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1.
智利外海茎柔鱼生物学特性的初步研究 总被引：2，自引：0，他引：2
根据2007年1月和5～6月我国鱿钓船在智利外海的调查数据,对茎柔鱼生物学特性进行初步分析。结果表明:该地区茎柔鱼胴长范围287～702 mm,优势胴长为380～430 mm,占64.2%;体重范围0.63～11.3 kg,优势体重为0.5～2.0 kg,占75.6%;调查海区渔获个体自西向东、自南往北呈现增大趋势;依据胴长组成推断调查海域可能存在3个群体。生长指数大于3,与秘鲁外海茎柔鱼相近;雌雄性比约为3:1,性腺成熟度以Ⅰ期为主,占92%;摄食等级0～2级为主,约占73%;当地时间00:00后摄食量增大,胃含物以鱿鱼和中上层小型鱼类为主。 相似文献
2.
水温变动对2009年西北太平洋柔鱼产量下降的影响 总被引：1，自引：0，他引：1
分布在西北太平洋的柔鱼是我国远洋鱿钓渔业的重要捕捞对象,近些年来其产量一直处在稳定的水平。然而,2009年8～10月旺汛期间在传统作业渔场(150°E～165°E、38°E～46°E)柔鱼产量出现大幅度下降,其日产量仅为正常年份的一半。为此,根据2007～2009年8～10月我国在西北太平洋鱿钓生产数据,以及产卵场表层水温,探讨2009年柔鱼产量下降及渔场变动的原因。研究表明,其产量出现下降的原因可能有2个:(1)柔鱼产卵场(20°N～30°N,130°E～170°E)黑潮大弯曲的发生,使得21℃等温线向南偏移,使得柔鱼资源补充量受到影响,从而使得渔汛期间柔鱼产量的下降;(2)旺汛期间(8～9月)传统作业渔场(42°N～46°N,150°E～165°E)的100m水层有一个明显冷水南下,分布位置为154°E～156°E,将传统作业渔场(150E～165°E)一分为二,向南的前锋(水温低于5℃)到达42°N,明显不同于正常年份,使得作业渔场的范围明显缩小,不适合柔鱼的集群,导致产量出现大幅下降。 相似文献
3.
东太平洋赤道公海茎柔鱼生物学特性 总被引：1，自引：0，他引：1
根据2013年4~6月在赤道公海探捕期间采集茎柔鱼样本,研究赤道公海茎柔鱼渔业生物学特性。结果表明,不同性别、不同月份,茎柔鱼胴长和体质量组成不同。雌、雄性样本的胴长范围分别为93~495 mm和94~406 mm,优势胴长组分别为260~340 mm和240~320 mm,分别占样本总数72.53%和70.26%;雌、雄性样本体质量范围分别为25~3 900 g和33~2170 g,优势体质量组分别为400~1 200 g和200~1 000 g,分别占样本总数82.71%和87.82%。雌、雄性茎柔鱼净体质量比例分别介于31.69%~80.51%和37.05%~81.35%之间,平均值分别为60.45%和62.73%。协方差分析表明,茎柔鱼胴长与体质量、胴长与净体质量的生长均存在性别间差异,胴长与体质量的生长都最适合用幂函数表示,而胴长与净体质量的生长,雌、雄性样本分别最适合用幂函数和指数函数表示。不同月份茎柔鱼性别比例构成不同,4月、5月和6月性别比例分别为1.87∶1、1.61∶1和1.17∶1,全部样本的性别比例为1.61∶1。不同月份茎柔鱼性腺成熟度的组成不同。不同性别、不同月份间茎柔鱼胃含物等级组成存在差异。 相似文献
4.
<正>茎柔鱼(Dosidicus gigas)是头足类中个体最大、资源最丰富的种类之一[1],广泛分布于东太平洋的加利福尼亚(37°N)到智利(47°S)的海域中,在赤道附近可向西至125°W[1-4],有学者认为其分布范围在赤道附近可达到140°W[5]。20世纪90年 相似文献
5.
根据2000年中国鱿钓船在西南大西洋的生产统计和表温资料,按经纬度1°×1°进行统计,并用渔业地理信息软件MarineExplorer4 .0进行叠加分析。结果表明, 1~5月阿根廷滑柔鱼分布中心集中在45°S、60°W附近海域。各月产量和平均日产量有较大的变动,其中以2~3月为最高。1~5月作业渔场的适宜表温范围为7~14℃,并经过K S检验。但各月的适宜表温有所不同, 2月为11 ~12℃, 3月为10 ~12℃, 4月为8 ~9℃, 5月为7 ~8℃。在表温比往年稍偏高的作业海域,有利于渔场的形成和产量提高。 相似文献
6.
