Academic literature on the topic 'Crustacean Fisheries'
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Journal articles on the topic "Crustacean Fisheries"
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Arkham, M. Nur, Arif Trihandoyo, and Agus Ramli. "SMALL SCALE FISHERIES AND CRUSTASEAN RESOURCES LINKAGES IN NORTH MADURA WATERS: SOCIAL-ECOLOGICAL CONNECTIVITY STUDIES." Coastal and Ocean Journal (COJ) 2, no. 1 (November 3, 2017): 1–10. http://dx.doi.org/10.29244/coj.2.1.1-10.
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Crustaceans is a fishery resource that has high economic value, where a lot of demand for exports from crustacean group. Small-scale fisheries have become the foundation for the fishermen who live in coastal areas. The purpose of this study is to identify the resource utilization of crustaceans by small-scale fisheries in North Madura Waters, and assess dependency on the existence of small-scale fisheries resources existing crustaceans in North Madura Waters. The research method is direct observation, interviews, and free dialogue with some of the respondents. The results that have been obtained from this study, so it can be concluded that small-scale fishermen who make arrests crustacean resources in North Madura Waters is fishing with fish traps and fishing gear dogol that land their catch in PPI Kranji, Sampang PPI and PPI Tamberu. Dominant Commodities catch is crabs, tiger shrimp and white shrimp. The results of the small-scale fisheries dependence on resources from the index dependence crustaceans seen mention that fishermen who landed the catch in PPI Kranji, Sampang PPI and PPI Tamberu have a resource dependency with crustaceans with an index value of 21.74; 13.87; and 0.42.
Keywords:
crustacea, small scale fisheries, dipandance crustacea index, North Madura Waters
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Saputra, Merdeka Agus. "Moving within and beyond illegal crustacean fishery: why do Indonesian fishermen not comply with the crustacean catch ban rule?" Maritime Studies 19, no. 4 (August 18, 2020): 457–73. http://dx.doi.org/10.1007/s40152-020-00194-y.
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AbstractIllegal wild capture fisheries undermine crustacean (e.g., crabs, lobsters, and swimming crabs) stock and their habitats. In a search for a new approach to the fisheries issues, this paper aims to explain why the illegal fishing for crustacean species still exists in Indonesia. It focuses on analyzing a set of practices in crustacean production and consumption. Banyuwangi (Indonesia) was the case study area of the conducted fieldwork. The method applied semi-structured interviews and participant observation. The design of research enabled the researcher to study daily fishing, purchasing, and processing. These practices determined the exploitation of crustacean species in the sea. This paper shows that the current fishing, purchasing, and processing of crabs, swimming crabs, and lobsters played a vital role in constructing the habit of illegal fishing. When the catch prohibition rules heavily focused on the wild capture fisheries in the sea, the local intermediaries and processors innovated their purchasing and processing to obtain crustacean species incessantly. Such an innovation was in response to the crustacean scarcity problems. (1) In swimming crab mini-plants, processors diversified their processed swimming crab products. The crab product diversification allowed them to process swimming crabs in all sizes. (2) The local intermediaries gave fishermen binding loans. Fishermen paid back the loans by supplying the crustacean species to the loan givers. (3) The existence of processing and purchasing stimulated fishermen to harvest every last crustacean species. Even though such crustacean fishing was illegal, it contributed to the livelihoods of fishermen, local intermediaries, and processors. This paper makes a research contribution to the use of social practice theory in fisheries issues. It gives a novel research approach to the habit of illegal fishing problems.
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Tully, Oliver, Juan Freire, and Julian Addison. "Crustacean fisheries." Fisheries Research 65, no. 1-3 (December 2003): 1–2. http://dx.doi.org/10.1016/j.fishres.2003.09.003.
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Wanjiru, Caroline, Sonja Rueckert, and Mark Huxham. "Composition and structure of the mangrove fish and crustacean communities of Vanga Bay, Kenya." Western Indian Ocean Journal of Marine Science 20, no. 2 (February 2, 2022): 25–44. http://dx.doi.org/10.4314/wiojms.v20i2.3.
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Mangroves support coastal fisheries, particularly by providing nurseries for juvenile fish. However, much remains unknown about the fish and crustacean communities in mangroves and about the lifecycles and behaviours of individual species. This study is the first to describe the fish and crustacean communities in the Vanga mangrove ecosystem, the largest mangrove forest and the most important marine fisheries landing site in southern Kenya. Using fyke nets, 14 mangrove creek sites were sampled once every 3 months during spring tides, between September 2015 and September 2017. The sampling period covered the north east (NEM) and south east (SEM) monsoon seasons. A total of 1,879 fishes and 1,132 crustaceans were caught, represented by 59 and 16 species, respectively. Over 95 % of the fishes caught were juveniles with 50 % of both fish and crustacean species being of commercial importance. About 70 % of the catch was dominated by only 6 fish species with Yarica hyalosoma and Acropoma japonicum contributing 44 % of the total abundance. Penaeus semisulcatus and Penaeus indicus dominated the crustaceans. Fish abundances differed significantly between seasons, with the SEM catches almost three times higher than those in the NEM, while crustaceans displayed no clear seasonality. The study documents for the first time the fish and crustacean communities in Vanga mangroves and confirms their importance as juvenile habitat for commercial species. The importance of mangrove and near mangrove habitat as nursery habitat for both fish and crustaceans emphasizes the need for conservation particularly of seaward edges
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Caddy, J. F. "Modelling Stock–Recruitment Processes in Crustacea: Some Practical and Theoretical Perspectives." Canadian Journal of Fisheries and Aquatic Sciences 43, no. 11 (November 1, 1986): 2330–44. http://dx.doi.org/10.1139/f86-285.
