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山东近海口虾蛄单位补充量渔获量评估 总被引：2，自引：1，他引：1
为完善口虾蛄的基础生物学资料,并为口虾蛄资源的管理提供科学指导和理论依据,本研究根据2016至2017年山东近海渔业资源底拖网调查获得的口虾蛄体长、体质量数据,估算了口虾蛄的生长、死亡参数,构建了基于体长结构的单位补充量渔获量(YPR)模型,研究口虾蛄的资源动态和管理策略。采集调查口虾蛄样品共5028尾,体长—体质量关系的表达式为W=0.0145L2.88,为负异速生长;使用ELEFAN方法估算出口虾蛄的渐进体长L∞为19.87 cm,生长速率K为0.62 a−1。口虾蛄的生长表现出明显的季节性变化规律,生长参数的季节振幅C为0.76,10月份生长最快,4月份生长最慢。通过体长转换的渔获曲线估算出口虾蛄的总死亡系数Z为3.24 a−1,根据不同方法估算自然死亡系数M的范围为0.75~1.27 a−1,捕捞死亡系数F的估算范围为1.96~2.49 a−1,开发率的均值为0.67。YPR模型结果显示,随着F增大,YPR值呈现先上升后下降的趋势,生物学参考点F0.1和Fmax的值分别为0.92a−1和1.88a−1。口虾蛄资源处于过度开发的状态,应降低捕捞压力,同时调整开捕体长,以维持口虾蛄渔业资源量和渔获量。 相似文献
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东海中华管鞭虾种群动态及持续渔获量分析 总被引：1，自引：0，他引：1
中华管鞭虾为东海区桁杆拖虾和沿岸定置张网作业重要的渔获对象。本文根据2006-2008年桁杆拖虾监测调查数据整理的各月体长频率数据,应用FiSATⅡ软件分析结果表明：Von Bertalanff生长方程的参数K=1.2,极限体长L∞=112.88mm,t0=0.267;根据Pauly经验公式估算的自然死亡系数M=2.03606;由变换体长渔获曲线法估算的总死亡系数Z=4.71,利用率E=56.77%,开捕体长Lc=65.32mm;应用体长VPA方法估算的年平均资源量为47.74×10^9ind、2.58×10^4t。通过单位补充量产量、产值分析表明,该群体利用合理,开捕体长亦处最佳位置,若降低10%左右的捕捞努力量水平,既能使产值最大化（4.92亿元）,又能实现中华管鞭虾的可持续利用。 相似文献
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利用2012年3月-2013年2月在鄱阳湖通江水道进行的定置网渔获物调查的数据,运用软件FiSAT II对翘嘴鲌(Culter alburnus)的生长参数以及种群补充模式进行了估算。结果显示,鄱阳湖通江水道翘嘴鲌体长范围为93-645 mm;体长(L, mm)和体重(W, g)的关系式为W = 0.9×10-5L3.029 (R2=0.975, n = 317),von Bertalanffy生长方程的各参数：渐近体长L∞= 677.25 mm,生长系数K= 0.140,理论生长起点年龄t0 = -0.854。总死亡系数Z=1.514/a,自然死亡系数M=0.173/a,捕捞死亡系数F = 1.341/a。鄱阳湖通江水道翘嘴鲌开发率E=0.886,资源处于过度利用状态。种群补充模式表明,鄱阳湖通江水道翘嘴鲌种群补充期在4–8月。因此,建议适当延长鄱阳湖的禁渔期,以利于其资源的恢复与保护。 相似文献
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鱼类最佳体长频率分析组距研究 总被引：12，自引：4，他引：8
随着计算机技术的发展,近几年以鱼类体长频率为基础估算鱼类生物学特征值的体长频率分析法迅速被广泛应用,而确定体长分组组距是开展鱼类体长频率分析的必要步骤,但往往不被重视,常被随意采用为1mm、5mm或10mm等。为了尽量减少误差,本研究根据1997年12月至1998年12月在珠江口水域尖尾罟网和掺缯网周年月度渔业资源调查中康氏小公鱼（Stolephorus commersoni）和棘头梅童鱼（Collichthys lucidus）的生物学测定资料,分别以不同的体长分组组距重构体长频率组成数据,采用FAO推出基于ELEFAN技术的FiSATⅡ软件估算渐近体长L∞和生长系数K值,进一步估算鱼类资源开发参数（Z,M,F,E）,分析以不同体长分组组距为基础估算结果的差异。结果表明,以相差较大的不同分组组距重构体长频率组成数据来估算渐近体长L∞、生长系数K和资源开发参数均有明显的差异,建议以体长全距、体长标准差和样品数量等影响因素来共同确定某种鱼类的体长分组组距,从而提高估算结果的可信度,以达到定量分析鱼类生物学特征值的目的。 相似文献
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闽东北外海底层流刺网作业渔获的银方头鱼群体由Ⅰ-Ⅺ龄11个世代构成，以Ⅱ、Ⅲ和Ⅳ龄占优势；体长优势组为210-270mm，体重优势组为200-400克，体长与体重的关系W=2.1120×10-5×L2.9964，r=0.9970。初次性成熟年龄为Ⅱ-Ⅲ龄，最小性成熟个体体长为190mm，在4-8月均有产卵活动；按VonBantanffy方程拟合生长参数L∞=436.21mm，W∞=1715.05g，K=0.2357，t0=-0.9542，体重生长拐点年龄为3.702龄。 相似文献
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岳阳中洲渔场鳙鱼年龄与生长的研究 总被引：1，自引：0，他引：1
根据2002年对岳阳中洲鱼场费家湖鳙鱼的取样调查分析,对该湖泊中鳙鱼的年龄生长进行了初步研究,计算出其体长与鳞半径相关为L=4.4285+14.0799R,体长与体重的关系式为W=3.2415×10-5L2.8759。确定其Von-Bertalanffy生长方程,得出其生长参数为L∞=78.3316詐,W∞=9.0682詔,K=0.2089,t0=-1.497a。通过其生长速度和加速度曲线反映生长过程的变化特点,确定了其生长拐点ti=3.76a,对指导生产和捕捞有重要意义。 相似文献
