Fisheries Research最新文献_第5页

Artisanal longline fishing for Greenland halibut (Reinhardtius hippoglossoides) operated under sea ice using a metal plate kite in northwest Greenland 在格陵兰岛西北部海冰下使用金属板风筝手工延绳钓格陵兰大比目鱼（Reinhardtius hippoglossoides）的情况

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-10-07 DOI: 10.1016/j.fishres.2024.107203

Kenzo Tanaka , Makoto Tomiyasu , Ryo Kusaka , Shin Sugiyama , Evgeny A. Podolskiy , Yasuzumi Fujimori

Understanding the deployment ranges and behavior of fishing gear in relation to fishery efficiency will help us grasp the potential impact of future shifts in the fishery on resources and fishing activities. Fisheries for Greenland halibut are conducted by boat in open water during the summer. However, in winter, fishermen travel to fishing grounds on the sea ice using dog sleds, drill holes in the ice, and deploy longlines using metal plate kites. While the scale of deployment varies between boat and ice longlining, the movement of kites used in ice longlining and their effect on the deployment range of the line is not well understood. We conducted experiments using an accelerometer to determine the underwater movement of kites and their effect on the horizontal range of longline deployment. This is the first report describing specific operational information on longline fishing under sea ice, specifically on the effects of the kite on longline deployment. The kite is attached to the leading end of the mainline and deploys the longlines horizontally as it moves downward towards the sea floor. When the kite and mainline are dropped into the sea, the kite extends the line horizontally while shifting forward-facing long side, and forward-aligned short side. The motion resembles a fluttering action primarily influenced by the Reynolds number and moment of inertia. When the mainline is held, the kite descends in a circular motion. With repeated fishing operations and the passage of time, the kite's movement is expected to decrease in both range and speed due to the buoyancy and tension of the mainline. These kite movements suggest that the deployment range of longlines could extend several hundred meters. Therefore, it can be inferred that the impact of winter ice fishing on the Greenland halibut stock is relatively low due to the limited deployment range of the longline when using the kite.

了解渔具的部署范围和行为与渔业效率的关系，将有助于我们掌握未来渔业变化对资源和渔业活动的潜在影响。格陵兰大比目鱼的捕捞活动在夏季由船只在开阔水域进行。然而，在冬季，渔民们使用狗拉雪橇前往海冰上的渔场，在冰上钻孔，并使用金属板风筝布放延绳。虽然船式延绳钓和冰上延绳钓的布放规模各不相同，但人们对冰上延绳钓中使用的风筝的运动及其对延绳钓布放范围的影响却不甚了解。我们使用加速度计进行了实验，以确定风筝的水下运动及其对延绳部署水平范围的影响。这是第一份描述海冰下延绳钓具体操作信息的报告，特别是风筝对延绳钓布放的影响。风筝连接在主线的前端，在向海底下移的过程中水平布放延绳。当风筝和主线落入海中时，风筝将钓线水平拉长，同时长线朝前，短线朝前。这种运动类似于飘动，主要受雷诺数和惯性矩的影响。当主线被握住时，风筝以圆周运动的方式下降。随着反复捕鱼作业和时间的推移，由于主线的浮力和张力，预计风筝的运动范围和速度都会减小。这些风筝运动表明，延绳钓的布放范围可以延伸几百米。因此可以推断，由于使用风筝时延绳钓的布放范围有限，冬季冰钓对格陵兰大比目鱼种群的影响相对较小。

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引用次数: 0

Influence of habitat enhancement and habitat degradation on spiny lobster populations in the Caribbean: An overview 生境改善和生境退化对加勒比海棘龙虾种群的影响：概述

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-10-05 DOI: 10.1016/j.fishres.2024.107193