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Several approaches toward development of stock and recruitment models for exploited crustacean populations are reviewed. Such approaches include modifications of classical stock–recruitment models, or ones more directly related to crustacean biology. The latter are believed to offer the most promise for practical application. Standard yield per recruit models using continuous growth functions have been applied to crustacean stocks, but moult increment – frequency versions of yield per recruit calculations better reflect the discrete growth in crustaceans and changes in growth on maturity. They can be extrapolated easily to calculate fecundity per recruit and assess the impact of exploitation on spawning potential. Simple, semiquantitative approaches, such as life history tables, promote investigation of hypotheses of growth, mortality, maturity/fecundity, and harvesting strategy on management, but like yield per recruit models, cannot easily take into account density-dependent recruitment. We may look forward to the development of models that take into account the nature of crustacean life histories, reflecting the need for cross-scheduling of growth and reproduction in environmentally limiting conditions. Modelling life history processes in biological time units related to moult cycle duration, and cross-converting to real time for consideration of the fisheries component, should offer a notable simplification of the modelling process. The existence of several "choices" for an individual crustacean at different points in the moulting/reproduction cycles makes cohort models cumbersome and seems to require the adoption of a stochastic approach, for instance Markov-related processes, which better take into account complexities of biology and fishery-related processes. For many crustaceans, recruitment is believed to be subject to a "bottleneck" somewhere subsequent to the early larval stages, and identification of the species niche for postlarval stages could be of great practical importance for management and stock enhancement. The concept of the fractal surface as a postlarval and juvenile habitat is suggested as a promising approach, and an expression for natural mortality at size is derived for obligate crevice dwellers on a fractal surface. In relatively few circumstances for Crustacea have density-dependent factors been demonstrated in the field as affecting spawning success and the survival to recruitment of postlarval and juvenile stages. Recruit survival appears to be dominated by environmental conditions that vary significantly; seasonal timing of larval release depending on environmental change from year to year. Short-cutting the investigation of precise impacts of stock density, fishing effort, and environment on recruitment can be achieved using production models, delayed recruitment models, models with autoregressive terms, or production models using mortality rates, where effort definition is difficult and catchability a function of behaviour and environnment. The overriding influence of environment on recruitment success is illustrated for both short- and long-lived species in the tropics and northern latitudes, and this is especially true for high unit value Crustacea resources whose heavily exploited fisheries generally operate at low spawning stock sizes. Fluctuating predator density, or other multispecies interactions, affect recruitment and available number of niches, and modelling of trophic relationships has promise. The range of possible models corresponds to various degrees of refinement of the data base, and the importance of biotic, abiotic, and geographical factors in controlling crustacean recruitment is stressed. Also of fundamental importance are the economics of exploitation of species with a high and elastic demand, which results in high actual and latent levels of effort, fisheries heavily dependent on incoming year-classes, and serious problems in maintaining exploitation rates at reasonable levels.
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Pratama, Andika Resa, Abdul Hamid, Syamsul Kamri, and Rahmad Sofyan Patadjai. "Diversity of Crustaceans Bycatch of Blue Swimming Crab (Portunus pelagicus) Fisheries of Landed in Leppe village, Soropia District, Konawe Regency." Journal of Tropical Fisheries Management 6, no. 2 (December 16, 2022): 95–102. http://dx.doi.org/10.29244/jppt.v6i2.43801.
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This research was aiming of find out the diversity of crustaceans bycatch of blue swimming crab (Portunus pelagicus) fisheries of moon period based. The method used was a survey method and sampling of crustacean bycatch was carried out during the period of bright moon (11-15 moon nights) and dark moon (27-1 moon nights). The results showed that there were 20 species of crustacean bycatch found during the study in which 17 species were found during the bright moon and 16 species were found during the dark moon. Thalamita danae species had the highest abundance during the dark and the bright moon period. The number of the male crustaceans bycatch was higher than the females for both bright and dark moon periods.Diversity index crustacean bycatch in both periods (brigh tand dark) ranged from 0.83 to 0.85. The evennes index and dominance index inthe bright and dark moon are the same (0.69 and 0.22, respectively).
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Boenish, Robert, Jacob P. Kritzer, Kristin Kleisner, Robert S. Steneck, Karl Michael Werner, Wenbin Zhu, Frederick Schram, et al. "The global rise of crustacean fisheries." Frontiers in Ecology and the Environment 20, no. 2 (November 15, 2021): 102–10. http://dx.doi.org/10.1002/fee.2431.
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Smith, Michael T., and Julian T. Addison. "Methods for stock assessment of crustacean fisheries." Fisheries Research 65, no. 1-3 (December 2003): 231–56. http://dx.doi.org/10.1016/j.fishres.2003.09.017.
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Jimenez-Gutierrez, Stephanie, Cristian E. Cadena-Caballero, Carlos Barrios-Hernandez, Raul Perez-Gonzalez, Francisco Martinez-Perez, and Laura R. Jimenez-Gutierrez. "Crustacean vitellogenin: a systematic and experimental analysis of their genes, genomes, mRNAs and proteins; and perspective to Next Generation Sequencing." Crustaceana 92, no. 10 (October 23, 2019): 1169–205. http://dx.doi.org/10.1163/15685403-00003930.
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Abstract Crustacean vitellogenesis is a process that involves Vitellin, produced via endoproteolysis of its precursor, which is designated as Vitellogenin (Vtg). The Vtg gene, mRNA and protein regulation involve several environmental factors and physiological processes, including gonadal maturation and moult stages, among others. Once the Vtg gene, mRNAs and protein are obtained, it is possible to establish the relationship between the elements that participate in their regulation, which could either be species-specific, or tissue-specific. This work is a systematic analysis that compares the similarities and differences of Vtg genes, mRNA and Vtg between the crustacean species reported in databases with respect to that obtained from the transcriptome of Callinectes arcuatus, C. toxotes, Penaeus stylirostris and P. vannamei obtained with MiSeq sequencing technology from Illumina. Those analyses confirm that the Vtg obtained from selected species will serve to understand the process of vitellogenesis in crustaceans that is important for fisheries and aquaculture.
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Mandal, Ram B., and Sarada Paudel. "Bacterial and Crustacean Diseases Reported from Fishes Cultured in Ponds of Begnas, Pokhara, Nepal." ZOO-Journal 5 (December 31, 2019): 64–67. http://dx.doi.org/10.3126/zooj.v5i0.34785.
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Present study surveyed fish diseases in ponds of Begnas area in Pokhara Valley, Nepal. The fishes were collected with the help of the local fishermen and were examined under compound microscope in the laboratory of Pokhara Fisheries Research Centre, Begnas. Two fish diseases, Tail rot and Arugulosis were reported of which later was dominant.
Dissertations / Theses on the topic "Crustacean Fisheries"
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Che, Harun Hasnita Binti. "Molecular ecology of two commercially important crustacean species, Nephrops norvegicus and Macrobrachium rosenbergii : implications for the management of fisheries and aquaculture." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/4101/.
