Fishermen responses on marine protected areas in the Baltic cod fishery

Much of the research that concerns the impacts of management measures in the eastern Baltic cod fishery has focused on fish stock rather than understanding fishermen's attitudes towards regulations. Hence, there is little information available on fishermen's responses although they are the ones whom the regulations affect most profoundly. This study analyses the views of fishermen towards management measures with an emphasis on fishing closures (marine protected areas, MPAs). Swedish log-book data from 1996 to 2005 were used to describe MPA induced fishing effort displacements. Fishermen argued that MPAs have been inefficient in conservation of cod stock. The enlargement of Bornholm MPA in 2005 caused substantial effort displacement towards areas dominated by smaller sized fish. This contributed to the increased discarding of juvenile cod. Enlarged MPAs also intensified competition between different fleet segments and reallocated fishing areas. To reduce fishing mortality, fishermen suggested days-at-sea (effort) regulation and an effective landings control system for all fleets that exploit cod stocks in the Baltic Sea Main Basin. These measures would better motivate fishermen for mutual rule compliance, which is a prerequisite for a sustainable cod fishery.     

Modelling the effects of Marine Protected Areas (MPAs) on the southern rock lobster (Jasus edwardsii) fishery of Victoria,Australia

Since 2002, 5.3% of the Victorian coastal waters have been declared as Marine Protected Areas (MPAs). These are aimed at safeguarding important marine habitats and species, significant natural features, and areas of cultural heritage and aesthetic value. However, MPAs impact the fishery for southern rock lobster (Jasus edwardsii), as total allowable catches (TACs) were previously set to allow the biomass to recover to pre‐specified target levels. The model on which assessments and risk analyses are based is extended to include the impact of MPAs. The MPAs and the area open to fishing are modelled as subpopulations with different levels of mortality and consequently different density and population size‐structure. A range for the probability of a lobster moving from a MPA to the fished area from 0 to 15% is considered, based on the results of tagging studies. The reduction of biomass available to the commercial fishery because of the introduction of MPAs is estimated to be 8% and 16% (Western and Eastern Zones) respectively. The results of a risk assessment show that if the current TACs are maintained, the time to increase the biomass available to the commercial fishery by 50% would be delayed 5–9 years in the Western Zone and 1–4 years in the Eastern Zone because of the impact of displaced effort. In contrast, spawning biomass in the Eastern Zone is currently below the agreed limit reference point, and the introduction of MPAs would enhance the rate of recovery, although only marginally initially, faster than the absence of the MPAs.     

Evaluating impacts of pulse fishing on the effectiveness of seasonal closure

Seasonal fishing closures are often used in fisheries management to conserve overfished stocks.As one of the unintended consequences,fishermen often contend for maximizing catches immediately after reopening fisheries.The resultant large catch landings in a short time period(i.e.,pulse fishing)may undermine the benefit of closure.We implemented an end-to-end model OSMOSE-JZB(Object-oriented Simulator of Marine ec OSystem Exploitation OSMOSE)modelling ecosystem in the Jiaozhou Bay located in China to evaluate the impact of pulse fishing on the effectiveness of seasonal closure at levels of fish community,population,and individual.Our study demonstrated that the three-month closure was successful in conserving fish stocks.There were small variations on ecological indicators(i.e.,total biomass of the community,mean trophic level of the community,mean trophic level of the catch,and Shannon-Wiener biodiversity index)when pulse fishing occurred.Pulse fishing seemed not to result in a great shift in community structure.Compared to other species,the biomass of two large predatory fishes were more susceptible to pulse fishing.Pulse fishing could change the pressure of predators to fish stocks via food webs,especially for young individuals.Our simulations indicate that we can improve the effectiveness of seasonal closure by managing pulse fishing.Although the results derived in this study may be specific to the target ecosystem,the general approach is applicable to other ecosystems when evaluating fishing impacts.     

