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1.
渔业资源评估一般有两种数据来源,即科学调查数据和渔业生产数据;前者需要定期出海采样,耗时长且费用高,后者易于获取但样本代表性存在问题。本研究以山东近海口虾蛄为例,基于电子体长频率方法(ELEFAN)评估了口虾蛄的生长参数,采用bootstrap 重抽样方法比较了基于渔业生产数据与科学调查数据分析结果的差异,旨在探讨渔业生产数据在估算生长参数上的准确性。结果表明,科学调查数据估算得到的口虾蛄von Bertalanffy季节性生长方程中的极限体长L∞=193.16 mm, K=0.62,生产数据估算得到的口虾蛄极限体长L∞=171.70 mm,K=0.67;非参数检验表明基于两种采样方法所求得的口虾蛄的极限体长L∞呈现显著性差异, K 和“夏季点”ts 均呈现不显著性差异。本研究表明,渔业生产数据在一定程度上能够反映生物的生长状况,对K 和ts 的估算与科学调查数据估算的结果较为接近,但对极限体长的估算误差较大。因此口虾蛄生长研究需要依靠科学调查数据的支持,同时渔业生产数据可以作为辅助信息。  相似文献   

2.
Georges Bank haddock is a recently recovered fish stock in the New England groundfish fishery. Due to federal constraints under the Magnuson–Steven Act, however, this stock cannot be optimally exploited due to the bycatch of other critical species in the New England groundfishery such as cod and yellowtail flounder which are overfished. The Ruhle trawl and Separator trawl are examples of recent advances in gear technology that have been shown to significantly increase haddock to bycatch ratios. This study models the groundfish fishery through a mixed-stock yield model which incorporates technological interactions. We also develop a socio-economic model that quantifies the amount of employment and producer surplus associated with three trawl types. Our results explore policy situations regarding the use of the new trawls. By bridging the biological and socio-economic models, we are able to view the fishery as a system that more accurately represents stakeholder views. Our model shows that each trawl, when used exclusively, produces different optimum strategies and therefore an optimum management strategy would most likely include a combination of trawl types. Our results also support the logic of using modified trawls for haddock fishing trips in which bycatch is strictly regulated (“B days”) as the Ruhle trawl is able to maintain 80% of catches caught by a conventional trawl while reducing bycatch up to over 60%. This paper is a first step towards an aid for policy makers to examine fishery gear trade-offs and the resulting biological and socio-economic consequences of different management actions within the constraints of the Magnuson–Stevens Act.  相似文献   

3.
黄河口鱼类底拖网调查采样断面数的优化   总被引：4，自引：2，他引：2  
优化调查采样设计方案,利用有限的调查成本获取准确可靠的渔业资源数据,对于开展独立于渔业的科学调查十分重要。根据2013年8、10月和2014年2、5月在黄河口及其邻近水域进行的渔业资源底拖网调查数据,选取短吻红舌鳎(Cynoglossus joyneri)和矛尾虾虎鱼(Chaeturichthys stigmatias)作为目标鱼种,以其平均个体体长、平均个体体重为调查采样优化目标,利用计算机模拟方法对黄河口水域的渔业资源底拖网调查生物学数据进行再抽样,以平均体长、平均体重估计值的相对估计误差(REE)、相对偏差(RB)和变异系数(CV)作为优化评价指标,对基于整群抽样方法的黄河口及邻近海域的调查采样断面数进行优化。结果表明,对于目标鱼种的平均体长、平均体重指标,模拟估计值的REE、RB和CV均随着断面数的减少不断增加,调查断面数少于3时,各指标的变化幅度较大。断面数由5减少至3,REE值平均增加2%,RB值平均增加0.13%,CV值平均增加1.95%,同时渔获量降低近40%。因此,断面数为3可视为黄河口及邻近海域可接受的最优调查断面数。  相似文献   