Patricia Briones-Fourzán

Spiny lobsters are one of the most valuable fishing resources worldwide. These lobsters have a complex life cycle with a lengthy pelagic phase followed by a lengthier benthic phase, with several habitat shifts in some species. Finding adequate habitats is complicated for these lobsters, as they interact with different prey, predators, and competitors in subsequent habitats. This paper provides an overview of the characteristics of spiny lobster benthic habitats, focusing on two species from the wider Caribbean region, Panulirus argus and P. guttatus. Tropical spiny lobsters are omnivorous; therefore, food is not as limiting a component of habitat as is shelter, on which their survival greatly depends. Indeed, lack of appropriate shelter may result in population bottlenecks. This observation underlies the use of artificial structures (such as “casitas”) to enhance lobster habitats for fisheries and conservation purposes. Pros and potential cons of habitat enhancement are also reviewed. The other side of the coin is habitat degradation. Throughout the wider Caribbean and elsewhere, climate change –mostly resulting from anthropogenic stressors– and coastal development are increasing coastal pollution and eutrophication, seagrass loss, algal blooms, habitat fragmentation, coral reef degradation, and marine diseases, changing the habitat landscapes with potentially dire effects for spiny lobster populations. Because of the different habitats used by these two species throughout their benthic lives, P. guttatus is likely to be more vulnerable to coral reef degradation and the settling postlarvae and early juveniles of P. argus to degradation of seagrass and shallow hard bottom communities. Conservation of appropriate habitats for target species should be considered an important aim of ecosystem-based fisheries management.

刺龙虾是全球最宝贵的渔业资源之一。这些龙虾的生命周期很复杂，先是漫长的中上层阶段，然后是更长的底栖阶段，有些物种的栖息地会发生多次转移。由于龙虾在随后的栖息地中会与不同的猎物、捕食者和竞争者相互作用，因此寻找适当的栖息地对它们来说非常复杂。本文概述了棘龙虾底栖栖息地的特征，重点是大加勒比海地区的两个物种--Panulirus argus和P. guttatus。热带刺龙虾是杂食性动物；因此，食物对栖息地的限制不如栖息地那么大，而它们的生存在很大程度上依赖于栖息地。事实上，缺乏适当的栖息地可能会造成种群瓶颈。这一观点是利用人工结构（如 "卡西塔"）改善龙虾栖息地以达到渔业和保护目的的基础。此外，还回顾了改善栖息地的利弊。硬币的另一面是生境退化。在整个大加勒比海和其他地区，气候变化（主要是人为压力造成的）和沿海开发正在加剧沿海污染和富营养化、海草减少、藻类大量繁殖、栖息地破碎化、珊瑚礁退化和海洋疾病，从而改变了栖息地景观，对棘龙虾种群造成了潜在的严重影响。由于这两个物种在整个底栖生活期间使用的栖息地不同，古特龙虾可能更容易受到珊瑚礁退化的影响，而阿格斯龙虾的沉降后幼体和早期幼体则更容易受到海草和浅层硬底生物群落退化的影响。保护目标物种的适当栖息地应被视为基于生态系统的渔业管理的一个重要目标。

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引用次数: 0

Larval ontogeny enhances resilience to a patchy planktonic food supply in the American lobster (Homarus americanus) 幼虫的本体发育增强了美洲龙虾（Homarus americanus）对零星浮游食物供应的适应能力

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-10-04 DOI: 10.1016/j.fishres.2024.107179

Evelyn M. Layland , Emily Patrick , Molly Spencer , Rachel Lasley-Rasher , David M. Fields , Richard A. Wahle