Commercial fisheries closures in marine protected areas on Canada’s Pacific coast: The exception,not the rule

No-take marine protected areas (MPAs), where all fishing is prohibited, have been shown to provide benefits that include greater productivity of fish stocks due to increased densities, average sizes, and reproductive output. A critical component of this success is the effective management of MPAs to ensure that only those activities deemed permissible, are allowed to occur. As of 2008, 161 MPAs had been designated on the Pacific coast of Canada by federal, provincial or municipal authorities. The objective of this study was to discover how many of these MPAs are intended to provide full protection to habitats and species from commercial fishing and whether management measures were put in place to actualize this conservation intent. The comprehensive spatial dataset was built illustrating commercial fisheries closures and this was overlaid with MPA locations in a GIS. The majority of MPAs were designated as IUCN Strict Nature Reserve (Type Ia), Wilderness Area (Type Ib), and National Park (Type II) marine reserves, which are intended to be free from exploitation. It was found that 160 of the 161 MPAs are open to some commercial harvesting within their bounds. One small municipal MPA and portions of three other MPAs are not open to commercial harvesting. The incongruence between management intent and fisheries permitted suggests a management failure between designation of MPAs and implementation of fisheries management regulations.     

Evaluation of the “fishing down marine food web” process in the north-west of Persian Gulf(Khuzestan Province) during the period of 2002–2011

The worldwide increase in commercial fisheries and its impact on ecosystems as well as inefficient fishery management have led to overfishing and frequent breakdown of traditional fish stocks.In this context,an analysis of Khuzestan inshore fisheries data covering the years 2002–2011,was conducted in reliance on testing for occurrence of the fishing down marine food webs(FDMFW) phenomenon in the North of Persian Gulf Large Marine Ecosystem(LME).In this study,the mean trophic level(m TL) and the fishing-in-balance(FIB)-index of Khuzestan landings during this period of time were estimated using the trophic level of 47 fishery resources.Increase in total landings(Y) was observed,which explained the high fishing yield in major fishery resources(especially demersal).Moreover,the moderates decreasing trend in m TL per decade,and the increasing trend in FIB-index were observed.The status of fishery resources in Khuzestan inshore waters(under exploited but not overexploited),the rise in Y,FIB and slightly drop in m TL can be considered as indirect indicators of the fishing impacts on the trophic structure of marine communities.Based on this result,probability occurrence of FDMFW process in Khuzestan inshore waters is low to some extent.However,we suggest that the goal of management programs in Khuzestan inshore waters should prevent the continuance of this trend in the long-term using an ecosystem-based approach.     

The California Marine Life Protection Act: A balance of top down and bottom up governance in MPA planning

California recently established a state-wide MPA network that extends over 1900 km of coastline and includes 124 MPAs totaling nearly 2200 km². Designing and implementing such an MPA network in a populous democratic state with a large number of ocean users required a balance of top-down and bottom-up governance strategies. A legal mandate for MPAs identified the goals for the network and stipulated that scientific knowledge should form the basis of MPA design, while political necessity led to a participatory stakeholder-driven MPA design process. At the time of publication, the oldest region of the network was just five years old, so it remains to be seen how the governance strategies employed in MPA planning will evolve to meet the challenges of long-term MPA management.     

Longevity,growth, reproduction and a description of the fishery for silver sweep Scorpis lineolatus off New South Wales,Australia

Size at age, growth rates, seasonality of spawning, and size at maturity were described for the silver sweep Scorpis lineolatus off the coast of New South Wales, Australia. Estimates of age were made by counting annual zones in sections of otoliths. The ageing technique was validated using young‐of‐the‐year fish, staining fish with tetracy‐cline, and by marginal increment analysis. Silver sweep exhibited extreme longevity with an observed maximum age of 54 years and more than 50% of the fishery being greater than 15 years old. Growth was rapid during the first few years before reaching sexual maturity at 2–3 years and at a length of c. 17 cm fork length, after which growth slowed dramatically. Silver sweep displayed a winter spawning period. The fishery is unusual in that despite heavy fishing pressure and rapidly declining catches the age structure of the catch suggests a population that has been subjected to minimal fishing mortality. It is proposed that the large declines in commercial landings may be the result of serial depletion on local reefs and that current landings are being taken from schools of fish that have" receiveddate="little fishing pressure historically.     