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Molecular ecology is one of the most important branches of evolutionary biology, and it uses the advantages of molecular techniques such as PCR-RFLP, sequencing, microsatellite analysis, and most recently the introduction of next generation sequencing, to address outstanding issues in the fields of population genetics and phylogeny. The genomic approach has been influential in providing new information relevant to traditional questions in ecology, such as genetic differentiation, speciation, species adaptation and others. The rationale of the present thesis was to incorporate the advantages of both the PCR-RFLP and sequencing techniques to gain information on the genetic variability of two commercially-important crustacean species, namely the Norway lobster Nephrops norvegicus and the giant freshwater prawn Macrobrachium rosenbergii. Nephrops norvegicus exhibits large morphological variability even between adjacent populations. The first objective of this thesis was to investigate the genetic variability of N. norvegicus from three localities, the Clyde Sea area and North Minch (North Sea) as well as Icelandic waters. The phylogeographic study found no significant differentiation between populations from the studied areas (FST: 0.01819). This finding is consistent with outcomes from previous studies that N. norvegicus populations were not geographically structured. Outcomes from the present study strongly suggest that environmental factors, rather than genetic factors, are more likely to play a more significant role in the high morphological differentiation observed in this species. A study of the most important freshwater crustacean species, Macrobrachium rosenbergii was then undertaken as a contribution to understanding the most complex biogeography in the world, the Indo Australian Archipelago (IAA). The IAA has incredible species richness and endemism and is the location of 4 out of 25 world’s biodiversity hotspots, namely the Sundaland, the Philippines, Indonesia and Wallacea. Within the IAA is the location of Wallace’s line and Huxley’s line, the most abrupt faunal transition in the world that lies between the Sunda and Sahul shelves. The studied species used in the present thesis, M. rosenbergii is an ideal model species as it has a wide geographical distribution across the IAA. The present phylogeographic study screened the COI segment using the sequencing technique to study M. rosenbergii populations collected from eight locations in Malaysia in the peninsular and east of Malaysia. These populations exhibited high genetic differentiation (FST: 0.62503) mainly due to the sample from Sabah. However, the adjacent population (Sarawak) was similar to that in Peninsular Malaysia, even though Northern Sarawak showed sub-population differentiation from the main cluster (cluster I) indicating that the genetic diversity of Northern Sarawak was more restricted. Beside, cluster II observed in the study indicated and confirmed the recent aquaculture activities of restocking the Kedah, Perak and Sarawak populations. Knowledge of the levels of genetic differentiation in N. norvegicus and M. rosenbergii could assist in the management of the species. N. norvegicus could be managed as one stock and conservation and recovery programme could be carried out based on the knowledge that all studied populations exhibited lack genetic differentiation within and between populations. In contrast, M. rosenbergii that possessed high level of genetic differentiation have to be managed separately, especially for a unique population such as the one in Sabah. The outcomes of this study could also be useful for future research in the conservation of wild population, as well as aquaculture management and product improvement purposes. The finding of Sabah as a unique population could potentially be useful for aquaculture improvement programmes. One of the most important aspects is to see whether Sabah population possessed high resistant to the disease infection. A preliminary study was conducted to investigate the susceptibility of a Malaysian wild population of M. rosenbergii to infection by the human food-poisoning bacterium V. parahaemolyticus. Nonetheless, the virulence stage of the bacterial strain, the status of the immune system of the host, the size and age of the experimental animals as well as the dose of injected bacteria might all have contributed to the inconclusiveness of the results. However, the principle of screening wild populations for disease resistance is sound, and may lead to improvements in the quality of the broodstock used in the Malaysian aquaculture industry.
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Kurmaly, Karim. "Studies on the acceptability and digestibility of artificial diets by crustacea." Thesis, Bangor University, 1990. https://research.bangor.ac.uk/portal/en/theses/studies-on-the-acceptability-and-digestibility-of-artificial-diets-by-crustacea(d33a9fc5-c43e-46d4-a9ac-5b430fad8ba6).html.
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This work investigates the factors controlling production and determines the biophysical properties of cross-linked protein coated microencapsulated diets, with a view to enhancing their acceptability and digestibility to omnivorous and carnivorous larvae. To estimate optimal feed larvae of Penaeus monodon on microencapsulated diets, facilitate live transportation and add to the biological knowledge of the species, the relationship between metabolic rate/temperature and energetics of the larval stages were investigated. Also described, are laboratory growth and survival trials with P. monodon larvae fed on cross-linked protein microencapsulated diets. Success with P. monodon larvae, led to investigations on acceptability, growth and energetics of juvenile P. monodon reared on an artificial diet. For comparison, a similar line of approach was adopted with the carnivorous larvae of Homarus gammarus. Studies on the physiological energetics of the larvae were followed by investigations on acceptability, growth and digestibility of artificial diets fed to H. gammarus larvae. The final discussion attempts to correlate the contrasting larval growth/survival results to the different energy strategies adopted by the larvae.
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Esterhuizen, J. A. "Towards the development of a protocol for rearing juvenile rock lobster, Jasus lalandii." Connect to this title online, 2004. http://eprints.ru.ac.za/171/.
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Hosie, Deborah Ann. "Aspects of the physiology of decapod crustaceans with particular reference to the live marketing of Cancer pagurus (L) and Necora puber (L)." Thesis, University of Hull, 1993. http://hydra.hull.ac.uk/resources/hull:3588.
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The crabs Cancer pagurus (L) and Necora puber (L) are exported live, in bulk, from the UK to various continental countries. The success of this relatively new trade is marred by the incidence of mortalities and impaired quality of the delivered product. These studies addressed various causes - procedural and biological - of these events.Descriptions are given of detailed examinations of handling and other marketing protocols for both species from point of capture to arrival at continental dealer's premises. Such examinations were made with the help of a number of major dealers in the UK, Spain and France and included studies of handling, packing, holding and transportation methods, physical damage assessments before and after consignment, and chemical and biochemical analyses of seawater and blood samples.Dissolved ammonia levels were found to increase greatly in the fixed volume water of vivier tanks and this was found to be matched by correspondingly high blood ammonia values of the contained animals. The measurement of both free ammonia and ionic ammonia efflux rates of juvenile and adult Cpagurus and Npuber in media with high dissolved ammonia levels was investigated and was found to be related to concentration gradients between the internal and external media. The fluxes could be explained on the basis of diffusion down concentration gradients. When animals were transferred to media with higher ammonia levels than those in blood, a cessation of efflux, or even a net influx of ammonia (NH4+) occurred.During emersion, blood ammonia concentration rose. Such accumulated ammonia was very rapidly off loaded when the animals were re-immersed.The data produced has been discussed in the context of crustacean physiology and of improving the expectations of delivering a live, quality product after journeys of several days.