4.
Six species of line-caught coral reef fish (Plectropomus spp., Lethrinus miniatus, Lethrinus laticaudis, Lutjanus sebae, Lutjanus malabaricus and Lutjanus erythropterus) were tagged by members of the Australian National Sportsfishing Association (ANSA) in Queensland between 1986 and 2003. Of the 14,757 fish tagged, 1607 were recaptured and we analysed these data to describe movement and determine factors likely to impact release survival. All species were classified as residents since over 80% of recaptures for each species occurred within 1 km of the release site. Few individuals (range 0.8–5%) were recaptured more than 20 km from their release point. L. sebae had a higher recapture rate (19.9%) than the other species studied (range 2.1–11.7%). Venting swimbladder gases, regardless of whether or not fish appeared to be suffering from barotrauma, significantly enhanced (P < 0.05) the survival of L. sebae and L. malabaricus but had no significant effect (P > 0.05) on L. erythropterus. The condition of fish on release, subjectively assessed by anglers, was only a significant effect on recapture rate for L. sebae where fish in “fair” condition had less than half the recapture rate of those assessed as in “excellent” or “good” condition. The recapture rate of L. sebae and L. laticaudis was significantly (P < 0.05) affected by depth with recapture rate declining in depths exceeding 30 m. Overall, the results showed that depth of capture, release condition and treatment for barotrauma influenced recapture rate for some species but these effects were not consistent across all species studied. Recommendations were made to the ANSA tagging clubs to record additional information such as injury, hooking location and hook type to enable a more comprehensive future assessment of the factors influencing release survival.  相似文献   

5.
The European conger eel, Conger conger, is a fish widely distributed in the north-eastern Atlantic, being an important commercial and recreational fish species. A total of 85 juvenile congers eels were used in this study. Seventy-three congers were captured mainly by hook and pots in inshore waters (10–15 m depth) of the Iberian Peninsula (North Portugal and Vigo), monthly from March 1998 to March 2000. Another twelve specimens have been captured during a research cruise (R.V. “Capricórnio”) in summer 1999 by trawl at depths about 400 m in south Portugal. The length and weight of the congers eels ranged from 38 to 173 cm and 125 to 14,553 g, respectively. The observation of burnt otoliths under UV light proved to be a useful method for ageing conger eels. Marginal increment analysis was used to validate the annual pattern in the deposition of bright zones in the otoliths. Age for the congers ranged from 2 to 12 years. The VBF population growth curve estimates from the otoliths of the females gave results of L∞ = 265 cm, k = 0.07 and t0 = −1.20. Sex determination and gonadal development were obtained from histological analysis. All the specimens collected in the coastal shallow waters were females, either immature or in a developing stage. The ovaries contained oocytes in two main stages of development: a pre-vitellogenic stage and an early vitellogenic stage. The few males (n = 4) observed have been captured in the trawl fishery at deeper waters. The males possessed small cells spermatogonias and spermatocytes clustered in crypts in the testis scattered in a matrix of adipose tissue. The sexual steroids, 17β-oestradiol and testosterone, were measured in blood plasma samples by solid-phase radioimmunoassay. Both sexual steroids presented a high correlation with the sexual development stage in terms of maximum oocyte diameter and gonadosomatic index. This work presents for the first time, data on age, reproductive biology and endocrinology of conger eels captured in the west coast of the Iberian Peninsula.  相似文献   

6.
为查明采样强度对多种类渔业调查中资源量指数估计的影响,实验根据2013年8月、10月和2014年2月、5月黄河口渔业资源底拖网调查数据,选取短吻红舌鳎、方氏云鳚、矛尾虾虎鱼、枪乌贼、口虾蛄、日本蟳和小型鳀鲱鱼类为调查目标,利用计算机模拟方法,以相对估计误差(REE)、相对偏差(RB)、变异系数(CV)和准确度变化率(ACR)等为评价指标,研究了调查样本量对不同种类资源量指数估计的影响。结果显示,各种类资源量指数估计的REE、CV和ACR随断面数增加均逐渐降低并趋于稳定;除在断面数3减到1时,日本蟳、口虾蛄和方氏云鳚等个别种类RB绝对值增大外,其他RB不存在一致性的增大或减小趋势。研究表明,由于不同种类的分布存在时空差异,不同种类需要的调查断面数不同;当目标种类数量空间分布变异较小时,减少调查断面数对采样精确度影响较小,反之则需要更多调查断面数。对于多种类渔业资源调查,需要综合权衡各目标种类来确定最适调查断面数。  相似文献   

