon (DIC) concentration, and derived parameters: partial pressure of CO2 (pCO2); pH and aragonite saturation state (Ωar) were measured at 14 inshore reefs over a two year period in the GBR region. Total Alkalinity varied between 2069 and 2364 µmol kg−1 and DIC concentrations ranged from 1846 to 2099 µmol kg−1. This resulted in pCO2 concentrations from 340 to 554 µatm, with higher values during the wet seasons and pCO2 on inshore reefs distinctly above atmospheric values. However, due to temperature effects, Ωar was not further reduced in the wet season. Aragonite saturation on inshore reefs was consistently lower and pCO2 higher than on GBR reefs further offshore. Thermodynamic effects contribute to this, and anthropogenic runoff may also contribute by altering productivity (P), respiration (R) and P/R ratios. Compared to surveys 18 and 30 years ago, pCO2 on GBR mid- and outer-shelf reefs has risen at the same rate as atmospheric values (~1.7 µatm yr−1) over 30 years. By contrast, values on inshore reefs have increased at 2.5 to 3 times higher rates. Thus, pCO2 levels on inshore reefs have disproportionately increased compared to atmospheric levels. Our study suggests that inshore GBR reefs are more vulnerable to OA and have less buffering capacity compared to offshore reefs. This may be caused by anthropogenically induced trophic changes in the water column and benthos of inshore reefs subjected to land runoff.
Bull sharks (Carcharhinus leucas) are globally distributed top predators that play an important ecological role within coastal marine communities. However, little is known about the spatial and temporal scales of their habitat use and associated ecological role. In this study, we employed passive acoustic telemetry to investigate the residency patterns and migration dynamics of 18 adult bull sharks (195–283 cm total length) tagged in southern Mozambique for a period of between 10 and 22 months. The majority of sharks (n = 16) exhibited temporally and spatially variable residency patterns interspersed with migration events. Ten individuals undertook coastal migrations that ranged between 433 and 709 km (mean = 533 km) with eight of these sharks returning to the study site. During migration, individuals exhibited rates of movement between 2 and 59 km.d−1 (mean = 17.58 km.d−1) and were recorded travelling annual distances of between 450 and 3760 km (mean = 1163 km). Migration towards lower latitudes primarily took place in austral spring and winter and there was a significant negative correlation between residency and mean monthly sea temperature at the study site. This suggested that seasonal change is the primary driver behind migration events but further investigation is required to assess how foraging and reproductive activity may influence residency patterns and migration. Results from this study highlight the need for further understanding of bull shark migration dynamics and suggest that effective conservation strategies for this vulnerable species necessitate the incorporation of congruent trans-boundary policies over large spatial scales.
Trophy fishing occurs when anglers target the largest members of a species with the goal of obtaining an award with perceived prestige. The largest members of many species are also the most fecund, raising alarms about the disproportionate impact of removing the largest individuals of species of conservation concern. Presented here is the first systematic analysis of the conservation status of fishes targeted for world records by the International Game Fishing Association. Eighty-five species for which IGFA records have been issued are listed as Threatened by the International Union for the Conservation of Nature (IUCN) Red List. If the IGFA stopped issuing records that implicitly require killing the fish for IUCN Red List Threatened species, it would immediately reduce fishing pressure on the largest individuals of species of conservation concern while still allowing anglers to target more than 93% of species that records have been issued for.
In recreational fisheries with large angler populations, monitoring catch overages is a challenge faced by fisheries managers. A possible solution to this issue is sector separation, which would split the recreational fishery into two angler groups: for-hire (made up of charter boats and headboats) and private. This division would allow the two sectors to have individual Annual Catch Limits (ACLs) and tailored management. This paper uses the Gulf of Mexico recreational red snapper fishery as a case study to examine the impacts of sector separation. Because for-hire anglers can already be regulated and catch limits for private anglers remain hard to enforce, sector separation will have minimal effects on the biology of the red snapper fishery. Economic changes under sector separation are driven by management decisions regarding allocation and by the reality of overage liability. Depending on the ACL allocations and which sector is landing the overages, the for-hire sector can see economic gains with the implementation of sector separation.