Fishers' perceptions as indicators of the performance of Marine Protected Areas (MPAs)

How users perceive the performance of Marine Protected Areas (MPAs) is fundamental for the social acceptance of these zones. Moreover, their perceptions may be relevant for monitoring the effects of MPAs on extractive activities. This study analyzes artisanal fishers' perceptions of the performance of a north-western Mediterranean coastal MPA, which encompasses two no-take zones (NTZs). Three viewpoints have been considered: the effect on the personal activity of fishers, the effect on the local fishery and the effect on the ecosystem. In order to test the hypothesis that biomass export (spillover) - which had previously been evidenced from the two NTZs - may influence fishers' perceptions of NTZ effects, fishers' perceptions were compared with both declared and observed fishing activity over an one-year period.The results show that negative perceptions of NTZs are either nil or are negligible. Most fishers are aware of the beneficial effects of NTZs on ecosystems and fisheries. However, they remain to be convinced of the beneficial effects of the NTZs on their own activity. For instance, the proximity of a NTZ appears never to be involved in the choice of a fishing spot. This partial lack of correspondence between scientific expectation and fishers' perceptions is discussed in the light of fishing habits in the zone adjacent to NTZs, and takes into account fishing grounds, targeted species and seniority (defined as the number of years the fisher has been fishing within the MPA). All three factors appear to influence fishers' perceptions. For example, having a positive perception about a NTZ and spending more time fishing in the adjacent zone are habits that can be associated with fishers with less seniority. Fishers' perceptions obviously indicate the social acceptance of the MPA and are an essential monitoring tool for MPA managers. However, perceptions cannot be seen as a substitute for scientific monitoring, as both approaches are clearly complementary.     

The artisanal fishery of Cynoscion guatucupa in Argentina: Exploring the possible causes of the collapse in Bahía Blanca estuary

Cynoscion guatucupa Cuvier 1829 is a migratory pelagic fish species, which has a wide geographical distribution. It is the most important fishing resource for local communities in Bahía Blanca estuary and has been captured by artisanal fishermen since the 1900s. The industrial fleet has been fishing this species in the coastal area of Buenos Aires province since the 1950s, and, since 1970, landings have increased sharply. Between 2000 and 2004, the artisanal fishery in the estuarine waters of Bahía Blanca collapsed. Variations in total landings of the artisanal fleet might have arisen from the environmental variables within the estuary, fishing activity in the surrounding sea region, local pressure within the estuary and/or several other variables. Our results suggest that neither oceanographic parameters nor local pressure seem to have influenced the artisanal fishery of C. guatucupa in the estuarine region. Instead, this fishery seems to have been partially influenced by the increasing fishing pressure exerted by the industrial fishing fleet operating in open waters around the estuary. This study emphasizes the need to take into account fisheries data from both the estuarine environment and the surrounding sea region, particularly when designing management plans for the sustainable use of migrating fish resources.     

Evaluating marine protected areas for managing marine resource conflict in Hawaii

