Are all patterns created equal? Cooperation is more likely in spatially simple habitats

Cooperative behaviours, such as aggregation with neighbouring conspecifics, can enhance resilience in habitats where risks (i.e. predation, physical disturbances) are high, exerting positive feedback loops to maintain a healthy population. At the same time, cooperation behaviours can involve some extra energy expenditures and increasing resource competition. For sessile reefs, like mussels, simulation models predict increased cooperation under increasing levels of environmental stress. Predation risk is viewed as a behaviour‐modifying stressor, but its role on cooperation mechanisms, such as likelihood of reciprocity, has not yet been empirically tested. This study harnesses this framework to understand how cooperation changes under different perceived levels of predation risk, using mussel beds as model of a complex “self‐organised” system. Hence, we assessed the context dependency of cooperation response in different “landscapes of fear,” created by changes in predator cues, substratum availability and body size. Our experiments demonstrated that i) cooperation in a mussel bed system increases when predator cues are present, but that this relationship was found to be both, ii) strongly context‐dependent, particularly upon substratum availability and iii) size‐dependent. That is, while cooperation is in general greater for larger individuals, the response to risk results in greater cooperation when alternative attachment substratum is absent, meaning that simpler landscapes may be perceived as riskier. The context dependency of structural complexity is also an essential finding to consider in a changing world where habitats are losing complexity and cooperative strategies should be maximised.     

Does threat of mutually assured destruction produce quasi-cooperation in the mackerel fishery?

This paper uses a quarterly, game-theoretic model of the Northeast Atlantic mackerel to study the fishing strategies of five players: the EU, Norway, the Faeroe Islands, Iceland, and the international fishery on the high seas. Data on the spatial distribution of fish catches (1977–2011) are used to model changes in the distribution of the mackerel stock. The Nash equilibrium solutions predict a severe decimation of the stock through overfishing, either by parties (Iceland, the Faeroe Islands) that refuse to cooperate or by a general absence of cooperation. There is a wide discrepancy between this prediction and reality, as the stock seems, at most, only moderately overexploited, despite non-cooperation by Iceland and the Faeroe Islands. It is conjectured that these parties, and others, may engage in a degree of quasi-cooperation that falls somewhat short of full cooperation but avoids the extreme destruction of the Nash equilibrium. This tacit cooperation can be seen as being maintained by a mutually assured destruction of the fisheries of all parties in case they go to the logical extremes of non-cooperation.     

From community-based to co-management: Improvement or deterioration in fisheries governance in the Cherai Poyil fishery in the Cochin Estuary,Kerala, India?

During the last 50 years, several different forms of fisheries governance have been tried and failed in the Cochin Estuary, Kerala, India. The latest shift has been from a community-based system to a co-management system, and this paper evaluates the current system in the light of the theoretical debate over the respective merits of community-based management and co-management. The paper is based on documentary material and data from interviews carried out during fieldwork in 2004, from which it concludes that provided the co-management system incorporates community principles within it, it will be an effective form of fisheries governance.     

Exploitation and conservation of coastal and marine fisheries in Bangladesh: Do the fishery laws matter?

The present study analysed the major features of two important acts and an ordinance in Bangladesh that govern coastal and marine fishery exploitation and conservation. The problems with the implementation of these regulations were identified, and the level of compliance among fishers and reasons for their noncompliance were assessed. Based on two case studies on coastal and marine ecosystems, the findings revealed that the level of noncompliance is highly prevalent, particularly in hilsa sanctuaries in the Meghna River estuary. The study identified coastal poverty, the inadequate and improper distribution of incentives, insufficient logistic support, limited alternative occupations, political interference and a lack of awareness regarding fishery regulations as the major limitations in the implementation. The drawbacks of proper implementation and the noncompliance of fishery regulations lead to fishery degradation, directly affect the sustainability of the coastal and marine ecosystem of Bangladesh and may be barriers to achieving Goal 14 of the Sustainable Development Goals (SDGs). Establishing a co-management mechanism for sanctuary management, creating economic opportunities outside of fishery sectors, declaring more protected areas in the coastal and marine ecosystem, enhancing logistic support to the enforcing agencies and building awareness are critical to improving the compliance level among fishers. Finally, the study submits that understanding the fishers’ reasons for compliance and noncompliance of the regulations is important for devising fishery policies through the consultation and engagement of stakeholders at all levels.     