The American lobster (Homarus americanus) plays an integral role in the coastal Northwest Atlantic as a benthic consumer and the target of the most valuable single-species fishery in North America. In the past decade, benthic recruitment of juvenile lobster has declined, even as egg production has increased, suggesting heightening levels of larval mortality. Recent correlative studies in the Gulf of Maine further suggest early-stage larval survival may be related to the supply and composition of planktonic foods. Despite these correlative studies and the economic importance of the species, relatively little is known about how larval lobster interacts with its prey in the pelagic environment. During these early developmental stages, lobster larvae undergo significant morphological changes which influence their ability to capture and handle prey. This study used a combination of laboratory-based feeding experiments and video recordings to examine changes in feeding behavior and ingestion rates between larval stages. Calculated Ivlev-type functional response curves were used to evaluate how larval ingestion rates vary with prey density and by larval stage on a suite of prey species. We observed dramatic stage-to-stage improvements in the capacity to pursue, capture, handle, and ingest specific prey, especially after the metamorphosis to the postlarval stage. The results highlight the vulnerability of the early life stages to low food densities. They also elucidate differences in the ability of specific prey taxa to evade predation by larval lobster. Quantifying the interactions between larval lobsters and their prey enhances our understanding of how this economically important species interacts with the pelagic food web, which fraction of available zooplankton represent viable food sources, and how lobster larvae may be impacted by altered prey availability associated with climate change.

美洲龙虾（Homarus americanus）在西北大西洋沿岸扮演着不可或缺的角色，既是底栖消费者，也是北美最有价值的单一物种渔业的捕捞对象。在过去十年中，即使产卵量增加，幼龙虾的底栖繁殖量也在下降，这表明幼体死亡率在上升。最近在缅因湾进行的相关研究进一步表明，早期幼体的存活可能与浮游生物食物的供应和组成有关。尽管进行了这些相关研究，而且该物种具有重要的经济意义，但人们对龙虾幼体如何在浮游环境中与猎物相互作用知之甚少。在这些早期发育阶段，龙虾幼体会发生显著的形态变化，从而影响其捕捉和处理猎物的能力。本研究采用实验室喂食实验和视频记录相结合的方法，研究不同幼体阶段的喂食行为和摄食率的变化。通过计算伊夫列夫型功能反应曲线来评估幼虫摄食率如何随猎物密度和幼虫阶段的不同而变化。我们观察到，在追逐、捕捉、处理和摄取特定猎物的能力方面，幼体阶段与阶段之间的差异非常明显，尤其是在变态到后幼体阶段之后。这些结果突显了生命早期阶段对低食物密度的脆弱性。它们还阐明了特定猎物类群逃避幼体龙虾捕食能力的差异。量化龙虾幼体与其猎物之间的相互作用有助于我们更好地了解这一具有重要经济价值的物种如何与浮游食物网相互作用，现有浮游动物中哪一部分是可行的食物来源，以及龙虾幼体如何受到与气候变化相关的猎物可用性改变的影响。

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引用次数: 0

Post-harvest losses of marine fish at fishers in Bangladesh 孟加拉国渔民捕捞海鱼后的损失

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-10-03 DOI: 10.1016/j.fishres.2024.107198

Anup Kumar Mandal , Md. Mamun Or Rashid , Md. Sujahangir Kabir Sarkar , Badiuzzaman , Md. Sazedul Hoque , Afjal Hossain

The marine fishing industry is considered as one of Bangladesh's most important contributors to the nation's economy. The post-harvest losses of marine fish have a substantial impact on the contribution of the industry. Therefore, the aim of this study was to assess post-harvest losses of marine fish at fishermen level and to identify the factors that influence post-harvest losses. In-person interviews were conducted in two coastal divisions of Bangladesh to collect data from 643 fishermen, which was then analyzed using multiple regression models. Results showed that the total post-harvest losses of marine fish in Bangladesh were 17.75 % of total caught, with physical and market losses accounting for 9.86 % and 90.14 %, respectively. The use of inadequate ice and uninsulated containers was estimated to increase post-harvest losses of marine fish by 40 %, all else being equal. Earning members, inadequate storage, longer time attached to the net, delayed marketing, and tide pressure were statistically significant and positively correlated with post-harvest losses, whereas family members and fish finder were negatively associated with post-harvest losses. This study thus recommends that those who harvest marine fish should be aware of the parameters they choose that affect post-harvest losses.