7.
This work describes the ontogeny of the digestive tract in thick lipped grey mullet (Chelon labrosus) larvae reared until day 36 post-hatching with the semi-extensive technology in mesocosms. Diet was constituted by live preys, rotifers, Artemia and wild zooplankton, then compound diet was added from day 20 (p. h.). Linear growth, weight growth and digestive enzymes specific activities were studied during larval ontogeny. Pancreatic enzymes (trypsin and amylase) and intestinal enzymes (leucine-alanine peptidase “Leu-ala”, aminopeptidase N “AN” and alkaline phosphatase “AP”) were assayed in larvae sampled throughout the rearing trial to evaluate gastrointestinal maturation along the development.The trypsin specific activities were very high during the first two weeks and then declined as observed in marine fish species. A following increase in trypsin specific activity from day 20 was attributed notably to ingestion of particle compound diet. In contrast to the pattern generally described in fish larvae, amylase specific activity showed a continuous increase. This could be attributed to the fact that C. labrosus is an omnivorous species and suggests that the fish might be able to use efficiently diets containing higher levels of starch or other carbohydrates since the end of larval development.Relative expression of intestinal brush border membrane enzymes (AP and AN) and cytosolic enzyme (Leu-ala), showed an abrupt increase of both AP/leu-ala and AN/leu-ala ratios at day 8 (p. h.), indicating that maturation of intestinal tract in C. labrosus larvae is particularly precocious. It is assumed that larvae of C. labrosus might support early co-feeding and weaning strategies, which could reasonably be initiated since mouth opening.  相似文献   

8.
Series of trials in which mackerel (Scomber scombrus L.) were confined in keepnets at different stocking densities are described. From simple confinement trials it was found that 50% of the fish died after 48 h at a stocking density of 30 fish m−3, equivalent to 6.5 kg m−3. Trials in which fish were held at stocking densities, and for a duration, comparable to those experienced in a “dried up” purse seine prior to “slipping”, showed that up to 90% of “slipped” fish died within 48 h of release. The primary cause of death was probably physical damage, particularly skin loss, caused by abrasion, although there is some evidence that mackerel have a healing process which can accommodate minor skin abrasions. A tagging trial showed a small but significant increase in mortality due to the tagging procedure.  相似文献   

9.
Many marine species are shifting their distributions in response to changing ocean conditions, posing significant challenges and risks for fisheries management. Species distribution models (SDMs) are used to project future species distributions in the face of a changing climate. Information to fit SDMs generally comes from two main sources: fishery-independent (scientific surveys) and fishery-dependent (commercial catch) data. A concern with fishery-dependent data is that fishing locations are not independent of the underlying species abundance, potentially biasing predictions of species distributions. However, resources for fishery-independent surveys are increasingly limited; therefore, it is critical we understand the strengths and limitations of SDMs developed from fishery-dependent data. We used a simulation approach to evaluate the potential for fishery-dependent data to inform SDMs and abundance estimates and quantify the bias resulting from different fishery-dependent sampling scenarios in the California Current System (CCS). We then evaluated the ability of the SDMs to project changes in the spatial distribution of species over time and compare the time scale over which model performance degrades between the different sampling scenarios and as a function of climate bias and novelty. Our results show that data generated from fishery-dependent sampling can still result in SDMs with high predictive skill several decades into the future, given specific forms of preferential sampling which result in low climate bias and novelty. Therefore, fishery-dependent data may be able to supplement information from surveys that are reduced or eliminated for budgetary reasons to project species distributions into the future.  相似文献   

10.
The identification of North Atlantic redfish has been controversial and remains a difficult task due to overlapping of meristic and morphological characters. Here we used nine microsatellite loci to assess the level of genetic differentiation among these species and assess the resolution power of these microsatellite loci for individual assignment-based analyses. Conventional analyses as well as individual Bayesian assignment methods clearly separated the four species of North Atlantic redfish as well as the giant form of Sebastes marinus and the so-called “oceanic” and “deep-sea” types of Sebastes mentella. Locus-by-locus analyses revealed that only five microsatellite loci out of nine used could discriminate the concerned species. The advantage of the Bayesian methods relies in the individual information retrieved. It therefore gave additional information on the interrelationship among species. Indeed, we provide evidence of potential hybridization among species as well as individual misclassification based on morphological identification. We provide a powerful tool to discriminate North Atlantic redfish species, which might be useful for legal issues such as poaching, unintentional harvesting and control label.  相似文献   