Recreational fishing and boating: Are the determinants the same?

The research uses household survey data collected from 656 people in Townsville (adjacent to the Great Barrier Reef, Australia) within a hurdle model to investigate key factors influencing both the probability of participating and the frequency of (a) boating trips which involve fishing; (b) boating trips which do not involve fishing; and (c) land-based fishing trips. The findings suggest that there are differences in determinants, highlighting the importance of disaggregating the fishing/boating and boat/land-based experience (an uncommon practice in the literature) if wishing to obtain information for use in the design of monitoring programs, policy and/or for developing monitoring and enforcement strategies relating to fishing and boating.     

Seasonal variability in the Macroinvertebrate Community Index: Are seasonal correction factors required?

Freshwater macroinvertebrate data collected from streams in Taranaki, New Zealand (1981–2006) were used to examine seasonality of biological indices including taxon richness, %EPT (Ephemeroptera, Plecoptera, and Trichoptera) richness, and the hard‐ and soft‐bottomed (‐sb) stream versions of the Macroinvertebrate Community Index (MCI). All indices tested showed modest but statistically significant seasonal variation in hard‐bottomed streams. Seasonal means for the MCI were within ±3.0% of the annual mean. The Semi‐Quantitative MCI (SQMCI) (±4.3%), %EPT richness (±7.4%) and taxon richness (±7.7%) showed greater seasonal variability than the MCI. MCI, SQMCI, and %EPT richness were significantly higher in spring and winter compared with autumn and summer. Taxon richness was lower in winter than in other seasons. In soft‐bottomed streams, SQMCI‐sb showed least seasonality (within ±3.6% of the annual mean, nonsignificant), followed by MCI‐sb and taxon richness (±4.7%), and %EPT richness (±11.2%). Spring and winter MCI‐sb and SQMCI‐sb values tended to be significantly higher than those calculated from summer or autumn samples, although most values were within 5% of the annual site means. Examination of seasonal variation in species traits and their relationships to observed seasonal patterns of biotic indices did not support the suggestion that seasonal variations in life histories of aquatic macroinvertebrates affect index values. Rather, seasons with higher biotic index values were associated with a greater frequency of flow disturbance, which is consistent with the view that the character of New Zealand's stream macroinvertebrate communities with their poorly‐synchronised life histories, has been shaped by the unpredictable physical environment. We recommend the MCI and MCI‐sb for State of Environment reporting in New Zealand for cost‐effectiveness and because data requirements and seasonal variation were less than for quantitative alternative indices. We suggest that seasonal variability is unlikely to confound interpretation, and does not need to be considered.     

Can long-term content analysis of print media be used to examine species composition,population demography and changes in distributional range of recreational fishery species?

Although marine recreational fisheries are socially and economically important, there is often limited funding for their monitoring and assessment. With South African anglers reporting catch declines for almost all targeted species and little long-term monitoring data available, novel methods need to be explored to provide managers with additional information. This study aimed to evaluate the efficacy of content analysis of print-media records for detecting long-term trends in species composition, size composition and distribution of selected recreational fishery species. Information for eight fishes captured in the marine shore-based fishery was collected from South Africa’s most popular recreational fishery magazine, between 1960 and 2009. During the five decades, there were shifts in the catch composition, from being dominated by slow-growing, large predators to faster-growing, large predators and lower-trophic-level species. There were no significant trends in the mean and maximum sizes of the dominant species, except for dusky kob Argyrosomus japonicus, which increased significantly in the maximum size reported during the study period. The distributional range of A. japonicus and leervis Lichia amia significantly increased, and that of galjoen Dichistius capensis significantly decreased. However, it was uncertain whether these trends could be attributed to population changes, changes in angler technology and/or behaviour, or climate signals. Overall, this type of content analysis may provide a cost-effective method to examine changes in species composition and fish distributions over time, but, without detailed knowledge of shifts in angler behavioural patterns, it may not be as useful for understanding changes in the population dynamics of recreational fishery species. It is suggested that fishery-independent monitoring programmes are most suited for this type of complex fishery.     