In recent years, cooperative management systems have received attention as a means towards sustainable fisheries. Since its inception and for the past 20 years, the gooseneck barnacle fishery in the coast of Asturias has been co-managed by assigning Territorial User Rights to fishers׳ associations, allowing fishers to participate actively in the management and data gathering processes. Here, 20 years of landings, in-depth interviews and focus groups were used to characterize the emergence and social-ecological properties of the system. The system consists of 7 management areas each one some tens of kilometers long. The incorporation of fishers׳ knowledge has successfully led to within-area fragmentation of the management units down to single rocks as small as 3 m long, which are managed according to different protection levels. The system has empowered resource users and provided an opportunity for the use of both scientific information and fishers׳ knowledge to be integrated in management guidelines. Results suggest the adaptive capacity provided by the co-management framework has been essential to manage this heterogeneous fishery. The gooseneck barnacle fishery and its historical developments illustrate the potential for establishing co-management systems for small-scale fisheries in Europe.
Multi-scale governance has been widely recommended for effective marine resource management. This approach suggests collective decision-making, the devolution of some rights and responsibilities to various entities, co-production of knowledge, coupling governance and ecological scales, among other elements. Here, the elements of multi-scale governance of Mexican small-scale fisheries (SSF) and the contribution of non-governmental organizations (NGOs) to this approach are described. Three management processes were selected for the analysis: (1) the development of the Fisheries Management Plan (FMP) for the swimming crab fishery; (2) the establishment of fishing refugia in the Punta San Cosme to Punta Coyote Corridor; and (3) the implementation of catch shares in the Gulf corvina fishery. The results suggest that NGOs are contributing to most of the key attributes for multi-scale fisheries governance. Given the NGOs׳ agenda shift in the Gulf of California region, from advocacy for environmental conservation to participation in sustainable management, there has been a wider promotion and acceptance of NGOs within governance related processes in fisheries management. In order to clarify alignments with other stakeholder agendas, as well as to continue building trust, NGOs need to make their governance agenda explicit. This work provides insights on how NGOs can contribute to multi-scale governance and a framework for the evaluation of management processes and the contribution of different stakeholders to multi-scale governance, which can be applied to any management process.
Many fisheries worldwide have exhibited marked decreases in profitability and fish stocks during the last few decades as a result of overfishing. However, more conservative, science- and incentive-based management approaches have been practiced in the US federally managed fisheries off Alaska since the mid-1990s. The Bering Sea pollock fishery is one such fishery and remains one of the world׳s largest in both value and volume of landings. In 1998, with the implementation of the American Fisheries Act (AFA) this fishery was converted from a limited access fishery to a rationalized fishery in which fishing quota were allocated to cooperatives which could transfer quotas, facilitate fleet consolidation, and maximize efficiency. The changes in efficiency and productivity growth arising from the change in management regime have been the subject of several studies, with a few focusing on the large vessels that both catch and process fish onboard (catcher-processors). This study modifies existing approaches to account for the unique decision making process characterizing catcherprocessor׳s production technologies. The focus is on sequential decisions regarding what products to produce and the factors that influence productivity once those decisions are made, using a multiproduct revenue function. The estimation procedure is based on a latent variable econometric model and departs from and advances previous studies since it deals with the mixed distribution nature of the data, a novel application to fisheries production modeling. The resulting productivity growth estimates are consistent with increasing productivity growth since rationalization of the fishery, even in light of large decreases in the pollock stock. These findings suggest that rationalizing fishery incentives can help foster improvements in economic productivity even during periods of diminished biological productivity.
Community-based fisheries management (CBFM) strategies have been adopted in a variety of small-scale fisheries around the world. Within these management structures, leaders are increasingly regarded as essential for viable CBFM yet systematic analysis into the intricate mechanisms of leadership are limited. This paper aims to identify key knowledge gaps of leadership in CBFM by strategically reviewing research from fisheries and natural resource management, and from other sectors. The focus is on the interaction between leaders, their connections with and beyond their communities, and the context within which leaders function. Insights from over 30 case studies suggest previous work on leaders and leadership generally focused on relatively coarse-scale characteristics of leadership and the functions that leaders perform. Ecological and social context influence leaders׳ ability to help deliver successful CBFM. The personal and professional attributes of leaders themselves may be beneficial or inhibitory for CBFM depending on that context. It is therefore essential that future research builds on current insight in order to decipher the implications of contextual influences on local leadership and, by extension, the level of CBFM success.
This paper uses the Western Australian rock lobster, the first fishery certified by MSC, as a case study to discuss some of the environmental issues encountered in MSC׳s Principle 2 and the strategies implemented to address them. Experience with the certification of Western Australian rock lobster has highlighted the importance of; comprehensive documentation of current and historical information, monitoring and research, a transparent process of risk identification and the value of an independent advisory group to review risks and guide research directions.A comparison of other certified lobster fisheries worldwide revealed that third party certification consistently identified specific environmental issues, indicating that the strategies implemented to support the ongoing certification of the Western Australian rock lobster fishery may be relevant to other fisheries.