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2011-2012年在乌江思南江段采集454尾(雌性298尾,雄性109尾,性别不辨47尾)泉水鱼(Pseudogyrincheilus procheilus),以鳞片作为材料对年龄进行鉴定,利用软件FISAT-II处理体长与年龄数据,对其生长方程、生长拐点等生物学特征进行了研究。结果表明,泉水鱼鳞片为圆鳞,年轮主要表现为普通切割型与普通疏密型;年龄组成为1~4龄,其中以2~3龄为主;1~4龄,体长增长率为47.4%,雌性体长增长率达50.4%,雄性体长增长率为35.0%,体重增长率为438.5%,雌性体重增长率为485.1%,雄性体重增长率为275.9%;体重(W)与体长(L)呈幂指数关系:W=2×10-6L3.4784(R2=0.8824),雌鱼为:W=3×10-6L3.4002(R2=0.8505),雄鱼为:W=2×10-5L3.019(R2=0.8112);体长(L)和鳞径(S)呈幂函数相关:L=92.597S0.5458;Von Bertalanfy生长方程的各参数为:渐进体长L∞=278.10 mm,生长系数k=0.22,t0=-1.80;雌鱼各参数为:L∞=355.01 mm,k=0.14,t0=-2.38;雄鱼各参数为:L∞=224.04 mm,k=0.32,t0=-1.72,雄鱼达到渐进体长的速度比雌鱼要快得多;体长生长速度和加速度不具拐点,生长速度随年龄增加而递减,生长加速度始终为负值,随年龄增加而增大;体重生长速度和加速度都具有拐点,拐点年龄ti=3.87,拐点体长Li=198.22 mm,拐点体重Wi=195.59 g。结合泉水鱼生长拐点年龄和性成熟年龄,为保护乌江思南泉水鱼资源,建议以180 mm为最小捕捞个体的体长。 相似文献
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2018年3月—2019年9月,每月对山东海阳近岸流刺网渔船的主要渔获物口虾蛄(Oratosquillaoratoria)进行跟踪采样,测定样品的体长和体质量,鉴定摄食强度和雌性的卵巢发育程度,计算渔获物中雌、雄的比例,对口虾蛄的渔业生物学进行分析。结果显示,流刺网全年口虾蛄渔获物中,雌、雄比例为1∶1.03,4月和12月的雌、雄样品平均体长差异不显著(P>0.05),其余月份均存在显著差异(P<0.05)。雌性口虾蛄全年优势体长为100~140 mm,优势体质量为10~40 g;雄性口虾蛄优势体长为110~150 mm,优势体质量为20~50 g;除12月外,其余月份雌、雄样品体长分布均存在显著差异(P<0.05)。雌性口虾蛄全年样品性腺成熟度在Ⅰ~Ⅳ期,Ⅲ期和Ⅳ期个体主要出现在4—5月及10月—次年1月;雌性有2个性成熟高峰期,分别为5月和1月。10月雌、雄口虾蛄空胃率全年最低,体长相对增长速率最高。雌性口虾蛄体长与体质量关系为W=5.39×10–5 L2.7098(R2=0.8254,P<0.05),雄性口虾蛄体长与体质量关系为W=2.62×10–5L2.8744(R2=0.7986,P<0.05)。流刺网渔获物中雌、雄口虾蛄群体结构具有一定的差异。 相似文献
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Luca Ceriola Paolo Accadia Piero Mannini Fabio Massa Nicoletta Milone Nicola Ungaro 《Fisheries Research》2008,92(2-3):255-267
The state of demersal fishery in the Southern Adriatic Sea (GFCM-GSA 18, Central Mediterranean), years 1996–2003, from a biological, social and economic point of view was analysed using 47 indicators: 22 biological indicators obtained from fishery-independent data through yearly experimental bottom trawl surveys (“Medits” Programme), and 25 socio-economic indicators estimated from fishery-dependent data, available from the monitoring system of the Italian Institute for Economic Research on Fisheries and Aquaculture (IREPA). Biological indicators were applied for “single-species” (Eledone cirrhosa, E. moschata, Illex coindetti, Merluccius merluccius, Mullus barbatus, Nephrops norvegicus, Parapenaeus longirostris, Raja clavata, Zeus faber) and for “multi-species” analysis. Economic indicators describing economic performance, productivity, costs and prices, and the overall economic sustainability of fishery were estimated. Social indicators and a general indicator summarising social sustainability were also considered. Indicators’ values were displayed using the Traffic Light system. Both fishery-independent and fishery-dependent indicators highlighted a progressive decline of the trawl fishery system in the GSA 18. This decline was mainly related to the ongoing depletion of the traditional fishery target species (mostly long-living, late-maturing species) partially replaced by the increase of traditional accessory species (generally short-living species), as well as to the reduction of productivity and increasing costs. The whole procedure was proposed as a contribution to the identification and applicability of bio-economic indicators for fishery management purposes. 相似文献