海洋捕捞业被认为是孟加拉国对国家经济贡献最大的行业之一。海鱼捕捞后的损失对该行业的贡献有着重大影响。因此，本研究旨在从渔民层面评估海鱼捕捞后的损失，并确定影响捕捞后损失的因素。研究人员在孟加拉国的两个沿海分区进行了面对面访谈，收集了 643 名渔民的数据，然后使用多元回归模型对这些数据进行了分析。结果显示，孟加拉国海鱼捕捞后的总损失为总捕捞量的 17.75%，其中实物损失和市场损失分别占 9.86% 和 90.14%。据估计，在其他条件相同的情况下，使用不适当的冰块和不隔热的容器会使海鱼收获后的损失增加 40%。有收入的成员、储存不足、附着在渔网上的时间较长、延迟销售和潮汐压力与捕捞后损失呈显著正相关，而家庭成员和探鱼器与捕捞后损失呈负相关。因此，这项研究建议，捕捞海鱼的人应注意他们所选择的会影响捕捞后损失的参数。

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引用次数: 0

Measuring, interpreting and monitoring economic efficiency in South Australia’s Spencer Gulf and West Coast Prawn Fisheries 测量、解释和监测南澳大利亚斯潘塞湾和西海岸对虾渔业的经济效益

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-10-02 DOI: 10.1016/j.fishres.2024.107191

Stephanie McWhinnie , Sean Pascoe , Peggy Schrobback , Eriko Hoshino

Fishers and fishing vessels are not homogeneous, with their level of catch affected by the choice of physical inputs such as engine size, boat size and the type of fishing technology employed, as well as less tangible factors such as skipper skill and experience. Economic output also vitally depends upon the value of the product in the market and the cost of inputs. These differences in the ability of individual fishers to catch fish, and create economic returns, can be assessed through the application of efficiency analysis. This paper provides an empirical examination of efficiency indicators in the South Australian Spencer Gulf and West Coast Prawn Fisheries. Applying data envelopment analysis (DEA) to a unique vessel-level dataset that includes both quantity and value information, we estimate measures of efficiency in these input-controlled fisheries where effort decisions are made in real-time using a participative management approach. We find that quantity and value-based efficiency measures are relatively high but that the variability of value-based measures is increasing. This increasing heterogeneity in value, despite the homogeneity in quantities, has potential implications for pressures on cooperative management going forwards as fishers pursue different business strategies. Comparing the measures of efficiency to direct measures of individual profit, we find a divergence: technical and cost measures of efficiency are more strongly positively related to short-run economic performance while revenue-efficiency is more strongly positively correlated with long-run economic performance, suggesting that different efficiency metrics may be required for short- and long-run monitoring.

渔民和渔船并不是千篇一律的，他们的渔获量会受到有形投入（如发动机大小、渔船大小和采用的捕鱼技术类型）的选择，以及船长技能和经验等非有形因素的影响。经济产出也在很大程度上取决于产品在市场上的价值和投入成本。个体渔民在捕鱼能力和创造经济收益方面的这些差异可以通过应用效率分析进行评估。本文对南澳大利亚斯潘塞湾和西海岸对虾渔业的效率指标进行了实证研究。我们对包含数量和价值信息的独特渔船级数据集进行了数据包络分析（DEA），估算了这些投入控制型渔业的效率指标。我们发现，以数量和价值为基础的效率测量值相对较高，但以价值为基础的测量值的变异性正在增加。尽管在数量上存在同质性，但价值上的这种日益增长的异质性对合作管理的未来压力具有潜在影响，因为渔民追求的是不同的商业战略。将效率衡量标准与直接衡量个体利润的标准进行比较，我们发现了一个分歧：技术和成本效率衡量标准与短期经济绩效的正相关性更强，而收入效率与长期经济绩效的正相关性更强，这表明短期和长期监测可能需要不同的效率衡量标准。

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引用次数: 0

Exploring the use of otolith shape analysis to identify the stock spatial structure of dusky rockfish (Sebastes variabilis) 探索利用耳石形状分析确定暗色岩鱼（Sebastes variabilis）种群的空间结构

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-10-01 DOI: 10.1016/j.fishres.2024.107189

