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Knowledge on the spatial and temporal distribution of the activities carried out in the marine environment is key to manage available space optimally. However, frequently, little or no information is available on the distribution of the largest users of the marine space, namely fishers. Tracking devices are being increasingly used to obtain highly resolved geospatial data of fishing activities, at intervals from seconds to minutes. However, to date no standardized method is used to process and analyse these data, making it difficult to replicate analysis. We develop a workflow to identify individual vessel trips and infer fishing activities from highly resolved geospatial data, which can be applied for large-scale fisheries, but also considers nuances encountered when working with small-scale fisheries. Recognizing the highly variable nature of activities conducted by different fleets, this workflow allows the user to choose a path that best aligns with the particularities in the fishery being analysed. A new method to identify anchoring sites for small-scale fisheries is also presented. The paper provides detailed code used in each step of the workflow both in R and Python language to widen the application of the workflow in the scientific and stakeholder communities and to encourage its improvement and refinement in the future. [ABSTRACT FROM AUTHOR]

About a third of all marine fish in the world are caught in Small-Scale Fisheries (SSF). SSF are increasingly recognised as essential for food security and livelihoods for vulnerable and economically fragile communities globally. Although individual SSF vessels are usually perceived as having little impact on the ecosystem, the cumulative impact of gear type and number of vessels may be substantial. Bottom trawling is a common fishing method that can greatly influence the marine ecosystem by damaging the seafloor and generating high levels of discards. However, appropriate sampling coverage using on-board observer programmes to collect these data from SSF are rare, as they are expensive and pose logistical constraints. A mobile App was used to assess whether self-reporting by fishers could provide reliable fine-scale information on fishing effort and discards over time in an illegal shrimp trawling fishery in northern Peru. Maps depicting the spatial distribution of trawling effort and the proportion of discards from observers and fishers were compared using the Similarity in Means (SIM) Index, which ranges from 0 when spatial patterns differ completely to 1 when spatial patterns are very similar. High levels of agreement between spatio-temporal patterns of effort (SIM Index = 0.81) and discards (0.96) were found between fisher and observer maps. Moreover, far greater spatial coverage was accomplished by fishers, suggesting that self-reporting via an App represents a useful approach to collect reliable fisheries data as an initial step for effective monitoring and management of these fisheries. [ABSTRACT FROM AUTHOR]

• Highly-resolved vessel tracking data provide reliable indicators of fishing effort. • For passive gears, spatial indicators outperform time at sea indicators of fishing effort. • Gear soak time can be reliably estimated from vessel tracking data. • Suitable indicators are needed to appropriately represent fishers in marine spatial planning. Increasing competition for marine space requires the appropriate development of indicators to best represent the use of marine areas and the value (whether economic, social and/or cultural) derived from such use. Fishers (the largest group of users) are often under-represented in marine spatial planning processes. Highly-resolved vessel tracking data provide opportunities to map the activities of fishing vessels at a level of detail never before available. Most effort mapping methods have focused on active gears such as trawls or dredges in large scale fisheries. For these fisheries, the time spent fishing at sea (hours) is usually a representative indicator of fishing effort, enabling a straightforward mapping of the most important fishing grounds. However, for passive gears generally used in small-scale fisheries, we show that spatial indicators of effort (here, length of vessel track) greatly outperform time-at-sea as an indicator of fishing effort. We further demonstrate and validate a method to estimate gear soak time from vessel tracking data and show how maps of effort that account for soak time can be different from those solely based on time spent fishing at sea. The development of adequate methods to quantify the spatial distribution of passive gear effort is particularly relevant to fisheries management because globally about a fifth of all catches (by weight) are landed by passive gears. Appropriate, fine scale effort maps will provide better tools for spatial planning to support sustainable fishing. [ABSTRACT FROM AUTHOR]

Around 4.2 million tonnes of fish and other species, some of which are of conservation concern, are discarded every year in bottom trawl fisheries. This study focusses on a small-scale shrimp trawl fishery located in northern Peru that operates with high level of discards which causes conflict with other local fishers. Despite trawling being an illegal activity within the 5NM off the coast, this fishery has been operating in these inshore areas for over 40 years because it sustains the well-being of hundreds of fishers. This study aimed to identify the factors that affect the spatio-temporal variation in catches in order to propose recommendations that can be adopted by fishers to minimise their impact on the ecosystem while still providing economic opportunities. The spatial distributions of shrimp, main commercial species and discards were modelled over time using hierarchical generalised additive models. Strong spatio-temporal variation was observed for all catch components and moon phase affected commercial species and discards differently. The results show that, to reduce the environmental impacts of this fishery in the short-term, the fishing area could be divided into north and south and that fishing activities should be limited to the southern area in the autumn. Other recommendations rely on temporal closures during the week of the first quarter of the moon phase. Finally, considering the institutional weaknesses in monitoring, control and surveillance, we suggest that the only realistic approach to reduce the fishery's environmental impacts in the short-term is to foster the willingness of fishers to adopt responsible fishing practices. Yet, long-term solutions will require comprehensive co-management efforts. [ABSTRACT FROM AUTHOR]