Conflict surrounding commercial fisheries is a common phenomenon when diverse stakeholders are involved. Harvesting reef fish for the global ornamental fish trade has provoked conflict since the late 1970s in the State of Hawaii. Two decades later the state of Hawaii established a network of marine protected areas (MPAs) on the west coast of the island of Hawaii (“West Hawaii”) to protect and enhance the fish resources and alleviate conflict between stakeholders, principally between commercial dive tour operators and aquarium fishers. The perceptions held by these stakeholders on West Hawaii and Maui were evaluated to understand how MPAs influenced conflict dimensions, as the former location had a well-established MPA network designed to alleviate conflict, while the latter did not. This was accomplished by analyzing the following questions: (1) perceptions about the effectiveness of MPAs to alleviate conflict and enhance reef fish; (2) perceived group encounters and threats to coral reefs; (3) willingness to encourage fishing; and (4) value orientations toward the aquarium fish trade. The results indicate the MPAs in West Hawaii were moderately effective for alleviating conflict, encounters between stakeholders occurred on both islands, dive operators strongly opposed commercial fishing and perceived aquarium fishing as a serious threat to the coral reef ecosystem, and polarized value orientations toward the aquarium fish trade confirms pervasive social values conflict. The conflict between these groups was also asymmetrical. MPAs are inadequate for resolving long term conflict between groups who hold highly dissimilar value orientations toward the use of marine resources. Future marine spatial planning and MPA setting processes should include stakeholder value and conflict assessments to avoid and manage tensions between competing user groups.     

What makes a “successful” marine protected area? The unique context of Hawaii′s fish replenishment areas

In 1998, in order to combat the degradation of yellow tang populations on the west coast of Hawaii Island, fish replenishment areas (FRAs) were established prohibiting aquarium fishing along more than thirty percent of the coastline. Unlike other marine management approaches in Hawaii, which have largely been controversial, fraught with confusion over regulations, inadequately enforced, and lacking public support, these FRAs have been lauded as a marine conservation success, with wide-ranging support and evidence of rapid replenishment of the yellow tang population. In order to better understand the contextual factors contributing to the success of the West Hawaii FRAs, this research explores the following questions: (1) What factors documented in the literature on marine protected areas (MPAs) have been demonstrated to contribute to or inhibit MPA success internationally; (2) which of these factors do the FRAs of West Hawaii exhibit; and (3) are there additional factors that may have contributed to their wide acceptance and success? Common factors contributing to MPA success are determined through a synthesis of the literature. These include: level of community engagement, socioeconomic characteristics, ecological factors, MPA design, governance, and enforcement. The outcomes of West Hawaii′s FRAs are examined in the context of these factors. While the common factors agreed upon in the literature were key to the success of the FRAs, additional contextual factors such as the unique nature of the aquarium fishery and its social marginalization also played a vital role.     

Status,trends and challenges in the sustainability of small-scale fisheries in the Philippines: Insights from FISHDA (Fishing Industries' Support in Handling Decisions Application) model

Managing small-scale fisheries in a developing country like the Philippines is very challenging because of high pressures from expanding fishing population, poverty and lack of alternative options. Thus, resource-focused fisheries management initiatives such as marine protected area (MPA) establishment will likely result in further marginalization of the poor fishers which could pose more serious problems in coastal communities. In this study, the status of small-scale fisheries in 44 coastal towns in the Philippines was assessed using FISHDA (Fishing Industries' Support in Handling Decisions Application), a simple decision support tool which requires minimal or easily-generated data. Results showed that 68% (30 out of 44) of the studied towns have unsustainable fisheries unless 58% of their fishing grounds are protected from all fishing activities. Alternatively, 53% of the active fishers in towns with unsustainable fisheries must totally stop fishing to avert fishery collapse. Alarming as it may sound, this is still an underestimate as catches incurred by the highly efficient and destructive illegal fishing activities such as blast, poison and large-scale fishing, which are reported to be still rampant in many coastal areas in the Philippines, were not accounted for in this study. This study demonstrated that MPAs alone may not be enough to avert fishery collapse even if MPA size is increased from the current 3% to 15% of the municipal waters, i.e. up to 15 km from the shore, as required by the Philippine law. Various challenges confronting the fishery and important recommendations to address them are further discussed.     