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Esterhuizen, J. A. "Towards the development of a protocol for rearing juvenile rock lobster, Jasus lalandii." Thesis, Rhodes University, 2005. http://hdl.handle.net/10962/d1005174.
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The diversification of current aquaculture practise in South Africa is crucial for the future development of the industry. The rock lobster, Jasus lalandii has been identified as a possible candidate species for shore based culture in systems similar to those used for abalone farming. Reduced Total Allowable Catch (TAC's) and an increased minimum legal size were implemented as management strategies to relieve fishing pressure on natural stocks of J. lalandii, and in turn led to increased market demand and a possible niche for farmed lobsters. High puerulus settlement along the Namibian coast, together with other favourable aquaculture attributes, indicate that the commercial grow out of wild harvested juveniles could be feasible. The aim of study was to investigate the feasibility of growing out rock lobsters in shore based systems in Namibia and South Africa. The experimental objectives of the project were to investigate the nutritional requirements, as well as the effect of stocking density and tank design on growth and survival of J. lalandii. The economic viability of shore based rock lobster farming was then evaluated based on the experimental results and typical capital requirements of an abalone farm in South Africa. Puerulus and early juvenile rock lobsters were collected in Luderitz, Namibia and transported to HIK Abalone Farm in Hermanus, South Africa where they were acclimated in black fibre glass tanks in a flow through system. The pueruli were stocked at 50, 75, 100 and 125/m² and early juveniles at 20, 30, 40 and 50/m² to test the effect of density on growth and survival. A comparative dietary study with both size classes was conducted using a mussel diet (Choromytilus meridionalis and Mytilus galloprovincialis), a commercial shrimp feed diet and a rotational diet comprising both mussels and shrimp feed. Tanks provided with "v-shaped" asbestos hides, PVC hides and no hides were compared to test the effect on growth rate and survival of pueruli. All treatments were conducted in triplicate. Temperatures were recorded twice daily while water quality parameters were tested every second week. The results indicate that density had a significant effect on growth and survival on post-pueruli. An initial stocking density of 75 post-pueruli/m² is regarded as optimal both in terms of the growth rate and biomass production per tank. No differences in growth and survival rates were attained in the early juvenile size class. This indicates that higher densities can be used to rear juvenile J. lalandii. No significant differences were obtained in growth rate when reared under different hide conditions although asbestos hides yielded significantly higher survival rates (93.3 %) compared to the tanks provided with PVC hides (74.04 %) and no hides (77.8 %, p≤0.05). As a result of the high survival rate observed in tanks provided with "V-shaped" asbestos hides, these tanks also yielded higher biomass production per tank (297.8 grams) compared to the tanks provided with PVC hides and no hides (261.09 and 260.5 grams respectively). In the diet trials, growth rates of post pueruli and juvenile lobsters fed the mussel and rotational (mussel and shrimp feed) diets did not differ significantly, however, growth rates of lobsters fed the shrimp feed only diet was significantly lower than both the mussel and rotational diets (p≤0.05). Lobsters fed the mussel diet yielded significantly higher survival rates compared to lobsters fed either the rotational diet or shrimp feed diet only. An imbalance in the fatty acid profile of the shrimp feed could have been a major contributing factor to the poor growth and survival in lobsters fed the shrimp feed only diet as the level of linoleic acid (LOA) was exceptionally high resulting in a high (n -6):(n-3) ratio (1.01) compared to the mussel and rotational diets (0.17 and 0.56 respectively). The low level of arachidonic acid (ARA) in the shrimp feed diet could be a further contributing factor explaning for the poor growth and survival of juvenile rock lobsters. An economic feasibility study was conducted at the end of the experimental phase by modelling a hypothetical shore based rock lobster farm. A projection of production costs and revenues was based on the typical costs of a shore based abalone farm and the current market prices for wild harvested J. lalandii. The economic viability was evaluated using benefit-cost ratios, payback period, internal rate of return and breakeven analysis. Sensitivity analyses revealed that the projected lobster growth and survival rates were the main biological factors influencing the economic feasibility of the hypothetical rock lobster farm. An assumed four year grow out period at a low stocking density yielded more lucrative internal rate of return (IRR), benefit-cost ratio, payback period and net present values (NPV) than a five year grow out period at a high density. The four year grow out scenario proved to be more robust to the fluctuating Rand/US$ exchange rate and could accommodate a lower lobster survival rate. Results presented in this study indicate that rock lobster farming is a marginal commercial prospect based on current production performance and costs. Further research to develop effective puerulus collection techniques as well as to make lobster grow out technology more cost effective is required.
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Combes, Jason Charles Hadley. "Aspects of the biology and fisheries ecology of the velvet swimming crab, Necora puber (L.), and the squat lobsters Munida rugosa (Fabricius) and M.sarsi Huss (Crustacea: Decapoda) in Scottish waters." Thesis, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248416.
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Overton, Julia Lynne. "Morphometric, genetic and reproductive characteristics of mud crabs (genus Scylla de Haan, 1833) from Southeast Asia." Thesis, University of Stirling, 2000. http://hdl.handle.net/1893/2599.