Most marine invertebrates experience variable environments and for broadcast spawners, fertilisation success increases with greater synchronisation of spawning, so a capital breeding strategy is predicted. However, this prediction should be tested for species with protracted breeding seasons, since it is not clear how reproduction is fuelled over several consecutive months of spawning. The simultaneous hermaphrodite scallop Pecten fumatus was used to test the hypothesis that protracted spawning is supported by both capital and income strategies, depending on the state of energy reserves and food availability at the time of oocyte maturation. The study was carried out in Great Bay, Tasmania, Australia (147.335W, 43.220S) in 2010/2011. The use of glycogen, protein and lipid in the muscle, gonad, and digestive gland was examined, along with the role of atretic eggs as an alternative energy source for oogenesis and maturation. The reproductive stage of an individual was determined using only the ovaries. P. fumatus uses a capital breeding strategy early in the reproductive cycle during winter and spring (August-October) with muscle glycogen and protein and digestive gland lipid providing energy for oogenesis. Given there was no evidence of energy stores being used later in the reproductive cycle in late spring and summer (November-March), when less food was available for direct fuelling of reproduction, it appears that metabolites produced from oocyte lysis may have fuelled oogenesis. Recycling of energy from oocyte resorption must be considered as part of the strategy of energy use to fuel reproduction in marine invertebrates. [ABSTRACT FROM AUTHOR]

Early post-settlement mortality is one of the main processes determining distribution and abundance patterns of marine benthic invertebrates. Most scallops have an attached phase as spat before they release the byssus and move onto the soft sediments. Thus, spat differ from other stages of life in their use of microhabitat, lack of mobility, and therefore in their vulnerability to mortality processes such as predation. However, the contribution of predation to explain levels of mortality experienced by spat and early juvenile scallops is unknown. Complex habitats such as seagrasses and algae provide a substrate upon which spat can attach and might confer an advantage as a refuge from predation. This study investigates the contribution of early post-settlement predation on abundance of Pecten fumatus and determines the role of the algae Hincksia sordida as a refuge from predation. Data were collected using field observations, a predator exclusion experiment, and tethering techniques. Mortality of up to 85% during the first weeks after settlement appeared to have prevented the establishment of an adult population at our study site. Mats of the macroalgae H. sordida provided a settlement substrate for P. fumatus spat. However, increased algal biomass did not provide greater protection from predation to juvenile scallops than lower algal biomass. Our study suggests that prey survival in submersed vegetation is likely to be dynamic among years, and affected by prey behaviour and density as well as the characteristics of the submerged vegetation. [ABSTRACT FROM AUTHOR]

In broadcast spawners, low densities and poor spawning synchronization can reduce fertilization success. In wild populations, individuals in close proximity tend to spawn more synchronously than those further apart, suggesting that low spawner densities may reduce gamete production by lessening the efficacy of pheromone signalling. This study assessed the role of adult density in aggregation patterns and spawning synchronization in a semi-sessile, hermaphroditic scallop, Pecten fumatus. The study was carried out in Great Bay, Tasmania, Australia (147.335 W, 43.220 S) in 2010-2012 by assessing (1) the relationship between density, small-scale aggregation patterns and nearest neighbour distance (NND), (2) the temporal pattern of spawning synchronization, and (3) the effect of site density and conspecific proximity on the probability of spawning. Densities observed in the field ranged from 1.455 to 0.021 ind m. Sites with lower densities had less small-scale aggregation and greater NNDs. Patterns of small-scale aggregation and NNDs in P. fumatus were comparable to those observed in a gonochoristic species. Spawning synchronization was highly variable, ranging between 3.5 and 59.8 % of individuals spawning. P. fumatus was more likely to engage in spawning activity when at greater densities and at closer proximity to conspecifics. This strongly suggests that lower densities in this scallop reduce not only the number of individuals contributing to the production of gametes, but also reduces the synchronization of spawning. [ABSTRACT FROM AUTHOR]

Abstract: Variable and declining catches, high prices and a growing demand have raised interest in the cultivation of penshells in Mexico, and recent studies showed that Atrina maura has fast growth rates and is a potential candidate for aquaculture in Baja California Sur. This study aimed to generate more information on growth, production and mortality of A. maura and to evaluate if a low cost intertidal bottom culture can be economically feasible. Wild specimens were planted into two plots at two different tide levels in a mangrove channel called Estero San Buto, in Bahia Magdalena, Baja California Sur, Mexico. From September 2007 to May 2008, size increment data was recorded monthly, as well as weight, mortality and environmental conditions. From the data obtained and interviews with aquaculturists about costs and potential benefits, a bioeconomic model was constructed to evaluate the profitability of the investment. Growth data from A. maura was fitted to the specialized Von Bertalanffy model, a fixed L∞ =33.5 was used and the growth parameters were calculated as K=0.48 and 0.35 for the lower and mid-intertidal, respectively. Muscle and gonad condition indices showed significant correlations with temperature. Gonad maturation of A. maura initiated from January to March and the main spawning season started at the end of March. Survival after transplantation from suspended trays was high (99%) and after eight months of culture the average survivorship was 78%. The bioeconomic model simulating a 14year culture operation showed that the main costs were related to labor and that the capital equipment costs were high during the first and eighth year, due to the lifespan of Nestier trays. A batch of 200,000 seeds each year was needed to achieve positive returns under the study conditions, with a payback period of seven years. The higher risk associated with longer periods of culture would probably discourage fishermen from this type of investment. The study highlights the importance of considering economic aspects before committing to this type of venture. [Copyright &y& Elsevier]

This paper makes a case for revisiting the understandings of translation to enhance the co-production of geographical knowledge on climate change. Specifically, it offers insights about the potential role that schoolteachers and students can have as knowledge producers in relation to climate change by drawing on a case study of collaborative research on El Niño in Sechura, northern Peru. We call for researchers to pay greater attention to how co-production can be achieved through the integration of research agendas and practice with curricula development and innovation in school education. We contribute to work on how a generational shift in understanding about climate adaptation can be achieved through exploring communities' knowledge of the lesser-known opportunities of the El Niño phenomenon in northern desert regions. We conclude by arguing that revisiting how geography engages in and with translation is an urgent priority in climate-challenged times. [ABSTRACT FROM AUTHOR]