The Alaska head and gut (H&G) fishing fleet, a major component of the Bering Sea Aleutian Islands region (BSAI) groundfish fisheries, was recently rationalized under Amendment 80 (A80) to the BSAI groundfish fishery management plan. Economic impacts from H&G sector activities occur not only in Alaska but also extend to other U.S. regions via economic linkages with economic agents in those regions. Using a multiregional social accounting matrix (MRSAM) model of three U.S. regions (Alaska, West Coast, and rest of USA), the multiregional contribution of the H&G industry is estimated, and multiregional impacts of selected shifts in H&G sector production are evaluated in terms of changes in output, employment and income. Results indicate that the A80 H&G fleet vessels are important participants in Alaska fisheries, that more than half of the impacts from the H&G fleet on total output and about 80% of the impacts on household income accrue outside Alaska, and that the H&G fleet is relatively insensitive to variations in world prices of its primary products.
As a precautionary measure to protect the culturally-significant bowhead whale (Balaena mysticetus) from vessel strike, this paper explores the potential for having the International Maritime Organization endorse ships׳ routeing measures in the Bering Strait region. The confined nature of the Bering Strait forces both vessel traffic and the migrating Bering–Chukchi–Beaufort stock of bowhead whales to occupy the same narrow space, thus putting individual animals at risk of vessel strike. The potential for vessel strike may become exacerbated as the reduction of Arctic sea ice makes the Arctic increasingly accessible, allowing vessels to transit through the Strait in greater densities. In drawing from lessons learned in the successful reduction of vessel strike to the North Atlantic right whale (Eubalaena glacialis), the author provides broad recommendations for implementing ships׳ routeing measures in the Bering Strait region based on findings by Citta et al. (2012). It is recommended that both the western side of Big Diomede Island and the western side of St. Lawrence Island be designated as seasonal Areas To Be Avoided (ATBA) during fall months when bowheads are known to inhabit the area. Alternatively, it is proposed that Traffic Separation Schemes (TSSs) be implemented so that vessels must keep to the eastern side of both Big Diomede Island and St. Lawrence Island during this time. Both measures would reduce the amount of overlap between migrating bowhead whales and transiting vessel traffic, effectively reducing the potential for vessel strike.
MSY objectives are being adopted as major fisheries management targets worldwide. However, in fisheries where discards account for an important share of the catches, the yield, effort, and biomass at MSY can be significantly different when accounting or not for discards and thus when, basing the yield estimations on landings or catches. Also whether accounting for a certain survival rate, of discards can lead to different MSY targets estimates. Hence, both decisions have important, implications on catch and effort reduction recommendations, and consequently on the quota, calculations for fisheries managed by quotas. Results from the Bay of Biscay nephrops fishery confirm, that the optimal exploitation level can vary significantly when optimising for catches or landings, and, by assuming a certain survival rate of the discards. By doing this, the present study also allows to, explore the basis to clarify the definition of MSY in fisheries where discarding takes place.
Aquaculture is the fastest growing global food system, providing nearly half of the world׳s seafood supply. A significant portion of aquaculture is produced in the global South and consumed in the North, with much of the production stemming from small producers in Asian countries. The rapid growth in this sector has led to a host of social, environmental and governance concerns, with certification emerging as one market governance response. This paper assesses the potential of certification for small producer shrimp farmers in Vietnam, examining the ways in which three standards operating in Vietnam focus on social, environmental, economic, and management dimensions of sustainability. Research findings suggest that aquaculture standards are not appropriate for small producers since much of the current criteria are not viable at this scale. A separate national standard customized specifically for small producers in Vietnam׳s aquaculture sector may be necessary. A set of guidelines is proposed as a starting point for discussions regarding small producer certification.
This article aims to address fishery adaptation to tackle the commons dilemma by introducing the Padu system. The Padu system which is a gear-specific fishery with strict rules has survived to date, but the system has become vulnerable due to exogenous pressures as well as internal population growth. With this background, the research presents a case study of stake-seine fishery in Negombo Lagoon, Sri Lanka by highlighting the institutional mechanism of the Padu system. Findings revealed that the system has developed a nested structure of fishery governance among right holders. A role of the Roman Catholic Church served as a basis for interaction vertically across institutions from local to national, securing robust fishery institutions against entry of outsiders to the system. Furthermore, the fishery introduced a welfare scheme, contributing to the adherence to their own rules including entry rights to the system which control internal population growth. Based on these findings, this article provides several implications to sustainable fishery resources management through the Padu system.