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The edible mud crab, genus Scylla, is important to fisheries and aquaculture throughout the Indo Pacific region, but its taxonomic status has been confused for decades and a new classification has only recently been proposed. This project was undertaken to investigate the species status of mud crabs in Southeast Asia, with a view to deciding whether two sympatric morphs of Scylla found in Ban Don Bay, Surat Thani Province, Thailand, are two separate species. A further aim was to elucidate any possible pre-zygotic reproductive isolating mechanisms (RIMs) and ecological features that maintain the apparent sympatry between these two morphs. Mud crabs were collected from a primary site (Surat Thani, Thailand) as well as from six other locations in Thailand, Vietnam, Malaysia and Bangladesh. Crab samples from the latter sites were used selectively to provide a comparison to the primary study site. Descriptive taxonomy, multivariate morphometrics and allozyme electrophoresis were used to a) determine the number of species present within the crab samples collected; b) to ascertain which species they represent; c) to discover any geographical variation between locations sampled; d) to produce a possible phylogeny that summaries the relationship between Scylla species; and e) to look for pre-zygotic RIMs to explain the sympatry of the two morphs in Surat Thani. Findings from the present study reinforce the recent revision of the taxonomy of the genus Scylla into four species, S. serrata, S. olivacea, S. tranquebarica and S. paramamosain and provides new information on two of the four species which are dominant within Southeast Asia, including Ban Don Bay, Surat Thani Province, S. paramamosain and S. olivacea. Population studies showed both genetic and morphological differentiation between conspecific populations of S. paramamosain and S. olivacea, indicating stock structure for each species, although there is some disparity between morphological and genetic distances for S. paramamosain. This is discussed in relation to the effects of larval dispersal mechanisms and the subsequent recruitment of juvenile crabs. Phylogenetic interpretation of both genetic and morphological characters revealed that both S. serrata and S. olivacea are the most diverged of the four Scylla species; however, the direction of evolution is open to interpretation and the evidence for either S. olivacea or S. serrata as the more primitive species are discussed. Reproductive studies on the two mud crab species found in Surat Thani revealed no physical barrier to hybridization. Both species have a protracted breeding season which continues throughout the year. However, the size at first sexual maturity was significantly smaller for S. olivacea when compared to S. paramamosain. This and other potential mechanisms that may maintain these two species sympatrically are discussed. The clarification of four Scylla species, and the establishment of diagnostic genetic and morphological characters that can be used to identify them, means that research can now focus on both the ecology and life history of these closely related species. Such information is needed urgently with respect to fisheries management as well as to understanding the environmental requirements of each species in order to develop their potential for aquaculture.
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Amaral, Antonio Lucas Sforcin. "Siriboia ou tamburutaca (Crustacea Stomatopoda): morfologia das garras raptoriais e sua relação com acidentes em humanos /." Botucatu, 2020. http://hdl.handle.net/11449/192211.
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Orientador: Antonio Leão CastilhoResumo: Os siriboias são crustáceos pertencentes à ordem Stomatopoda e conhecidos pelo segundo toracópode modificado em garra raptorial, capaz de golpear e quebrar conchas de moluscos, e capturar suas presas. Podem ser separados em dois grupos de acordo com a morfologia das garras: o grupo esmagador, que desfere golpes em sua presa similares a socos de alta potência, e o outro grupo, perfurador, que perfura a presa com as projeções pontiagudas localizadas no dáctilo, último segmento da garra. Existem frequentes relatos anedóticos sobre acidentes em humanos causados por esses crustáceos, mas as informações são imprecisas e muitas vezes o animal não é corretamente identificado pelas vítimas. Este estudo apresenta o relato de 23 pescadores de Ubatuba - São Paulo, que afirmam considerar o siriboia perigoso e que evitam contato direto por conhecerem o risco que o animal oferece, e que os acidentes costumam acontecer com pessoas pouco familiarizadas com o crustáceo. Inclui um relato de lesão causada pelo urópode, informação não documentada anteriormente, e quatro relatos documentados de lesões causadas pelas garras em seres humanos. O estudo resultou ainda em um material informativo sobre os siriboias e prevenção dos acidentes.
Abstract: Siriboias are crustaceans belonging to the order Stomatopoda that are known for the second thoracopods modified to raptorial claws, capable of striking and breaking shells of molluscs and capturing their prey. They can be classified in two groups according to the morphology of the claws: the smasher group, which strikes its prey similar to high-powered punches, and the spearer, which pierces the prey with pointed projections located in the dactyl, last segment of the claw. There are frequent anedoctal reports of human injuries caused by these crustaceans, but the information is inaccurate and often the animal is not correctly identified by the victims. This study presents tertimony of 23 fishermen from Ubatuba - São Paulo, which claim to consider the siriboia as dangerous animals and avoid direct contact, due to know the risk offered. The injuries usually happen in people unfamiliar with the crustacean. It includes one report of an injury caused by the uropod, previously undocumented information, and four documented reports of human injuries caused by the claws. The study proposes informative material about the siriboias and the prevention of injuries.
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Crowley, Claire Elizabeth. "Aging of Florida Blue Crabs, Callinectes sapidus, Through the Biochemical Extraction of Lipofuscin." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4022.
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The blue crab, Callinectes sapidus, represents an ecologically and economically important component of marine and estuarine ecosystems. In Florida, blue crab landings accounted for $9.6 million dollars during the 2010 fishing season. Accurate stock assessments for this valuable fishery are essential. Age is a critical biological component of accurate stock assessments; however, blue crabs and other crustaceans are especially difficult to age because of the complex nature of discrete growth. Biochemical extraction of an aging pigment, lipofuscin, was developed using blue crab eyestalks. The current study investigated the effects of freezing preservation on lipofuscin extracts and examined whether the extraction methodology, developed by Chesapeake Bay researchers, was useful for aging Tampa Bay blue crabs populations. Significant differences in lipofuscin index were found between samples frozen (2 weeks at -80°C) prior to analysis and those processed and assayed immediately (p < 0.001). Quarterly assays of the cohort of known-age individuals revealed a negative linear trend (y = -0.12x + 0.49, p < 0.001) in lipofuscin index over a 12-month period. This result suggests that extraction of lipofuscin is not appropriate for age determination of Florida blue crabs. Investigations into possible causes of the negative trend in lipofuscin suggest this method deserves further examination and refinement before it is acceptable as a reliable method for age determination in Florida blue crabs. Growth data of the known-age population collected during this study revealed that blue crabs in Tampa Bay can reach exploitable size in under sixth months and female crabs can reach sexual maturity within seven months of hatching. These growth patterns have the potential to enhance future Florida stock assessments.