对 2 0 0 0年 5～ 7月北太平洋中东部海域鱿钓探捕调查所获的不同深度海水温度和柔鱼渔获量等资料进行分析 ,结果表明在西经调查水域的 1 74°W和 1 71°W附近 ,1 0 0m ,2 0 0m和 3 0 0m水温分布均形成明显的暖水舌 ,其特征水温依次为 1 0～ 1 1℃ ,9～ 1 0°C及 8～ 9°C ;在东经调查水域 ,表层以下各层水温较往年有所偏低 1～ 2度。分析结果还表明 ,西经调查水域的中心渔场均处在暖水舌前锋一侧 ,中心渔场形成的水温指标为 :表层 1 3～ 1 4°C ,1 0 0m水层 1 0～ 1 1°C、2 0 0m水层 9～ 1 0°C及 3 0 0m水层 8～ 9°C ;在东经调查水域 ,调查期间没有形成中心渔场 ,这可能与深层水温偏低有关 相似文献
7.
【目的】了解我国近海短蛸(Octopus ocellatus)的生物学特性,比较不同海域短蛸的差异。【方法】根据2015年10～11月在东海和黄海采集的272尾短蛸样本,研究其胴长和体质量组成、性别比例、性腺成熟度和摄食强度等生物学特性。【结果】东海芦潮港海域短蛸的胴长范围为38～75mm,平均胴长为53.6mm,优势胴长组为50～70 mm;体质量范围为24～92 g,平均体质量为56.7 g,优势体质量组为50～90 g;东海舟山海域短蛸的胴长范围为30～75 mm,平均胴长为56.0 mm,优势胴长组为45～70 mm;体质量范围为27～123 g,平均体质量为68.9 g,优势体质量组为60～100 g;黄海青岛海域短蛸的胴长范围为36～90 mm,平均胴长为65.6 mm,优势胴长组为55～70 mm;体质量范围为23～276 g,平均体质量为111.2 g,优势体质量组为60～140 g。不同海域的短蛸性比不同,黄海短蛸雌性多于雄性,东海雄性多于雌性。【结论】不同海域的短蛸在胴长、体质量、性比、性成熟度等方面存在差异。 相似文献
8.
多变量分位数回归构建印度洋大眼金枪鱼栖息地指数 总被引：1，自引：0，他引：1
以0～300m水层加权平均水温、50～150m水层的温差和氧差及其交互变量为影响因子,运用分位数回归法,寻找出环境变量与大眼金枪鱼(Thunnus obesus)延绳钓钓获率的最佳上界分位数回归方程,计算出栖息地指数(HSI),并应用地理信息系统(GIS)软件绘制各月HSI空间分布图。研究表明:大眼金枪鱼延绳钓钓获率(HR)依加权平均水温(x)、温差(y)、氧差(z)与的最佳上界分位数回归方程为HR0.70=-15.596+2.124x-0.003x3+0.033xyz-0.036y2z+0.107yz2-0.337z3;HSI空间分布为:16°S—10°N印度洋海域HSI高于0.7,HSI>0.8的海域随季节发生显著变化,马达加斯加外海至100°E、16°S—26°S海域常年存在一片HSI<0.4的区域,26°S—40°S海域的HSI介于0.4～0.5,40°S以南海域HSI<0.4,东非外海季节性地出现一片HSI<0.6的海域。利用多个环境变量的栖息地指数模型来预测分析大洋金枪鱼资源分布效果较好。 相似文献
9.
《广东海洋大学学报》2015,(6)
根据日本对太平洋褶柔鱼秋生群体的资源评估报告,以及产卵场海表温度(tSST)、叶绿素a质量浓度(ρChl-a),计算分析太平洋褶柔鱼在产卵期产卵场各月最适表温范围占总面积的比例(PS)、表征产卵场环境的tSST、ρChl-a等多种环境因子与单位捕捞努力量的渔获量(CPUE)的相关性,建立多种基于主要环境因子的资源补充量预报模型。结果表明:太平洋褶柔鱼资源补充量与各月的tSST的相关系数最大值海域分别为10月份的Point1(33.5°N,129.5°E)、11月份的Point2(31°N,127°E)和12月份的Point3(33.5°N,125°E);与各月的ρChl-a浓度的相关系数最大值海域出现在11月份的Point4(34°N,129.5°E)和12月份的Point5(35°N,130°E)。基于Point1的tSST、Point4的ρChl-a、PS等3个因子作为输入层构建的3-2-1的BP网络结构,2011-2012年的平均预报精度达到最高,为91.5%,该模型可用于太平洋褶柔鱼资源补充量的预测。 相似文献
10.