Assessment of the exploitable biomass of thread herring(Opisthonema spp.) in northwestern Mexico

In recent years, the small pelagic fishery on the Pacific northwest coast of Mexico has significantly increased fishing pressure on thread herring Opisthonema spp. This fishery is regulated using a precautionary approach(acceptable biological catch(ABC) and minimum catch size). However, due to fishing dynamics, fish aggregation habits and increased fishing mortality, periodic biomass assessments are necessary to estimate ABC and assess the resource status. The Catch-MSY approach was used to analyze historical series of thread herring catches off the western Baja California Sur(BCS, 1981–2018) and the Gulf of California(GC, 1972–2018) to estimate exploitable biomass and target reference points in order to obtain catch quotas. According to the results, in GC,the maximum biomass reached in 1972(at the beginning of fishery) and minimum biomass reached in 2015; the estimated exploitable biomass for 2019 was 42.2×10~4 t; and the maximum sustainable yield(MSY) was 15.4×10~4 t.In the western BCS coast, the maximum biomass was reached in 1981(at the beginning of fishery) and minimum biomass was reached in 2017; the estimated exploitable biomass for 2019 was 3.2×10~4 t; and the MSY was 1.2×10~4 t.Both stocks showed a decrease in biomass over the past years and were currently near to point of full exploitation.The results suggest that the use of the Catch-MSY method is suitable to obtain annual biomass estimates, in order to establish an ABC, to know the current state of the resource, and to avoid overcoming the potential recovery of the stocks.     

Global fisheries losses at the exclusive economic zone level, 1950 to present

Up to one-third of commercial fishery stocks may be overfished at present. By analyzing catch trends and applying an empirical relationship derived from stock assessments, this article tracks the geographic spread of overfishing at the country level in terms of lost catch and lost revenue, from the start of industrialized fishing in 1950-2004. The results tell a cautionary tale of serial depletion to meet the ever-rising demand for fish. Examining country losses with respect to fishery management reveals that overcapacity and excess fishing effort are widespread, but also that recent trends towards sustainability can stabilize or reverse losses (e.g. for Norway, Iceland, the US, Canada, Australia, and New Zealand). Global trade effectively masks the successive depletion of stocks, so that without decisive action to reduce fishing effort, many more stocks will suffer and undernourishment impacts for the major exporting, food-deficit nations will only magnify.     

Is catch-and-release recreational angling compatible with no-take marine protected areas?

Marine protected areas (MPAs) have become a common conservation and management tool for reducing exploitation from the commercial and recreational fisheries sectors. However, the recreational fisheries sector has the potential to be compatible with no-take MPAs when catch-and-release angling is practiced because, in theory, no fish are actually harvested. This presumes that the effects of catch-and-release angling and related activities do not cause appreciable declines in fish populations as a result of direct mortality, sub-lethal effects, or indirect effects on fish habitats, or other problems contrary to the goal of a given MPA. Here, we explore the idea that recreational catch-and-release angling may be compatible with some no-take MPAs provided there are no substantive negative ecological consequences. We argue that it is not currently possible to answer definitively the question of whether recreational catch-and-release fisheries can be compatible with no-take MPAs. Mortality rates of released fish vary extensively (between zero and near 100%) and are influenced by a number of factors including environmental conditions, fishing gear, angler behavior, and species-specific characteristics. Nevertheless, research in the field of catch-and-release is beginning to show that certain handling techniques can significantly reduce post-release mortality in fish. With appropriate regulation and angler education, catch-and-release could help enhance conservation and management goals associated with MPAs while maintaining public support and providing alternative tourism-based revenues for displaced fishers. Until sufficient data are available, research should focus on contrasting the fish community characteristics in regions with no fishing and those that permit catch-and-release fishing (i.e., opportunistic observations and controlled manipulations) as well as population-level mathematical modeling to assess the effects of angling on long-term population viability and ecosystem dynamics. Additional efforts should focus on education and outreach that provide anglers and fishing guides with the best available information to reduce catch-and-release mortality, sublethal angling-induced impairments, and broader effects on aquatic environments.     