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Bernardo, Camila Hipolito. "Dinâmica populacional do camarão “barba-ruça” Artemesia longinaris Spence Bate, 1888 (Crustacea, Decapoda, Penaeidae) em dois períodos distintos (intervalo de 20 anos) no litoral sudeste do Brasil." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/152239.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Artemesia longinaris Spence Bate, 1888 é considerada uma espécie monotípica endêmica das zonas costeiras do Atlântico Sul Ocidental. Vem sendo recentemente explorada comercialmente devido à queda nos estoques dos camarões de maior interesse comercial. Esse estudo visou comparar a distribuição espaço temporal da A. longinaris em um intervalo de 20 anos (novembro/1988 a outubro/ 1989 e novembro/2008 a outubro/2009) na Enseada da Fortaleza, em Ubatuba, São Paulo. Em ambos os períodos os indivíduos e fatores ambientais (temperatura e salinidade da água de fundo e superfície, sedimento) foram coletados em 7 transectos. Uma RDA foi feita para relacionar os fatores ambientais com a abundância dos indivíduos. O teste de Mann-Whitney foi realizado para comparar fatores ambientais e abundância dos indivíduos entre os dois períodos. Foram coletados de 3088 espécimes no primeiro período e 1252 no segundo, não havendo diferença significativa entre os períodos (p>0,05). Apesar de não apontada estatisticamente houve uma redução do número de indivíduos entre os períodos. Segundo resultados da RDA, uma forte correlação negativa entre a abundância e a classe C (silte+argila) do sedimento, mostrou que o aumento desse tipo de sedimento no segundo período, pode ter contribuído para a redução do número de indivíduos. Aliado a isso, houve menores reflexos da massa ACAS nesta enseada, ocasionando uma redução do número de indivíduos. Esta massa de água reduz as temperaturas de fundo, sendo que a espécie em estudo possui uma história evolutiva vinculada a águas oceânicas frias. Além das condições do sedimento e reflexos da ACAS, a intensa atividade de pesca de arrasto de camarão na região de Ubatuba pode ter contribuído para a redução do número de indivíduos, pois como já é sabido, a pesca de arrasto é considerada uma atividade predatória e causa desestabilização da comunidade bentônica. Em ambos os períodos a espécie se concentrou nos transectos mais profundos (I, VI e VII) onde as características ambientais eram mais favoráveis (temperatura baixa e salinidade alta). O conhecimento sobre a distribuição ecológica desta espécie é importante para que haja um manejo sustentável dos estoques pesqueiros. A Enseada da Fortaleza é desde 8 de outubro de 2008, uma Área de Proteção Ambiental (APA), que visa a preservação dessa biodiversidade. Estudos futuros poderão mostrar se o estoque do camarão A. longinaris está se recuperando devidos às medidas de proteção estabelecidas na região.
Artemesia longinaris Spence Bate, 1888 is considered a monotypic species endemic to the coastal areas of the Western South Atlantic. It has recently been commercially exploited due to the fall in stocks of shrimps of major commercial interest. This study aimed at comparing the temporal distribution of A. longinaris over a period of 20 years (November / 1988 to October / 1989 and November / 2008 to October / 2009) at Fortaleza Bay in Ubatuba, São Paulo. In both periods the individuals and environmental factors (temperature and salinity of the bottom and surface water, sediment) were collected in 7 transects. An RDA was made to relate environmental factors to the abundance of individuals. The Mann-Whitney test was performed to compare environmental factors and abundance of individuals between the two periods. There were collected 3088 specimens in the first period and 1252 specimens in the second, with no significant difference between the periods (p> 0.05). Although not statistically indicated, there was a reduction in the number of individuals between the periods. According to the results of the GDR, a strong negative correlation between the abundance and class C (silt + clay) of the sediment showed that the increase of this type of sediment in the second period may have contributed to the reduction of the number of individuals. Along with this, there were smaller reflexes of the ACAS mass in this cove, causing a reduction in the number of individuals. This body of water reduces background temperatures, and the species under study has an evolutionary history linked to cold oceanic waters. In addition to the ACAS sediment and reflex conditions, the intense shrimp trawling activity in the Ubatuba region may have contributed to a reduction in the number of individuals, since, as is well known, trawling is considered a predatory activity and causes destabilization of the benthic community. In both periods the species was concentrated in the deeper transects (I, VI and VII) where the environmental characteristics were more favorable (low temperature and high salinity). Knowledge about the ecological distribution of this species is important for sustainable management of fish stocks. The Fortress Cove is since October 8, 2008, an Environmental Protection Area (APA), which aims to preserve this biodiversity. Future studies could show whether the shrimp A. longinaris stock is recovering due to the protection measures established in the region.
2015/13607-6
Books on the topic "Crustacean Fisheries"
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Wickins, J. F. Crustacean farming: Ranching and culture. 2nd ed. Oxford: Blackwell Scientific Publications, 2002.
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Wickins, J. F. Crustacean farming: Ranching and culture. 2nd ed. Oxford: Blackwell Scientific Publications, 2002.
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N, Horst Michael, and Freeman John A. 1948-, eds. The Crustacean integument: Morphology and biochemistry. Boca Raton: CRC Press, 1993.
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JSPS-DGHE International Symposium on Fisheries Science in Tropical Area (7th 2002 Bogor, Indonesia). Proceeding of the JSPS-DGHE International Seminar on Fisheries Science in Tropical Area: Towards the integrated sustainable fisheries in Asia : Crustacean fisheries 2002, biology, technology, and management, Bogor, Indonesia, August 20-21, 2002. [Tokyo]: Japan Society for the Promotion of Science, 2003.
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Williams, Austin B. Lobsters of the world: An illustrated guide : lobsters of the world in U.S. trade. Huntington, N.Y: Osprey Books, 1988.
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J, Provenzano Anthony, ed. Economic aspects, fisheries and culture. Orlando: Academic Press, 1985.
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Patalas, K. Planktonic crustaceans in lakes of Canada (distribution of species, bibliography). Winnipeg, Man: Central and Arctic Region, Dept. of Fisheries and Oceans, 1994.
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Tacon, Albert G. J. Feed ingredients for crustaceans natural foods and processed feedstuffs. Rome: Food and Agriculture Organization of the United Nations, 1993.
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Dawson, Elliot W. King crabs of the world (Crustacea, Lithodidae) and their fisheries: A comprehensive bibliography. Wellington: New Zealand Oceanographic Institute, Division of Water Sciences, DSIR, 1989.
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Salmerón, Luis Angel Pérez. Los animales comestibles de importancia comercial en aguas mexicanas: Peces, moluscos, crustaceos. México: Cía. Editorial Continental, 1985.
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Hansen, M. E., and A. Illanes. "Applications of crustacean wastes in biotechnology." In Fisheries Processing, 174–205. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-5303-8_8.
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Paramo, J., M. Grijalba-Bendeck, D. Pérez, A. Espinoza-Tenorio, and M. Wolff. "Conservation Strategies for Potential New Deep-Sea Crustacean Fisheries in the Colombian Caribbean under an Ecosystem Approach." In Deep-Sea Pycnogonids and Crustaceans of the Americas, 421–41. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-58410-8_18.