11.
  1. One-third of all elasmobranch species currently known to occur in Papua New Guinea are taken as bycatch in the Gulf of Papua trawl fishery. An ecological risk assessment was conducted on the 16 species of sharks and 23 species of rays caught by the fishery.
  2. Eight species were classified to be at low risk, 28 species were at medium risk while three species – Rhynchobatus palpebratus (eyebrow wedgefish), Carcharhinus coatesi (Australian blackspot shark) and Maculabatis astra (blackspotted whipray), all endemic to New Guinea and northern Australia – faced the highest level of risk from the fishery at current fishing levels.
  3. There is potential for more vessels to enter the fishery in future, which is likely to elevate the risk for a greater proportion of elasmobranch species. Ongoing monitoring of bycatch levels, supported by biological and ecological studies on frequently caught species, is required to assess and manage risk in the future.
  4. The development and use of trawl excluder devices or bycatch reduction devices in this fishery have the potential to reduce bycatch levels and reduce risk levels.
  相似文献   

12.
The carnivorous gastropod Concholepas concholepas, known in Chile as “loco”, is a species present only along the Chilean coast line and in central-southern Perú showing high economic and ecological importance. Its fishery, which in the past decades has ranged between 828 (2001) and 24,828 (1980) metric tons per year [SERNAP, 2005. Servicio Nacional de Pesca: Anuarios estadísticos. (http://www.sernap.cl/paginas/publicaciones/anuarios/index_anuario.php)], is based exclusively on the exploitation of wild stocks. So far, there has been limited interest in tackling the biological and technical feasibility of cultivation of C. concholepas. Hence, the knowledge about its early ontogenetic stages (i.e., larval, early postmetamorphic and small juvenile) cultivation is still deficient. In this study we investigated, under laboratory and field conditions, C. concholepas survivorship, growth rates, feeding rates and the onset of sexual reproduction. Competent loco's larvae were collected in the field and metamorphosed in the laboratory to assess growth rates and survivorship during the first six months of postmetamorphic life. Moreover, using small juvenile C. concholepas of ca. 20 mm of peristomal length, collected in the field, we monitored for the body size and live weight traits in laboratory and field rearing conditions. The feeding of the early postmetamorphics and small juveniles was exclusively based in mono diets of the mussel Semimytilus algosus. The rearing of small juveniles was conducted in two consecutive phases, using two specially designed rearing apparatus. The biochemical content of our laboratory cultivated specimens was compared with values obtained from specimens collected in natural habitats. Their rapid growth and good survivorship makes this species suitable for rearing of cocktail-size specimens (50–60 mm) in less than a year. According to the growing rates reported in this study the legal commercial size of C. concholepas: 100 mm of PL would be reached under field and laboratory conditions in 1.65 and 2.64 years respectively. Moreover, it was found that in our rearing conditions C. concholepas reach sexual maturity in less than a year of benthic life. In summary, considering the findings about C. concholepas high growth rates, and low mortalities, we suggest that our rearing methodologies may be scaled up and implemented for the commercial aquaculture of this unique and valuable muricid.  相似文献   

13.
  1. Hammerhead sharks are represented by four species in India's marine fishery – Sphyrna lewini, Sphyrna mokarran, Sphyrna zygaena and Eusphyra blochii. This paper describes the hammerhead shark fishery in India during 2007–2018 and summarizes observations on the biology of S. lewini exploited along the Indian coast.
  2. Hammerhead sharks are caught by trawl nets, gillnets, seines and line gear, mostly as bycatch. Annual average landing of hammerhead sharks during 2007–18 was 639 t, with a low of 290 t in 2018, of which S, lewini was the dominant species, comprising 95% of landings. Hammerhead sharks formed nearly 1.31% of the total elasmobranch landings. About 54% of hammerhead sharks were landed by trawlers.
  3. Length range of S. lewini in regular landings was 36–300 cm total length (TL). The dominant size class was 30–100 cm TL; 79.5% of males and 83.2% of females measured between 40 and 100 cm TL. Length–weight relationship was derived as W = 0.0218*(L)2.634 and W = 0.0131*(L)2.769 for males and females, respectively.
  4. Overall sex ratio (F: M) was 1.3:1; below 100 cm TL, the sex ratio was skewed in favour of females. The length at first maturity of males was estimated as 168 cm. The length at first maturity of females was estimated at 239.6 cm. Fecundity ranged from 12–40, size at birth was 36–45 cm TL. Bony fishes were the preferred prey, followed by cephalopods.
  5. The S. lewini landings in India are dominated by juveniles and threatens sustainability of the stock. Capture of juvenile sharks can be excluded to a considerable extent through strict implementation of minimum legal size of capture, and a conservative minimum legal size of 220 cm is suggested for this species in Indian waters. Identification of recurring juvenile aggregation grounds, their spatio-temporal closures, gear restrictions and greater stakeholder awareness could lead to conservation of the resource and a sustainable fishery.
  相似文献   