Selected fishery and population parameters of eight shore-angling species in the Tsitsikamma National Park no-take marine reserve

An eight-year research angling dataset collected between February 1998 and December 2005 in the Tsitsikamma National Park marine protected area (MPA), along the south-eastern Cape coast of South Africa, was examined to provide estimates of important fishery and population parameters for eight important shore-angling species. Five different estimates of natural mortality (M), and the coefficients of variation (CVs) of catch per unit effort (CPUE) and size measurements were calculated. There was no consistency in estimates of M between methods, highlighting the difficulty in obtaining reliable estimates of this parameter for per-recruit assessments. The CVs of CPUE measurements were generally higher than those for size measurements. Estimates obtained for the most abundant species, blacktail Diplodus capensis, with a mean CPUE of 0.252 fish h^–1, yielded the lowest CVs for CPUE (0.806) and size (0.130) measurements. Therefore, blacktail is considered the preferred indicator species for making comparisons with estimates obtained for shore-angling fish in exploited areas and other MPAs along the South African coastline. The large inter annual variations in mean CPUE and size for all species indicated that a minimum assessment period of four years is required to obtain reliable estimates.     

Explaining global patterns and trends in marine protected area (MPA) development

The relative paucity and heterogeneous distribution of marine protected areas (MPAs) indicates the need for better understanding of factors that foster MPA establishment at local, sub-national, and national levels. The relationship between national-level MPA establishment and geographic, ecological, social, and political factors that may drive patterns and trends in MPA establishment were assessed. A country's coastline length is the strongest predictor of both the number and spatial extent of MPAs. Controlling for coastline, the Human Development Index (HDI) and spatial overlap with designated conservation priority areas are positively correlated with MPA establishment. Surprisingly, some factors influencing MPA establishment in case studies, such as percentage of fishers within a population, were not correlated with MPA establishment on a national scale. These national dynamics explain a relatively small proportion of variation, however, indicating that other biological or social factors, as well as sub-national processes, also influence MPA establishment. Positive and negative outliers illuminate the importance of policy engagement at both national and local levels. Ensuring a supportive enabling environment at the national or even multi-national level can enhance success at the local level.     

Tasmanian marine protected areas: Attitudes and perceptions of wild capture fishers

In 1999 the Marine and Marine Industries Council was established by the Tasmanian (Australia) State Government and in 2001 a Tasmanian Marine Protected Area Strategy was launched. The aims of this paper are to: investigate the views, perceptions and attitudes of commercial fishers towards this Strategy and to identify the key issues that influence fisher support or opposition to marine protected areas (MPAs). Fifty-one structured interviews with license supervisors of commercial abalone, rock lobster and scalefish fishers were conducted. Fishers stated that they would conditionally support MPAs if they sustained or increased fish populations, supported research, allowed fishing in multiple use areas, and if multiple use areas contained small ‘no-take’ zones. Fishers were concerned about the ability of the government to provide adequate marine protected area monitoring and compliance and were critical of the public consultation process that accompanied the development of the Strategy. Concern was expressed regarding the potential negative impact of additional MPAs in terms of resource sustainability and the long-term economic viability of the fishery.     

On the potential impact of harbour seal predation on the cod population in the eastern North Sea

Increasing Scandinavian harbour seal populations during the last decades coincide in time with the collapse of the cod fishery. Assumptions of a causal relationship have led to claims favouring re-introduction of seal hunting. Proposals for ‘adaptive management’ often assume that decimating seal populations will automatically favour the fishery. This argument presupposes seal predation to be sufficiently large to have a measurable impact on the fish population. The potential magnitude of the cod-seal interaction was analysed using data on harbour seal abundance, feeding habits and compiled information on cod life history and cod landing statistics. A size-structured life history matrix for the cod population was applied and the size-specific prey preferences of harbour seals were taken into account. Estimated seal predation was small compared to both the landings by the fishery, and to minimum estimates of the total cod population. Furthermore, since the size classes of cod targeted by seals have low reproductive values, the impact of seal predation on cod production will be further reduced. Our analyses suggest harbour seals have a negligible impact on the cod fishery.