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Wilhelmsson, Dan, and Olivia Langhamer. "The Influence of Fisheries Exclusion and Addition of Hard Substrata on Fish and Crustaceans." In Marine Renewable Energy Technology and Environmental Interactions, 49–60. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-8002-5_5.
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Gardner, Caleb, Reginald A. Watson, Anes Dwi Jayanti, Suadi, Mohsen AlHusaini, and Gordon H. Kruse. "Crustaceans as Fisheries Resources: General Overview." In Fisheries and Aquaculture, 2–20. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190865627.003.0001.
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Much of the biological and other research efforts on crustaceans have been driven by their importance to humans as a food source. Production comes from a diverse array of methods and scales of extraction, from small recreational or subsistence fisheries to industrial-scale operations. Most crustacean catch comes from shrimp fisheries, with over two million tons taken in 2014, mainly by trawl. The genera Acetes, Fenneropenaeus, and Pandalus account for around three quarters of this catch. Crab, krill, and lobster are the other main crustacean products (around 600,000 t crab, 380,000 t krill, and 300,000 t lobster in 2014). Trends in crustacean fisheries are broadly similar to those of other seafood, although crustaceans often target different market segments and receive higher prices than fish. Crustacean fisheries management faces many challenges with management of bycatch from trawl gears especially significant. Fortunately, crustaceans tend to be easily handled with low discard mortality, and this has enabled widespread use of regulations based on size, maturity, or sex (e.g., male-only fisheries). Total allowable catch (TAC) limits are widely used and highly effective for ensuring sustainable harvests when set responsibly using good information. TAC systems are often combined with catch share or individual transferable quota systems, which had a mixed history in crustaceans, sometimes reducing overall community benefit. This parallels the challenge facing fisheries globally of ensuring that harvests are not only sustainable but also deliver benefits to the wider community beyond the commercial fishers; management of some crustacean fisheries is at the forefront of these developments.
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Penn, J. W., N. Caputi, and R. Melville-Smith. "Crustacean Fisheries." In Encyclopedia of Ocean Sciences, 570–78. Elsevier, 2001. http://dx.doi.org/10.1006/rwos.2001.0453.
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Penn, James W., Nick Caputi, Simon de Lestang, Danielle Johnston, Mervi Kangas, and Justin Bopp. "Crustacean Fisheries." In Encyclopedia of Ocean Sciences, 324–37. Elsevier, 2019. http://dx.doi.org/10.1016/b978-0-12-409548-9.09577-4.
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Penn, J. W., N. Caputi, and R. Melville-Smith. "Crustacean Fisheries." In Encyclopedia of Ocean Sciences, 699–707. Elsevier, 2001. http://dx.doi.org/10.1016/b978-012374473-9.00453-7.
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Nowak, Barbara F., Melissa B. Martin, and Sebastián Boltaña. "Parasitic Crustaceans." In Fisheries and Aquaculture, 401–34. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190865627.003.0016.
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This chapter provides a brief overview of crustacean parasites that infect commercially important fish and shellfish. Crustaceans are a diverse group of arthropods, with over 60,000 species that are significant to the aquaculture and fisheries sector, including parasitic species affecting other crustaceans, mollusks, and fishes. This chapter focuses on parasitic caligid copepods (sea lice), cymothoid isopods, and pea crabs of high economic impacts on commercially important aquatic species. The biology of the parasites, their effects on their hosts, the epidemiology of the infections, and economic impacts of these groups are described. Chemical treatments and husbandry modifications as management options for a range of crustacean parasites are presented, which includes the use of cleaner fish to remove parasites, specially designed cages to reduce infestation of parasites, or moving farms to deeper waters. The utilization of crustacean parasites as marine pest controls is further discussed, with emphasis on either its potential benefits or the negative effects on native crab populations. Despite the continuous adverse impacts parasitic crustaceans have on aquaculture, the progressive understanding of their biology and ecology may eventually lead to mitigation, if not complete eradication, of the parasites.
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Navarro-Barranco, Carlos, Macarena Ros, José M. Tierno de Figueroa, and José M. Guerra-García. "Marine Crustaceans as Bioindicators: Amphipods as Case Study." In Fisheries and Aquaculture, 436–62. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190865627.003.0017.
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A bioindicator species can be defined as “an organism that provides information on the environmental conditions of its habitat by its presence or absence, and its behavior.” In this sense, crustaceans present many biological and ecological characteristics that make them particularly useful as bioindicators (e.g., widespread distribution in different habitats and geographical areas, key role in community functioning, great diversity of life history strategies). Within Crustacea, the order Amphipoda has been considered an especially relevant and suitable group due to its direct development and its special sensibility to disturbances, among other reasons. Crustaceans can be used in biomonitoring studies in a wide variety of habitats (e.g., both soft- and hard-bottom substrata from intertidal to deep environments) and for different types of environmental stressors. An extensive amount of literature has reported the sensitivity of crustacean species to heavy metal contamination, sewage and desalination discharges, or engineering and aquaculture activities, among others. Special emphasis has been placed on the role of crustaceans in the most used indexes (e.g., AMBI, BENTIX, BOPA) developed to establish the environmental quality of European coastal and marine areas. Crustaceans are one of the groups with a higher contribution to those indexes, although their presence is not necessarily indicative of low environmental disturbances. Within amphipods, the importance of the family Caprellidae as a monitoring tool in environmental programs (e.g., trace metal or tributyltin pollution) is highlighted. Alien crustaceans can also play a pivotal role as bioindicators of anthropogenic pressures, and their likely influence on the accuracy of ecological assessment programs should be taken into account. Finally, there is an increasing need to improve our scarce taxonomic knowledge in many crustacean groups since that information is vital for the correct development of monitoring tools. Studies dealing with the species’ ecological and biological traits are also encouraged in order to understand the potential application of these species as bioindicators.
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Abadilla, Miles, W. Ray McClain, Taku Sato, Luis M. Mejía-Ortíz, and Miguel A. Penna-Díaz. "Inland Crustacean Fisheries." In Fisheries and Aquaculture, 182–206. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190865627.003.0008.