An ecosystem services (ES) approach to managing marine and coastal resources has increasingly emerged as a core requirement of ecosystem-based management (EBM). However, little practical guidance exists to help structure and implement such an approach. This paper outlines the linkages between ecosystems, ES and EBM in a practical framework that could be applied to marine environmental management. Using the northwestern, deepwater Gulf of Mexico as a case study, a three-stage approach was devised: (1) prioritizing relevant ES according to perceived financial and societal value and level of stress, (2) assessing the effectiveness of a wide range of indicators of ES health, and (3) ranking indicators to identify those whose monitoring would be most effective in tracking ES health. The first stage of this approach identified food provision, recreational fishing, and the non-use ethical value derived from the presence of iconic species as the highest-priority ES in the case study region. The second and third stages suggested four indicators as having the highest priority for supporting key ES: (1) levels of selected chemical compounds in key species of fish, (2) marine sound, (3) concentration of chlorophyll-a as a proxy for phytoplankton, and (4) economic and ecological values added by artificial structures. Results of this study will be helpful in prioritizing the allocation of resources for marine environmental monitoring. The approach described here will also be applicable, with appropriate adaptations, to ES analysis in other environmental settings.
This paper aims to explore how the non-flag state high seas boarding and inspection (HSBI) scheme has been implemented in real settings, as well as to examine its effectiveness in enforcement and potential impacts on fisheries management. The methods of document analysis and semi-structured interviews were employed. The preliminary results showed that the scheme has been practically realized in the WCPFC, indicating that an exception to the high seas flag state control has been established for the sake of fisheries management. The results also revealed that the scheme has the potential to complement the lack of on-sight enforcement capacity of fishing states, enhance cooperative enforcement on the high seas, and implicitly elevate the level of compliance with relevant management measures by vessels. This paper also identified a potential loophole of the scheme, namely whether it has the necessary “teeth” to deal with the inaction of the flag states regarding their fishing vessels which have had foreign inspectors detect the violation of rules. To amend this loophole, devising a mechanism for allowing the WCPFC to warn or punish the flag states for such inaction in order to improve compliance, has been recommended. In addition, further studies on the effectiveness of the scheme and the link between the scheme and fishers’ behaviors in complying with management measures were also recommended.
Humans and ecosystems are inextricably linked. The marine environment provides significant benefits to humans often described as stemming from ecosystem services (ES). Cultural ecosystem services (CESs) are included in the majority of ecosystem service frameworks in some form. However, there is a lack of characterisation or valuation of CESs often because they are hard to identify. They are therefore frequently left out of assessments leading to a risk that ES frameworks are not being used to their full potential. By analysing responses from the Turkish public to an open question, posed about the sea, it is possible to access the interface between humans and the marine ecosystem. A number of CES categories were identified; aesthetic information, recreation, inspiration for art and design, and cultural heritage. In addition, provisioning (seafood), air purification and climate modification were recognised. The four CES are characterised, including the hard to identify intangible elements, and the underpinning environmental components and linkages were explored. The analysis used revealed the intangible benefits, including a deeply emotional attachment to the marine environment. The understanding of the cultural linkages between the Turkish people and the Black Sea provides a mechansim for designing policy and ecosystem management measures, and for motivating individuals and communities to work towards protecting and enhancing ecosystems. The research also provides evidence to support the case that cultural experiences are frequently built upon the foundations of a healthy natural environment.
Oyster harvest has long been an important industry of the eastern coast of the United States. However, coastal development, overfishing and climate change are threatening this industry and way of life. This study examines the perspectives of oyster harvesters and merchants in Brunswick County, North Carolina, USA to explore their capacity to adapt to these changing conditions. Using in-person, semi-structured interviews researchers collected information from seventeen interviewees, generating qualitative data that were analyzed using MAXQDA software. From the data collected several themes emerged revealing mixed sentiments on the impacts of climate change but a widespread sense that development and regulations threaten livelihoods and cultural heritage. This social–ecological system (SES), created through centuries of regulation, is experiencing rapid population growth with concurrent coastal development; it also includes oyster industry workers who have limited voice in decision-making but are affected by the political ecology of the region. Deliberately including oyster harvesters and merchants when formulating and implementing policy can help to strengthen the adaptive capacity of this SES while sustaining Brunswick County׳s coastal heritage.