14.
Reef-building corals are sensitive to excessive nitrogenous (N) compounds. To maintain levels of inorganic nitrogenous compounds low in coral aquaria, various technologies, mechanical, chemical and biological, have been applied. As one of the biological techniques, “live rock,” which can be defined as a dead coral skeleton covered with crustose coralline algae (CCA), has long been applied for coral aquaria. Until recently, however, there has been little evidence for the effectiveness of live rock in removal of N compounds from coral aquaria. Demonstrating comparative experiments with live rocks, here we report that the live rock is capable of removing N compounds and reduces the mortality of reef-building coral. We cultured the reef-building coral Acropora digitifera with the sea cucumber Holothuria atra as a natural nitrogen producer. H. atra increased the concentration of the inorganic N compounds (NH4+, NO3− and NO2−) that resulted in high coral mortality. The presence of the live rock remarkably reduced the concentrations and sustained a high coral photosynthetic activity. We detected the functional genes amoA and nirS within the live rock, suggesting the occurrence of both nitrifying and denitrifying bacteria. These results support the idea that “live rock” is an effective biofilter that can maintain water quality suitable for reef-building corals.  相似文献   

15.
Assessment of ecological sustainability for all species impacted by fishing is one of the most important and practical steps towards an Ecosystem Approach to Fisheries. We extend methods for Sustainability Assessment for Fishing Effects (SAFE) to assess diverse bycatch species in a multi-sector and multi-gear fishery. We develop methods for estimating fishing mortality rate, based on limited data, for demersal trawl, Danish seine, gillnet, and longline. The general approach involves estimating spatial overlap between species distribution and fishing effort distribution, catchability resulting from probability of encountering the gear and size-dependent selectivity, and post-capture mortality. We define three reference points (Fmsm, Flim, and Fcrash) and use six methods to derive these reference points. As an example, we apply this method to nearly 500 fish species caught in the Southern and Eastern Scalefish and Shark Fishery, a multi-sector and multi-gear fishery in Australia. We assess sustainability risk for all captured fish species in each sub-fishery and the cumulative impact across all the sub-fisheries. The results indicate that chondrichthyans are more vulnerable to fishing impact than teleosts, and that impact differs among sectors of the fishery. This method could be easily applied to other fisheries. However, the results may require fine tuning by other means such as expert judgment.  相似文献   

16.
Fleet dynamics was addressed for three cephalopod taxa of commercial interest, the squid Loligo vulgaris, the octopuses Octopus vulgaris and Eledone cirrhosa, and the cuttlefish Sepia officinalis, for 48 trawlers of the fish trawling fleet. Landing profiles (LP) were identified based on the species composition of the landings using hierarchical cluster analysis. Four out of a total of 12 different LP were related to cephalopods and other species associated with them.The effects on the landing proportions of a number of variables, year, season and vessel, are analysed for each of the species studied using generalized linear models (GLM). The factor “vessel”, including an ensemble of technical characteristics as well as the abilities of individual skippers, explained most of the model deviance, strongly reinforcing the existence of a fleet component dedicated to catch cephalopods. However, time also explains much of the variation found in the data.Seasonal alternation between landings of octopodidae and cuttlefish was observed within a small group of old trawlers operating mainly off the south coast, following the abundance cycles of these species. For a larger group of more modern trawlers, operating off the western coast, inter-annual shift between octopus and squid was found, together with a well marked seasonal pattern between the catches of cephalopods and horse mackerel.Spatial patterns of activity were identified using vessel monitoring system (VMS) data available for trawlers in Portugal, demonstrating the existence of cephalopod targeting strategies in Portuguese fish trawling activities.  相似文献   