Todd T. TenBrink , Jane Y. Sullivan , Christopher M. Gburski

Dusky rockfish (Sebastes variabilis) is a commercially valuable groundfish species in Alaska waters, with its highest abundance and fishery catch occurring in the Gulf of Alaska (GOA), and lesser abundance and catch occurring throughout the Aleutian Islands and southeastern Bering Sea. Despite its commercial importance, information regarding stock structure of dusky rockfish has been data-limited. In this study, otolith shape analysis was used to evaluate the stock structure of dusky rockfish across five geographical subareas exhibiting ecological differences in the GOA and Bering Sea and Aleutian Islands (BSAI), where dusky rockfish are managed as two separate stocks. A combination of size and shape indices, wavelet, and elliptic Fourier descriptors were examined from left and right-side otoliths collected from these regions (n = 522). Individual variation existed across subareas. Wavelet and elliptic Fourier descriptors indicated that mean otolith shapes were partitioned between the two management regions but also showed a high degree of overlap among subareas. Classification accuracies of otoliths to their subarea of origin through linear discriminant analysis (LDA) were variable (6.3–73.5 % and 15.4–65.8 % correctly classified for the elliptic Fourier and wavelet analyses, respectively). The highest classification rates were found between the western GOA and eastern Aleutian Islands, contributing to the observed differences between management regions and providing some support for current management paradigms. Dusky rockfish exhibited low to moderate overall classification rates (43.9–52.2 %), suggesting minimal stock structure within Alaska waters. This study highlights the utility of otolith shape analysis as a stock discrimination tool, and results will help refine further investigations and support fishery management in Alaska.

暗色石首鱼（Sebastes variabilis）是阿拉斯加水域中一种具有商业价值的底层鱼类，在阿拉斯加湾（GOA）的丰度和渔获量最高，在阿留申群岛和白令海东南部的丰度和渔获量较低。尽管暗色石首鱼具有重要的商业价值，但有关其种群结构的资料却十分有限。在这项研究中，利用耳石形状分析评估了五大地理亚区的褐石首鱼种群结构，这五大地理亚区显示了大洋洲和白令海及阿留申群岛（BSAI）的生态差异，其中褐石首鱼被作为两个独立的种群进行管理。研究人员对从这些区域收集的左侧和右侧耳石（n = 522）进行了尺寸和形状指数、小波和椭圆傅立叶描述符的组合研究。各亚区之间存在个体差异。小波和椭圆傅立叶描述符表明，平均耳石形状在两个管理区之间是分区的，但也显示出亚区之间的高度重叠。通过线性判别分析（LDA）将耳石分类到原产地亚区的准确率不一（椭圆傅里叶分析和小波分析的正确分类率分别为 6.3%-73.5% 和 15.4%-65.8%）。全球海洋观测系统西部和阿留申群岛东部的分类率最高，这说明管理区域之间存在差异，并为当前的管理模式提供了一些支持。暗色石首鱼表现出低到中等的总体分类率（43.9-52.2%），表明阿拉斯加水域内的种群结构最小。这项研究强调了耳石形状分析作为种群区分工具的实用性，研究结果将有助于完善进一步的调查，支持阿拉斯加的渔业管理。

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引用次数: 0

Quantifying non-target seahorse fisheries and domestic traditional medicine-based trade in Malaysia 量化马来西亚的非目标海马渔业和国内传统医药贸易

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-09-28 DOI: 10.1016/j.fishres.2024.107188

Reana May Yen Ng , Adam Chee Ooi Lim , Chin Nurhiqwanalina Binti Henry Chin Siew Lee , Norazliana Binti Abdul Majib , Muhammad Ali Syed Hussein , Amy Yee-Hui Then