西北太平洋柔鱼资源与海洋环境的GIS空间分析 总被引：12，自引：0，他引：12
本文根据1995～2001年的西北太平洋地区(35°N～45°N,140°E～170°W)巴特柔鱼资源调查与生产的实际情况对柔鱼渔获量进行了研究,并利用同期遥感反演的海洋表层温度数据(SST)和近表层叶绿素a数据(Chlorophylla),拓展了GIS的空间分析功能,定量地研究了我国远洋柔鱼产量与水温、叶绿素等海洋要素场之间的关系,揭示西北太平洋柔鱼中心渔场的环境特征,以期为我国西北太平洋海区的鱿鱼生产服务。 相似文献
11.
Study of the distribution and migration of the common squid,Todarodes pacificus Steenstrup,basedon the index of important fishing ground(P) and fisheries statistics on the Yellow Sea and northern EastChina Sea during 1980—1991 showed that:1.Its catch in the fishing period(June to November) is 91.77% of the annual yield.The fishingground distributes over the northem and middle Yel1ow Sea and adjacent area of the Changjiang Estuary.2. It over-winters in the northem East China Sea and waters adjacent to Goto Island from De-cember to February and spawns in waters near Haijiao Is1and and west of Kyushu. The main stock mi-grates along 123°30′E to the ChangJiang Estuary, Haizhou Bay. offsea from Shidao to Qingdao,mideastern Yellow Sea, and offsea Weihai and Haiyang Island succesively for feeding after April. The sur-plus stock migrates again to the wintering ground in December.3.The favorable feeding temperature is 6-23℃(optimum of l3-20℃ in the Changjiang Estua-ry and 7-13℃ in the northern and middle Yel 相似文献
12.
智利外海茎柔鱼耳石生长特性的性别差异研究 总被引：1，自引：0，他引：1
根据2007年1~6月和2008年1~5月我国鱿钓船在智利外海调查期间采集的茎柔鱼耳石样本,测量了503枚耳石外部形态参数(雌性348枚,雄性155枚),结合耳石日轮,对耳石生长特性的性别差异进行了研究.结果表明,耳石总长(TSL)、耳石半径(SR)、吻侧区长(RLL)、翼长(WL)及最大宽度(MW)可作为茎柔鱼耳石形态的表征参数.雌雄个体间耳石的生长在5个形态参数上均存在显著性差异,雌性个体 TSL 与日龄间关系最适为指数函数, SR 和 RLL 为幂函数, MW 和 WL 则为线性函数;雄性个体的 TSL、SR 和 RLL 与日龄间的关系最适为幂函数, MW 和 WL 为线性函数.雌性个体 TSL、SR、MW、RLL、WL 的相对生长率和SR、RLL 绝对生长率均随着日龄的增加而先增加后减小, TSL、MW 绝对生长率随着日龄的增加而增加,WL绝对生长率则随着日龄增加而呈现波动趋势;雄性个体 TSL、SR 相对生长率和 MW、RLL、WL 绝对生长率随着日龄增加先增加后减小,而 MW、RLL 和 WL 相对生长率和 TSL、SR 绝对生长率则随日龄增加呈现波动趋势.研究认为,茎柔鱼耳石生长存在性别差异,通常雌性生长较雄性快 相似文献
13.
Based on the biological data of purpleback flying squid(Sthenoteuthis oualaniensis)collected by light falling-net in the southern South China Sea(SCS) during September to October 2012 and March to April 2013,growth and mortality of 'Medium' and 'Dwarf' forms of squid are derived using the Powell-Wetherall,ELEFAN methods and length-converted catch curves(FiSAT package).Given a lack of commercial exploitation,we assume total mortality to be due entirely to natural mortality.We estimate these squid have fast growth,with growth coefficients(k) ranging from 1.42 to 2.39,and high natural mortality(M),with estimates ranging from 1.61 to 2.92.To sustainably exploit these squid stocks,yield per recruitment based on growth and natural mortality was determined using the Beverton-Holt dynamic pool model.We demonstrate squid stocks could sustain high fishing mortality and low ages at first capture,with an optimal fishing mortality 3.0,with the optimal age at first capture increased to 0.4-0.6 years when fishing mortality approached optimal levels.On the basis of our analyses and estimates of stock biomass,we believe considerable potential exists to expand the squid fishery into the open SCS,relieving fishing pressure on coastal waters. 相似文献
14.
The relationships between the neon flying squid, Ommastrephes bartrami, and the relative ocean environmental factors are analyzed. The environmental factors collected are sea surface temperature (SST), chlorophyll concentration (Chl-a) and sea surface height (SSH) from NASA, as well as the yields of neon flying squid in the North Pacific Ocean. The results show that the favorable temperature for neon flying squid living is 10℃-22℃ and the favorite temperature is between 15℃-17℃. The Chl-a concentration is 0.1-0.6 mg/m3. When Chl-a concentration changes to 0.12-0.14 mg/m3, the probability of forming fishing ground becomes very high. In most fishing grounds,the SSH is higher than the mean SSH. The generalized additive model (GAM) was applied to analyze the correlations between neon flying squid and ocean environmental factors. Every year, squids migrate northward from June to August and return southward during October-November, and the characteristics of the both migrations are very different. When squids migrate to the north, most relationships between the yields and SST are positive. The relationships are negative when squids move to southward. The relationships between the yields and Chl-a concentrations are negative from June to October, and insignificant in November. There is no obvious correlation between the catches of squid and longitude, but good with latitude. 相似文献
15.
Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008–2010. Estimated ages ranged from 144 to 633 days, confirming that the squid is a short-lived species with longevity no longer than 2 years. Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round. Back-calculated hatching dates for the samples were from January 22nd, 2008 to April 22nd, 2010 with a peak between January and March. Two size-based and two hatching date-based populations could be defined from mantle length (ML) at maturity and back-calculated hatching dates, respectively. Females matured at a larger size than males, and there was a significant difference in ML at maturity between the two hatching groups (P <0.05). The waters adjacent to 11°S off the Peruvian EEZ may be a potential spawning ground. This study shows the complexity of the population structure and large variability in key life history parameters in the Humboldt squid off the Peruvian EEZ, which should be considered in the assessment and management of this important resource. 相似文献
16.
《中国海洋湖沼学报》2021,(3)
Identification of squids in the family Loliginidae is a time-consuming exercise because of the highly overlapping distributions of species and their overall similarity(fin shape and size, sucker ring dentition, and color). Identifying squid based on statolith morphology is considered more accurate than identifying species based on beaks or gladius morphology. We report and compare the statolith shape offive commercially Loliginidae squid( Uroteuthis( Photololigo) duvaucelii, U. edulis, U. chinensis, Loliolus beka, L. japonica) to determine how well these structures discriminate species. Based on statolith morphology, variation in the lateral and dorsal domes enables an 84.8% success rate at classifying species. Environmental factors correlate with statolith shape, and for vertically migrating squid, statolith relative size decreases with increased depth of habitation. Statolith morphology can be used to effectively and accurately identify species of Loliginidae squid occurring in Chinese waters, and may prove valuable for identifying and managing squid resources. 相似文献
17.
The impact of spatial autocorrelation on CPUE standardization between two different fisheries 总被引：2，自引：0，他引：2
Catch per unit of eff ort(CPUE) data can display spatial autocorrelation. However, most of the CPUE standardization methods developed so far assumes independency of observations for the dependent variable, which is often invalid. In this study, we collected data of two fisheries, squid jigging fishery and mackerel trawl fishery. We used standard generalized linear model(GLM) and spatial GLMs to compare the impact of spatial autocorrelation on CPUE standardization for different fisheries. We found that spatialGLMs perform better than standard-GLM for both fisheries. The overestimation of precision of CPUE estimates was observed in both fisheries. Moran's I was used to quantify the level of autocorrelation for the two fisheries. The results show that autocorrelation in mackerel trawl fishery was much stronger than that in squid jigging fishery. According to the results of this paper, we highly recommend to account for spatial autocorrelation when using GLM to standardize CPUE data derived from commercial fisheries. 相似文献
18.
A comparison of fishery biology of jumbo flying squid, Dosidicus gigas outside three Exclusive Economic Zones in the Eastern Pacific Ocean 总被引：1，自引：0，他引：1
Although many studies on the fishery biology of jumbo flying squid, Dosidicus gigas, have been conducted in the coastal areas within Exclusive Economic Zones (EEZs) of various countries due to its commercial and ecological importance, limited biological information is available from waters outside these EEZs. In this paper, we examined D. gigas fishery biology from waters outside Chilean, Peruvian and Costa Rican EEZs, based on the fishery data collected by Chinese jigging vessels during 2006 to 2010. The dominant mantle lengths of D. gigas were 350–450 mm, 250–400 mm and 250–350 mm outside Chilean, Peruvian and Costa Rican EEZs, respectively. Size structure analysis show that a medium-sized group existed mostly in the waters outside the Chilean and Peruvian EEZs, whereas a small-sized group occurred mainly in the waters outside the Costa Rican EEZ. The longevity of the squid outside the Costa Rican EEZ was less than 10 months, while most of those outside Chilean and Peruvian EEZs were about 1–1.5 years and very few large individuals were 1.5–2 years old. A higher percentage of mature individuals existed outside Costa Rican EEZ implying the region as a potential spawning ground, while lower proportions of mature squid outside the Peruvian and Chilean EEZs indicated that spawning may be occurring outside our study area. Spatial differences in sizes at maturity of the squid are thought to be result from different environmental factors especially different temperature and nutrition among the three areas. Stomach-content analysis showed that cannibalism was important in the diet of D. gigas. Stress generated by jigging may increase the incidence of cannibalism. 相似文献