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Freshwater crustacean inland fisheries are typically confined to small local areas that are associated with bodies of water, like rivers and swamps. They are small-scale fisheries, enough to supply the requirements for local commercial use, and considered mainly as a subsistence resource for small fishing communities. As such, inland crustacean fisheries exemplify a subsistence opportunity for small countries with limited economic power, particularly rural communities. Crustaceans are a relevant protein source alternative to fish, and they are often also associated with local gastronomical and cultural identity. Data for the most commonly caught species are often unavailable since these fisheries exist in remote areas where government or institutional monitoring is limited, making it difficult to obtain reliable data about small-scale fisheries. Nonetheless, the captured species and the techniques used are widely diverse. In inland fisheries, the main target species are prawns from the genus Macrobrachium, gathered within the tropics all over the world. Natural fisheries of crayfishes in their native range exist on several continents, with Procambarus clarkii, Pacifastacus leniusculus, and Astacus astacus as the main commercial species. Some of them have also become a fisheries resource in areas where they were introduced. The only terrestrial crab fishery is for an anomuran, the coconut crab Birgus latro. The future of most of these fisheries depends in part on the health of the water sources threatened by contamination and unrestricted waterways jeopardized by the construction of dam-like structures that block the migration of some species to complete their reproductive cycles. The creation of regulatory policies is key for keeping the fishery activity self-sustainable because most of the exploitation depends on wild populations. There are some conservation efforts implemented thanks to the relevant gastronomical value of the species, as well as to economically sustain local communities in remote areas.
Conference papers on the topic "Crustacean Fisheries"
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Zaklan, S. D. "Review of the family Lithodidae (Crustacea: Anomura: Paguroidea): Distribution, biology, and fisheries." In Crabs in Cold Water Regions: Biology, Management, and Economics. Alaska Sea Grant, University of Alaska Fairbanks, 2002. http://dx.doi.org/10.4027/ccwrbme.2002.53.
Full textReports on the topic "Crustacean Fisheries"
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Börjesson, Patrik, Maria Eggertsen, Lachlan Fetterplace, Ann-Britt Florin, Ronny Fredriksson, Susanna Fredriksson, Patrik Kraufvelin, et al. Long-term effects of no-take zones in Swedish waters. Edited by Ulf Bergström, Charlotte Berkström, and Mattias Sköld. Department of Aquatic Resources, Swedish University of Agricultural Sciences, 2023. http://dx.doi.org/10.54612/a.10da2mgf51.
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Marine protected areas (MPAs) are increasingly established worldwide to protect and restore degraded ecosystems. However, the level of protection varies among MPAs and has been found to affect the outcome of the closure. In no-take zones (NTZs), no fishing or extraction of marine organisms is allowed. The EU Commission recently committed to protect 30% of European waters by 2030 through the updated Biodiversity Strategy. Importantly, one third of these 30% should be of strict protection. Exactly what is meant by strict protection is not entirely clear, but fishing would likely have to be fully or largely prohibited in these areas. This new target for strictly protected areas highlights the need to evaluate the ecological effects of NTZs, particularly in regions like northern Europe where such evaluations are scarce. The Swedish NTZs made up approximately two thirds of the total areal extent of NTZs in Europe a decade ago. Given that these areas have been closed for at least 10 years and can provide insights into long-term effects of NTZs on fish and ecosystems, they are of broad interest in light of the new 10% strict protection by 2030 commitment by EU member states. In total, eight NTZs in Swedish coastal and offshore waters were evaluated in the current report, with respect to primarily the responses of focal species for the conservation measure, but in some of the areas also ecosystem responses. Five of the NTZs were established in 2009-2011, as part of a government commission, while the other three had been established earlier. The results of the evaluations are presented in a synthesis and also in separate, more detailed chapters for each of the eight NTZs. Overall, the results suggest that NTZs can increase abundances and biomasses of fish and decapod crustaceans, given that the closed areas are strategically placed and of an appropriate size in relation to the life cycle of the focal species. A meta-regression of the effects on focal species of the NTZs showed that CPUE was on average 2.6 times higher after three years of protection, and 3.8 times higher than in the fished reference areas after six years of protection. The proportion of old and large individuals increased in most NTZs, and thereby also the reproductive potential of populations. The increase in abundance of large predatory fish also likely contributed to restoring ecosystem functions, such as top-down control. These effects appeared after a 5-year period and in many cases remained and continued to increase in the longer term (>10 years). In the two areas where cod was the focal species of the NTZs, positive responses were weak, likely as an effect of long-term past, and in the Kattegat still present, recruitment overfishing. In the Baltic Sea, predation by grey seal and cormorant was in some cases so high that it likely counteracted the positive effects of removing fisheries and led to stock declines in the NTZs. In most cases, the introduction of the NTZs has likely decreased the total fishing effort rather than displacing it to adjacent areas. In the Kattegat NTZ, however, the purpose was explicitly to displace an unselective coastal mixed bottom-trawl fishery targeting Norway lobster and flatfish to areas where the bycatches of mature cod were smaller. In two areas that were reopened to fishing after 5 years, the positive effects of the NTZs on fish stocks eroded quickly to pre-closure levels despite that the areas remained closed during the spawning period, highlighting that permanent closures may be necessary to maintain positive effects. We conclude from the Swedish case studies that NTZs may well function as a complement to other fisheries management measures, such as catch, effort and gear regulations. The experiences from the current evaluation show that NTZs can be an important tool for fisheries management especially for local coastal fish populations and areas with mixed fisheries, as well as in cases where there is a need to counteract adverse ecosystem effects of fishing. NTZs are also needed as reference for marine environmental management, and for understanding the effects of fishing on fish populations and other ecosystem components in relation to other pressures. MPAs where the protection of both fish and their habitats is combined may be an important instrument for ecosystembased management, where the recovery of large predatory fish may lead to a restoration of important ecosystem functions and contribute to improving decayed habitats. With the new Biodiversity Strategy, EUs level of ambition for marine conservation increases significantly, with the goal of 30% of coastal and marine waters protected by 2030, and, importantly, one third of these areas being strictly protected. From a conservation perspective, rare, sensitive and/or charismatic species or habitats are often in focus when designating MPAs, and displacement of fisheries is then considered an unwanted side effect. However, if the establishment of strictly protected areas also aims to rebuild fish stocks, these MPAs should be placed in heavily fished areas and designed to protect depleted populations by accounting for their home ranges to generate positive outcomes. Thus, extensive displacement of fisheries is required to reach benefits for depleted populations, and need to be accounted for e.g. by specific regulations outside the strictly protected areas. These new extensive EU goals for MPA establishment pose a challenge for management, but at the same time offer an opportunity to bridge the current gap between conservation and fisheries management.