Seahorses (Hippocampus spp.) are sold primarily for traditional medicine (TM) uses in Southeast Asia. Although Malaysia is reportedly an important global seahorse exporter, documentation on the current extent of seahorse catch and trade of seahorse-based TM within the country is limited. This study aimed to quantify patterns of seahorse bycatch, gear-specific biological parameters of caught seahorses, and trade characteristics in Malaysia. Questionnaire-based fisher and TM surveys were administered nationwide from March 2021 to March 2023. Seventy-one percent of fisher respondents (612 out of 860) reported catching seahorses, with gill or drift net fishers (73 %) more likely to have caught seahorses than trawlers (12 %). Significant spatial differences in species composition was observed between Peninsular Malaysia and Malaysian Borneo (Sabah state). The total estimated annual seahorse catch within Malaysia was approximately 3376 kg per year, with 77 % of the catch attributed to gill or drift nets and 23 % to trawling operations. Almost half (40 %) of traditional Chinese medicine (TCM) practitioners/ traders (n = 138), 3 % of Malay TM practitioners (n = 3), and 88 % of other TM traders (n = 7) reported selling seahorse species. This study is one of the first to quantify the often overlooked but critical contribution of small-scale fisheries, especially gill and drift nets, towards seahorse bycatch. The current supply volume and selling price of seahorses were observed to be relatively high, while the present-day demand was reportedly low. Almost half of TCM practitioners/ traders interviewed were still actively selling seahorses, indicating that there is still considerable demand. To ensure the sustainability of seahorse populations in Malaysia, efforts in both small-scale and trawl fisheries must be reduced while strictly enforcing seahorse trade regulations.

海马（Hippocampus spp.）在东南亚主要作为传统药物（TM）出售。尽管据报道马来西亚是全球重要的海马出口国，但有关目前海马捕获量和国内以海马为基础的传统医药贸易的文献资料却很有限。本研究旨在量化马来西亚的海马兼捕模式、捕获海马的特定渔具生物参数和贸易特征。2021 年 3 月至 2023 年 3 月，在全国范围内开展了基于问卷的渔民和 TM 调查。71%的渔民受访者（860 位受访者中有 612 位）报告捕获了海马，刺网或流网捕鱼者（73%）比拖网捕鱼者（12%）更有可能捕获海马。在马来西亚半岛和马来西亚婆罗洲（沙巴州）之间，物种组成存在显著的空间差异。据估计，马来西亚每年的海马总捕获量约为 3376 千克，其中 77% 的捕获量来自刺网或流网，23% 来自拖网作业。近一半（40%）的传统中医（TCM）从业者/贸易商（n = 138）、3%的马来传统中医（n = 3）和 88%的其他传统中医贸易商（n = 7）报告出售海马物种。这项研究是首批量化小型渔业（尤其是刺网和流网）对海马误捕的经常被忽视但却至关重要的贡献的研究之一。据观察，目前海马的供应量和销售价格相对较高，而据说目前的需求量较低。几乎一半的受访中医/贸易商仍在积极销售海马，这表明仍有相当大的需求。为确保马来西亚海马种群的可持续发展，必须减少小规模和拖网捕捞，同时严格执行海马贸易法规。

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引用次数: 0

Identifying statistical interaction networks in marine communities using multivariate time series analysis: An application in the Gulf of Lions 利用多变量时间序列分析确定海洋群落中的统计交互网络：狮子湾的应用

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-09-28 DOI: 10.1016/j.fishres.2024.107177

Cyria Meriem Bensebaini , Grégoire Certain , Sophie Gourguet , Olivier Thébaud , Tarek Hattab , Norbert Billet , Angélique Jadaud , Jean-Marc Fromentin