Alternatives to ITQs in equity–efficiency–effectiveness trade-offs: How the lay-up system spread effort in the BC halibut fishery

Individual Transferable Quotas (ITQs), also called “catch shares”, have been broadly adopted in the last two decades, at the same time that concerns about their equity and effectiveness in delivering the predicted outcomes have increased. This paper documents how an alternative fishermen-designed and operated system of spreading fishing effort to avoid the race for fish—called the lay-up system—worked effectively and equitably for four decades in the British Columbia halibut fishery before ITQs were introduced in this fishery. Why the lay-up system was allowed to collapse and its history ignored illustrates important roles played by conflicting ideologies, bureaucratic rationality, and the inability to imagine an alternative way of solving fisheries management problems. Trade-offs between the efficiency, equity, and effectiveness of halibut and other management systems are considered.     

Is MSC eco-labelling workable in Taiwan? Responses from various sectors of the Taiwanese sergestid shrimp fishery

Marine Stewardship Council (MSC) eco-labelling is among the widely known market-based management approaches that are considered effective in solving the problem of overfishing. The approach has been applied in several marine capture fisheries worldwide; however, it was found not to be fully workable in many fisheries for various reasons. The sergestid shrimp (Sergia lucens) fishery in Tungkang County of Taiwan has been managed well in recent decades through a bottom-up community-based co-management scheme and is probably the best candidate for obtaining the first MSC certification in Taiwan. This study assessed the fishery in relation to the three principles of MSC eco-labelling and investigated responses from experts, managers, industry representatives, and consumers on improving the fishery in order to obtain the MSC certification. The results suggested that three major problems confronted the fishery: (1) the fishery was unlikely to meet the MSC standards unless it could reduce its high bycatch rate; (2) the economic and/or political benefits were not attractive enough to the relevant sectors for them to cover the high costs and responsibility of obtaining and maintaining the MSC certification; and (3) the fishery was reputed to be well managed without any eco-label, suggesting no strong incentive to obtain one from a management perspective. The benefits of MSC eco-labelling could be consolidated, however, and the role of government was crucial in this regard.     

The Magnuson-Stevens act (1976) and its reauthorizations: Failure or success for the implementation of fishery sustainability and management in the US?

The Magnuson-Stevens Fishery Conservation and Management Act (1976), opened a new era of federal fishery management in the United States. It was enacted primarily to establish a system for conserving and managing fisheries in the new 200-mile (EEZ). The US assumed exclusive authority for managing all fisheries within the EEZ, except for highly migratory species such as tunas and billfishes. Within the framework of the Act, eight Regional Fishery Management Councils (Regional Councils) were created, which are responsible for preparing Fisheries Management Plans (FMPs) in federal waters under their jurisdiction. Each FMP must meet a series of National Standards (NSs) for conservation and management. The Act was reauthorized in 1996 with the passage of the Sustainable Fisheries Act (SFA), which aimed at fine tuning the fishery regulatory apparatus that was established under the original Act. This "fine tuning" involved increased attention to biological concerns, and removal of ambiguities within it. The Act was reauthorized again in 2007, mainly to provide for more clear directives and regulations to end overfishing. After more than thirty years since the Act was passed into law, the debate among conservationists, commercial and recreational fishery representatives, and politicians on the effectiveness of the Act in achieving its purported goals it still continues. Is the Act delivering on its promises? Do NSs reflect the most important priorities for the US fishery resources, conservation and sustainable exploitation? Do the Regional Councils represent all parties that should be involved in the fisheries resources management? The aim of this paper is to provide a critical analysis to answer these questions. This paper begins with a review of the Act and its background, followed by discussion and analysis of the Act's benefits and flaws. Finally, suggestions for the implementation of its structure and future directions in fishery management strategies are made.     

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.     

Does beach seine fishery permanently alter macroinvertebrate communities and sediment characteristics in the Southern Caspian Sea?

The impacts of a beach seine fishery on macroinvertebrate communities and sediment characteristics were investigated in the Southwest Caspian Sea. Samples from a single impacted site that was regularly seined were compared with two control sites outside the fishing area. Benthic macroinvertebrates were sampled on four occasions: 6 months prior to the opening of the beach seine fishery (Time 1), 1 day immediately after the closing of beach seining (Time 2), 1 week after closing (Time 3), and 1 month after closing (Time 4). No significant differences were detected in total density, Shannon diversity, or evenness of the macroinvertebrate assemblages between impact and control sites. Unlike density, species richness increased significantly immediately after fishery closure at all sites. A significant difference was detected in the number of species between Time 2 and Time 3 at all sites and the number of species was reduced at Time 4 in all sites. Pontogammarids increased by twofold in the impact site 1 day immediately after closing beach seine fishery and leveled off toward the end of the closed season. The amplified density of pontogammarids 1 day after fishery closing at the impact site might be driven in part by an increase in sediment oxygen content resulting from disturbance of the sea floor. An alternative explanation is that the effect of fish predation on pontogammarids has largely been minimized at the impact site after 6 months of continuous fishing activity. No significant changes in the sedimentary organic content and chlorophyll‐a between the impact and control sites were observed during the courses of sampling; however, a significant change occurred between the average sedimentary pheopigment content of the control sites and that of the impact site. The conclusion from the present study is that beach seine fishery does not harm to benthic communities. The closed season also seemed to allow recovery to pre‐season levels of macroinvertebrate richness and sedimentary chlorophyll‐a.     