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Melissa A. Karp Stephanie Brodie James A. Smith Kate Richerson Rebecca L. Selden Owen R. Liu Barbara A. Muhling Jameal F. Samhouri Lewis A. K. Barnett Elliott L. Hazen Daniel Ovando Jerome Fiechter Michael G. Jacox Mercedes Pozo Buil 《Fish and Fisheries》2023,24(1):71-92
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
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为了明晰东海区单层流刺网对棘绿鳍鱼的选择性特征,开展不同网目尺寸(45、50和55 mm)和网片高度(6和10 m)的单层流刺网生产实验。结果显示,不同实验网渔获物中棘绿鳍鱼体长频率呈单峰分布;选用Normal、Lognormal和Gamma模型对渔获数据进行拟合,并使用极大似然法估算模型参数,似然比卡方检验和赤池信息系数(AIC)比较表明,Lognormal模型拟合效果最佳,其卡方值为30.65,明显小于临界值,AIC值为147.78,模型曲线向右倾斜明显,峰值左侧选择率递增较快,右侧下降缓慢,与原始数据相符;50 mm网目50%选择性体长为123 mm,有效捕捞体长范围为123~209 mm;根据遭遇网具的棘绿鳍鱼资源结构估算结果,实验海域棘绿鳍鱼体长频率呈正态分布,优势体长范围为125~185 mm,与早期研究结果相近;50 mm网目有效捕捞体长范围与当前资源优势体长范围相近,可实现捕捞效率的最大化;总体上两种高度(6和10 m)实验网渔获物中,棘绿鳍鱼体长频率分布相似,优势体长范围相近,上述两种网片高度对棘绿鳍鱼资源的影响差异不显著。上述研究结果可为近海渔业生产和管理提供参考。 相似文献
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鱼类体长-体重关系参数估计的准确与否影响进一步的渔业资源评估和管理。不同采样设计获得的生物学数据,对鱼类体长-体重关系参数b估计可能会有一定的影响。本文基于2013-2014年在黄河口水域调查获得的矛尾虾虎鱼(Chaemrichthys stigmatias)体长、体重数据,采用计算机模拟重抽样方法,选取相对估计误差和相对偏差两个指标,比较了不同采样设计对估计矛尾虾虎鱼体长-体重关系参数b的影响。结果表明,增加样本量可有效提高其体长-体重关系参数b的估计精度。不同季节数据对参数估计精度具有不同影响,应用多季节调查采样数据估计参数精度往往优于单季节采样。夏季数据对矛尾虾虎鱼体长-体重关系参数估计尤为重要。方案9(夏-冬季方案)在样本量达到540尾时,相对估计误差REE为2.08%,相对偏差RB的绝对值为0.71%,在相同样本量下该设计方案表现最好。在估计黄河口矛尾虾虎鱼等鱼类体长-体重关系参数时,应保证获得一定样本量的对参数估计具有较大影响的季节的生物学数据。 相似文献
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鱼类体长数据较易获得,常用于数据有限的渔业资源评估和管理,且基于鱼类体长的指标可以作为渔业生态系统的生态监测指标。本文根据山东半岛南部海域底拖网季度调查收集的方氏云鳚体长数据,应用计算机模拟重采样方法,研究了调查站位数对估计方氏云鳚（Enedrias fangi）体长频率分布和平均体长的影响。结果表明,在各个季节,方氏云鳚体长频率分布离散指数（DI）变化范围为0~0.91,大部分站位的DI值为0.75~0.90,说明调查站位间体长频率分布较为相似,可以对调查站位数进行优化,提高采样效率;调查站位越多,体长频率分布和平均体长估计精确度越高;由于对不同体长数据指标估计的精度不同,用以估计体长频率分布和平均体长的样本量存在差异;20个和30个调查站位分别为估计方氏云鳚体长频率分布和平均体长的可接受样本量。本研究结果可为基于不同体长指标的渔业资源调查设计提供一定的理论支撑,有助于对基于体长指标有效站位数的初步了解,为山东半岛南部海域的鱼类资源科学调查和科学管理提供参考。 相似文献
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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
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Time-varying catchability is prevalent in many management regions, and can be modeled using density dependence and time trend parameters. A catchability model can be estimated using single- or multi-species data, and parameter estimates might be of interest as an input for stock assessment models or in their own right (e.g., catchability trends as an index of technology improvements). An operating model was developed to replicate the catch-at-age, fishery-independent survey, and catch-per-unit-effort data from the Gulf of Mexico. Ordinary least squares was used to estimate catchability trends, density dependence, and annual catchability using 10 different estimation procedures. Procedures included an “imputation” strategy, where data from similar species are used to estimate catchability parameters for a focal species. Estimated trend, density dependence, and annual catchability were compared with index-specific operating model values to determine the precision and accuracy of different estimation procedures