The need for an ecosystem-based approach to fisheries management is widely recognized. Designing ecosystem models for management purposes requires the identification of key interactions and environmental forcing that drive the dynamics of fish stocks. This can be a very challenging task given the complexity of interactions, which determine the evolution of marine ecosystems. To overcome this difficulty, this study proposes a statistical approach based on multivariate time series analysis to identify the main biotic and abiotic interactions using as a case study of a complex and exploited marine ecosystem, the Gulf of Lions (GOL) in the Mediterranean Sea. To do so, first, pairwise Granger causality tests were performed to detect and select the strongest interactions and drivers, then followed by Multivariate Auto-Regressive (MAR) modelling techniques to evaluate the relevance of the selected causal relationships in a multivariate system. The results led to the identification of three statistical interaction networks (SINs) of moderated complexity. The first showed statistical interactions between blackbellied angler (Lophius budegassa), hake (Merluccius merluccius), grey gurnard (Eutrigla gurnardus), and John dory (Zeus faber), as well as the influence of phosphate concentration. The second focused on blackbellied angler, red mullet (Mullus barbatus), anchovy (Engraulis encrasicolus), under the combined influence of demersal trawlers, Sea Surface Temperature (SST) and nitrate concentration. Horned octopus (Eledone cirrhosa), capelan (Trisopterus capelanus), and sardine (Sardina pilchardus) were also investigated under the influence of nitrate concentration. These SINs can serve as a basis to build models of intermediate complexities to describe the dynamics of the main fish stocks of the GOL.

以生态系统为基础的渔业管理方法的必要性已得到广泛认可。为管理目的设计生态系统模型需要确定驱动鱼类种群动态的关键相互作用和环境作用力。鉴于决定海洋生态系统演变的相互作用的复杂性，这可能是一项极具挑战性的任务。为了克服这一困难，本研究提出了一种基于多变量时间序列分析的统计方法，以地中海狮子湾（GOL）这一复杂且受开发利用的海洋生态系统为例，确定主要的生物和非生物相互作用。为此，首先进行了成对格兰杰因果检验，以检测和选择最强的相互作用和驱动因素，然后采用多元自回归（MAR）建模技术，以评估所选因果关系在多元系统中的相关性。结果确定了三个复杂程度适中的统计互动网络（SIN）。第一个显示了黑腹鮟鱇（Lophius budegassa）、无须鳕（Merluccius merluccius）、灰鳕（Eutrigla gurnardus）和约翰海鲂（Zeus faber）之间的统计交互作用，以及磷酸盐浓度的影响。第二个研究重点是底栖拖网渔船、海面温度（SST）和硝酸盐浓度共同影响下的黑腹鮟鱇、红鲻（Mullus barbatus）和凤尾鱼（Engraulis encrasicolus）。此外，还研究了硝酸盐浓度对角章鱼（Eledone cirrhosa）、毛鳞鱼（Trisopterus capelanus）和沙丁鱼（Sardina pilchardus）的影响。这些 SIN 可作为建立中等复杂程度模型的基础，以描述全球海洋观测系统主要鱼类种群的动态。

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引用次数: 0

Amending the European fishing fleet segmentation based on machine learning and multivariate statistics 基于机器学习和多元统计修正欧洲捕鱼船队的划分

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-09-27 DOI: 10.1016/j.fishres.2024.107190

E. Sulanke , V. Rubel , J. Berkenhagen , M. Bernreuther , T. Stoeck , S. Simons

Considering the critical issue of overexploited stocks due to overfishing, the EU’s Data Collection Framework (DCF) was established. Within the DCF, member states collect and analyze data relevant to sustainable fisheries management. To evaluate the status of fisheries, it is necessary to categorize fishing fleets into fleet segments. However, the current DCF segmentation is primarily based on technical vessel parameters, such as vessel length and predominant fishing gear, which often do not accurately represent the fishing activities of the vessels. To address this, we developed an alternative fleet segmentation approach that provides a more realistic overview of fishing activities. This approach utilizes multivariate statistics and is coupled with machine learning techniques for automatization. Applying this approach to two decades of German fisheries data resulted in a data set with fewer segments compared to the DCF approach, which represented the actual fishing strategies more closely. The comparison of biological stock health indicators calculated for both the current and the novel segmentation schemes revealed that the current scheme often misses signs of segments relying on overexploited stocks. The machine learning technique applied showed high classification accuracy, with misclassifications being rare and only occurring in segments with overlapping catch composition. Since machine learning enables almost perfect allocation to the revised segments, we expect a successful implementation of this protocol for future fleet segmentation. This approach is highly suitable for data collection and analysis procedures and can serve as a standard tool. Therefore, this novel approach can contribute to the improvement of fishing fleet analyses and policy advice for better fisheries management.