17.
黄河入海泥沙年际通量对莱州湾渔业资源结构的影响   总被引：2，自引：0，他引：2  
根据2009年8月-2013年8月莱州湾海域渔业拖网调查数据,分析该海域渔业种群组成、优势种、空间分布和资源量的年际变动,以了解黄河入海泥沙通量对莱州湾渔业结构的影响.结果表明:(1)莱州湾渔业资源量整体呈下降趋势,主要以鱼类为主,甲壳类次之,头足类最少;鱼类中以中上层鱼类为主,网获量明显多于底层鱼类,但2011年8月底层鱼类稍多于中上层鱼类;(2)莱州湾渔业资源各年份的优势种有所变动,中上层鱼类和底层鱼类的优势种变动较大,甲壳类优势种变动较少,鱼类优势种组成存在年际更替现象,主要由经济价值高、个体大的种类向经济价值低、个体小的种类演替.主要优势种集中于斑鲦、矛尾鰕虎鱼、口虾蛄、小带鱼和日本枪乌贼等种类.2010年斑鲦大量暴发,为唯一优势种;(3)2009-2013年黄河入海泥沙年际通量与鱼类种数、底层鱼类数和渔业资源数存在显著相关性,与底层鱼类生物量存在极显著相关性.综上所述,黄河入海泥沙年际通量的变动对莱州湾渔业资源量和资源结构都产生了一定影响.  相似文献   

18.
Psorospermium haeckeli is a thick-walled, unicellular organism widely reported in European astacid crayfish. Its taxonomic status and life cycle have not been elucidated. It is often referred to as a “parasite”, but conclusive evidence has yet to be found. Recent examination of two North American crayfish species, Procambarus clarkii and Procambarus zonangulus, confirmed its presence in the south-central USA (Louisiana) with morphologies that differ from that of P. haeckeli. This form had been previously reported from Orconectes virilis in southern Canada. We report here the presence of this North American form of Psorospermium in additional North American crayfish including Orconectes immunis and Orconectes rusticus from the northern USA (Minnesota and Wisconsin), Procambarus alleni and Procambarus fallax from the southern USA (Florida), and Pacifastacus leniusculus from the western USA. We also confirm this Psorospermium in O. rusticus from eastern Canada (Ontario). It was not, however, confirmed in several additional southern crayfish species including Cambarus diogenes, Cambarellus puer, Fallicambarus fodiens, and Orconectes palmeri. We describe the morphological forms of this Psorospermium and conclude that it is present in many crayfish species in North America.  相似文献   

19.
虾类是东海区的主要捕捞对象之一。东海区的拖虾渔业以虾类为主要捕捞目标,发展之初对于促进捕捞结构调整、减轻主要经济鱼类的捕捞压力起了重要作用。但是随着该种作业方式生产规模的不断扩大、生产渔船和渔具的大型化,渔获物中经济虾类和兼捕幼虾的矛盾日益突出,对东海区的渔业资源造成较大程度的破环。本文主要介绍了东海区拖虾渔业的发展和资源概况,主要经济虾类的种类、分布、作业渔船的产量和数量变化,分析了东海区拖虾渔业中存在的问题和所采取的措施,并提出了解决问题的建议。  相似文献   

20.
One of the fundamental aims of the Ecosystem Approach to Fisheries Management is to ensure the long‐term sustainability of the fishery by protecting key life‐cycle habitats, such as recruitment areas. In this study, we apply a hurdle Bayesian hierarchical spatio‐temporal model that describes the abundance of European hake (Merluccius merluccius) recruits in the northern continental shelf of the Iberian Peninsula. Our findings clearly show four persistent nurseries, the main one being located along the continental shelf of the Artabrian gulf (off La Coruña). The preferential habitats identified for the hake recruits are areas within a bathymetric range of 120–200 m, with 15–16°C of Sea Surface Temperature, a Chl‐a concentration of 0.8–1.2 mg/m3 and low values of seabed rugosity (unconsolidated substrates). Searching for a compromise with fisheries, we also assess the degree of overlap of the main nursery areas with two fisheries footprints, a local one using Vessel Monitoring System data of trawl fishery of Marín, and a global one using Automatic Identification System data of different type of trawlers (bottom otter, beam and midwater trawls). The two fisheries footprints present different degree of overlapping in distinct areas, highlight the need of specific fleet‐adapted management rules in order to protect juvenile stages. We discuss that understanding the distributional patterns associated with key life stages, such as recruitment, and their interaction with fishing activities, is essential for applying appropriate spatial management measures and improving fishery sustainability.  相似文献   

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