in a factorial model design. Multi-species procedures increased precision and accuracy of parameter estimates when compared with single-species procedures, and minimized errors in annual catchability estimates when compared with the assumption of constant catchability. Multi-species procedures also did not introduce large errors in functional parameter or annual catchability estimates, even when density dependence and trend were absent or when between-species variability was high. Procedures that imputed catchability functional parameters from similar species were precise and median unbiased given the quantity and quality of data that are available for the Gulf of Mexico. 相似文献
18.
Fishery-dependent catch per unit effort (CPUE) data have been used as an abundance index (AI) in fish stock assessments. However, fishery-dependent CPUE data are influenced not only by changes in fish abundance but also by other factors, such as the choice or restrictions of fishing grounds to operate. Accordingly, bias may arise in AIs due to a lack of data from unfished or rarely fished areas. To improve the accuracy of AI estimates, spatially arranged CPUE datasets from both trawl fisheries and research vessel surveys in the East China Sea were concurrently analyzed in the present study using a multivariate autoregressive state-space (MARSS) model. Survey datasets complemented information on stock status in the fishing areas where fishery-dependent datasets were limited. As a result, the combined use of datasets from both sources effectively improved the accuracy of estimates of AIs and the spatial distribution of the population density of each fish species. 相似文献
19.
Ivy Elizabeth Baremore Kate Irene Andrews Loraine Frances Hale 《Fisheries Research》2009,99(3):203-209
Several methods were used in an attempt to develop an age and growth model for the Atlantic angel shark (Squatina dumeril). Band counts from vertebral sections, which were fit to the traditional von Bertalanffy growth equation, the Gompertz growth equation, and the two-parameter von Bertalanffy growth equation, did not produce realistic parameter estimates. Additionally, a length-based Bayesian model was applied to fishery-independent length–frequency data, and a full Bayesian model was fitted to length-at-age data to estimate parameters for von Bertalanffy growth equation. Both the length-based and full Bayesian models failed to converge; the length–frequency data showed high bimodality unrelated to season, year, or other factors, and band counts were not predictable by length. Vertebral band counts were not valid for ageing Atlantic angel sharks, and length-based methods, which require normally distributed length–frequencies, were not appropriate for this data set. This study represents the first attempt at modeling age and growth for this species and provides research guidelines for future research initiatives. 相似文献
20.
黄河口渔业资源底拖网调查采样断面数对资源量指数估计的影响 总被引：2，自引：2，他引：0
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