考虑到过度捕捞导致种群过度开发这一关键问题，欧盟建立了数据收集框架（DCF）。在 DCF 框架内，成员国收集并分析与可持续渔业管理相关的数据。为了评估渔业状况，有必要将捕鱼船队分为船队分段。然而，目前的 DCF 划分主要基于船舶技术参数，如船舶长度和主要渔具，而这些参数往往不能准确代表船舶的捕捞活动。为了解决这个问题，我们开发了另一种船队划分方法，可以更真实地概括捕捞活动。这种方法利用多元统计并结合机器学习技术实现自动化。将这种方法应用于二十年的德国渔业数据，得出的数据集与 DCF 方法相比，分段更少，更贴近实际捕捞策略。对当前和新型分段方案计算出的生物种群健康指标进行比较后发现，当前方案往往会遗漏依赖于过度开发的种群的分段迹象。应用的机器学习技术显示出很高的分类准确性，误分类很少发生，而且只发生在渔获量构成重叠的部分。由于机器学习几乎可以完美地分配到修订后的分段，我们期待在未来的船队分段中成功实施这一方案。这种方法非常适合数据收集和分析程序，可以作为一种标准工具。因此，这种新方法有助于改进渔船队分析和政策建议，从而改善渔业管理。

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引用次数: 0

Environmental DNA reveals spatial and temporal variation in fish communities before the 10-year fishing ban in the Poyang Lake Basin 环境 DNA 揭示鄱阳湖流域十年禁渔期前鱼类群落的时空变化

IF 2.2 2区农林科学 Q2 FISHERIES

Fisheries Research

Pub Date : 2024-09-27 DOI: 10.1016/j.fishres.2024.107192

Chunhua Zhou , Shaoqing Jian , Zhizhong Jiang , Jinping Chen , Shan Ouyang , Xiaoping Wu

Poyang Lake is the largest freshwater lake in China, and its unique ecosystem is an important biodiversity reservoir. Fish play an important role in the aquatic ecosystem of Poyang Lake. Accurate assessment of fish species diversity and community composition is essential for studies of fish ecology and conservation management. In this study, environmental DNA metabarcoding was used to analyze fish diversity and community structure in different habitats and seasons in the Poyang Lake Basin. A total of 52 fish species were identified, and limnicolous fish were the most abundant; most fish were omnivorous and small. The fish diversity index was highest in the spring and in the main lake area of Poyang Lake. Cluster analysis and non-metric multidimensional scaling analysis revealed significant differences in fish community structure among habitats. Water temperature and pH were the main environmental factors affecting fish community structure in the Poyang Lake Basin. Non-invasive environmental DNA monitoring methods could provide an important auxiliary method for monitoring fishery resources during the 10-year fishing ban period. This study provides basic information on the fish resources in the Poyang Lake Basin and has implications for fishery management and the development of ecological protection policies.

鄱阳湖是中国最大的淡水湖，其独特的生态系统是重要的生物多样性库。鱼类在鄱阳湖水生生态系统中发挥着重要作用。准确评估鱼类物种多样性和群落组成对鱼类生态学研究和保护管理至关重要。本研究利用环境 DNA 代谢编码技术分析了鄱阳湖流域不同生境、不同季节的鱼类多样性和群落结构。研究共鉴定出52种鱼类，其中以鳞翅目鱼类最多；大多数鱼类为杂食性鱼类，体型较小。鱼类多样性指数在春季和鄱阳湖主湖区最高。聚类分析和非度量多维尺度分析表明，不同生境的鱼类群落结构存在显著差异。水温和pH值是影响鄱阳湖流域鱼类群落结构的主要环境因子。无创环境DNA监测方法可为十年禁渔期渔业资源监测提供重要的辅助方法。本研究提供了鄱阳湖流域鱼类资源的基本信息，对渔业管理和生态保护政策的制定具有一定的指导意义。

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引用次数: 0