Fishermen facing the commercial lobster fishery licensing policy in the Canadian Maritime Provinces: origins of illegal strategies, 1960–2000

Illegal practices of marketing licences and holding multiple Lobster licences have been developed through time by fishermen in the Maritimes Provinces of Canada. The consequences of these practices have an impact on fishing activity that interferes with management goals and efficiency and threatens social organisation of fishing community. This article shows their development through the back and forth movement between the building of limited entry policy and fishermen's responses to it since the introduction of limited entry to the Canadian lobster fishery in 1967. Recent changes to American limited entry policies in Massachusetts and the Maine have attempted avoided some of the problems experienced in Canada.     

Are midwater shrimp trapped in the craters of submarine volcanoes by hydrothermal venting?

The biology of Kick’em Jenny (KEJ) submarine volcano, part of the Lesser Antilles volcanic arc and located off the coast of Grenada in the Caribbean Sea, was studied during a cruise in 2003. Hydrothermal venting and an associated biological assemblage were discovered in the volcanic crater (∼250 m depth). Warm water with bubbling gas emanated through rock fissures and sediments. Shrimp (some of them swimming) were clustered at vents, while other individuals lay immobile on sediments. The shrimp fauna consisted of 3 mesopelagic species that had no prior record of benthic or vent association. We suggest that these midwater shrimp, from deeper water populations offshore, were trapped within the crater during their downward diel vertical migration. It is unknown whether they then succumbed to the hostile vent environment (immobile individuals) or whether they are potentially opportunistic vent residents (active individuals). Given the abundance of submarine arc volcanoes worldwide, this phenomenon suggests that volcanic arcs could be important interaction sites between oceanic midwater and vent communities.     

Molluskan species richness and endemism on New Caledonian seamounts: Are they enhanced compared to adjacent slopes?

Seamounts were often considered as ‘hotspots of diversity’ and ‘centers of endemism’, but recently this opinion has been challenged. After 25 years of exploration and the work of numerous taxonomists, the Norfolk Ridge (Southwest Pacific) is probably one of the best-studied seamount chains worldwide. However, even in this intensively explored area, the richness and the geographic patterns of diversity are still poorly characterized. Among the benthic organisms, the post-mortem remains of mollusks can supplement live records to comprehensively document geographical distributions. Moreover, the accretionary growth of mollusk shells informs us about the life span of the pelagic larva. To compare diversity and level of endemism between the Norfolk Ridge seamounts and the continental slopes of New Caledonia we used species occurrence data drawn from (i) the taxonomic literature on mollusks and (ii) a raw dataset of mainly undescribed deep-sea species of the hyperdiverse Turridae. Patterns of endemism and species richness were analyzed through quantitative indices of endemism and species richness estimator metrics. To date, 403 gastropods and bivalves species have been recorded on the Norfolk Ridge seamounts. Of these, at least 38 species (∼10%) are potentially endemic to the seamounts and nearly all of 38 species have protoconchs indicating lecithotrophic larval development. Overall, our results suggest that estimates of species richness and endemism, when sampling effort is taken into account, were not significantly different between slopes and seamounts. By including in our analyses 347 undescribed morphospecies from the Norfolk Ridge, our results also demonstrate the influence of taxonomic bias on our estimates of species richness and endemism.     

Lost in translation? Standardising the terminology used in marine invasion biology and updating South African alien species lists

Confusion between terms and ambiguities among definitions have long plagued the field of invasion biology. One result is disruption in flow of information from researchers to policy-makers and managers who rely on science to inform regulatory frameworks and management actions. We reviewed the South African marine biology literature to quantify the current usage of terminology describing marine invasions and found a variety of terms in use, few of which are defined when used. In response, we propose standard terminology that aligns with international practice. We then interpreted the Blackburn unified framework for biological invasions within the marine context and used this as a transparent way to apply the standardised terms to an updated list of marine alien species for the country. This resulted in the recognition of 36 alien and 53 invasive species within South Africa. Most notably, follow-up research is required to confirm the status of at least 11 listed species, the majority of which have been recorded only once, or not in the past 25 years. It is hoped that by standardising terminology, marine science in South Africa will better support authorities charged with managing the threat posed by marine alien species.     

The whelk (Buccinum undatum L.) in the western Dutch Wadden Sea in the period 1946–1970: Assessment of population characteristics and fishery impact

In the Dutch Wadden Sea a whelk fishery existed from 1900 to 1970. The high post-war catches, following a period without fishery, and the subsequent decrease in catches when fishery was reopened, allowed us to estimate fishery mortality and recruitment. Information on natural mortality and growth, which were required in the estimation procedure, was obtained from previous studies elsewhere. Natural mortality could be calculated from an experiment with marked whelks in the Thames estuary. Age-length relations could be used from French investigations on whelks near the Channel Islands. The size of a potential whelk population could be estimated. Effects of fishery and possible causes of the disappearance of the whelk from the Dutch Wadden Sea are discussed.     

The marine ecosystem off Peru: What are the secrets of its fishery productivity and what might its future hold?

The marine ecosystem located off the coast of central and northern Peru has stood as the “world’s champion” producer, by far, of exploitable fish biomass, generally yielding more than 20 times the tonnage of fishery landings produced by other comparable regional large marine ecosystems of the world’s oceans that operate under similar dynamic contexts and are characterized by comparable, or even greater, basic primary production. Two potentially contributing aspects are discussed from a framework of interregional comparative pattern recognition: (1) the advantageous low-latitude situation that combines strong upwelling-based nutrient enrichment with low wind-induced turbulence generation and relatively extended mean “residence times” within the favorable upwelling-conditioned near-coastal habitat and (2) the cyclic “re-setting” of the system by ENSO perturbations that may tend to interrupt malignant growth of adverse self-amplifying feedback loops within the nonlinear biological dynamics of the ecosystem.There is a developing scientific consensus that one of the more probable consequences of impending global climate changes will be a general slowing of the equatorial Pacific Walker Circulation and a consequent weakening of the Pacific trade wind system. Since the upwelling-favorable winds off Peru tend to flow directly into the Pacific southeast trade winds, a question arises as to the likely effect on the upwelling-producing winds that power the productivity of the regional coastal ecosystems of the Peru–Humboldt Current zone. It is argued that the effects will in fact be decoupled to the extent that upwelling-favorable winds will actually tend to increase off Peru. Data demonstrative of this decoupling are presented. A tendency for less intense El Niño episodes in the future is also suggested. These conclusions provide a framework for posing certain imponderables as to the future character of the Peruvian marine ecosystem and of the fisheries it supports.     

An early footprint of fisheries: Changes for a demersal fish assemblage in the German Bight from 1902–1932 to 1991–2009

Groundfish survey data from the German Bight from 1902–08, 1919–23, and 1930–1932 and ICES International Bottom Trawl Survey (IBTS) quarter 3 data from 1991 to 2009 were analysed with respect to species frequencies, maximum length, trends in catch-per-unit-effort, species richness parameters (SNR) and presence of large fish (Φ₄₀), the latter defined as average presence of species per haul with specimens larger than 40 cm given. Four different periods are distinguished: (a) before 1914 with medium commercial CPUE and low landings, Φ₄₀ ≈ 2, high abundance in elasmobranchs and SNR conditions indicating highly diverse assemblages, (b) conditions immediately after 1918 with higher commercial CPUE, recovering landings, Φ₄₀ at > 4 in 1919, and SNR conditions indicating highly diverse assemblages, (c) conditions from 1920 to the early 1930's with decreasing commercial CPUE, increased landings, decreasing Φ₄₀, SNR conditions similar to later years indicating less diverse assemblages, and a decrease in elasmobranchs. In the IBTS series (d), Φ₄₀ remains low indicating an increased rarity of large specimens, and SNR characteristics are similar to the third period. Dab, whiting and grey gurnard have increased considerably in the IBTS series as compared to the historic data. Φ₄₀ is suggested an alternative indicator reflecting community functional diversity when weight based indicators cannot be applied.