赛里木湖新疆高原鳅种群结构研究

20 0 1年 6- 7月在新疆赛里木湖进行了新疆高原鳅种群结构的研究。共测量 32 2 4尾 ,1 7974g ,平均体重 5 6g ,体长波动在 2 1～ 1 6 1cm之间 ,平均体长 9 2cm ,雌雄比为1∶0 7,雌性群体体长、体重组成大于雄性。已经成为赛里木湖种群数量最多的鱼类     

阿克苏河叶尔羌高原鳅Triplophysa(Hedinichthgs)yarkandensis(Day)生物学研究

本对阿克苏河叶尔羌高原鳅的形态特征、群体结构、繁殖、食性等生物学进行了研究。叶尔羌高原鳅体长分布在3．0～15．0cm之间，体重分布在1～33g之间。W=0．039748L^263049.Fulton肥满度雌体平均为1．54，雄体平均为1．46；Clark肥满度雌体平均为1．25，雄体平均1．16。雌体成熟个体最小体长为6．6cm，体重为5．5g，平均绝对怀卵量11543粒／尾。食性以底栖动物、水生昆虫以及鱼类幼体为主。     

塔里木河阿拉尔河段叶尔羌高原鳅群体特征分析

对塔里木河阿拉尔段叶尔羌高原鳅[Triplophysa(Hedinichthys)yarkandensis(Day)]形态特征、体长分布、体重分布、体重与体长的关系以及肥满度进行了初步研究分析。结果表明,塔里木河野生叶尔羌高原鳅体长分布在5.2～22.5cm,体重分布在2.8～128.1g,体重与体长的关系式为W=0.0665L2.3813(r=0.8259),Fulton肥满度平均为1.2583。     

新疆车尔臣河叶尔羌高原鳅繁殖策略

为探究叶尔羌高原鳅(Triplophysa yarkandensis)在车尔臣河的繁殖策略,基于2019—2021年在车尔臣河采集的544尾叶尔羌高原鳅样本,对其繁殖群体组成特征、繁殖期、初次性成熟大小、产卵类型、繁殖力等进行了研究和分析。结果显示,叶尔羌高原鳅的繁殖群体年龄范围为2～9龄,雌雄性比为1.16∶1,属于第二类型(P=K+D,K>D)。观测到的最小初次性成熟体长和年龄为:雌性111.0mm,2龄;雄性79.0mm,2龄;初次性成熟体长(SL50)和年龄(A50)为:雌性123.2mm,3.16龄,雄性90.9mm,2.95龄。根据不同性腺发育时期出现时间和比例、性腺成熟系数和卵径分布推测叶尔羌高原鳅为分批产卵类型,繁殖期为3—8月, 4—6月为繁殖盛期。绝对繁殖力平均为(61407±46143)粒,相对繁殖力平均为(743.87±321.78)粒/g。车尔臣河叶尔羌高原鳅群体相对于其他水域的叶尔羌高原鳅,拥有更大的平均体长、平均体重、初次性成熟体长、较高的绝对繁殖力和较低的相对繁殖力,这是车尔臣河叶尔羌高原鳅群体在食物稀少、生境恶劣且含沙量较大的环境中独特的繁殖策略...     

长江铜陵段紫薄鳅个体生物学与资源保护

按常规生物学方法,对长江铜陵段紫薄鳅（Leptobotia taeniops）的形态特征、体长与体重关系、肥满度、食性、繁殖等个体生物学特征进行了初步研究。结果表明,所取样本体长范围为6.81～12.40cm,体重范围为7.00～36.24g;体长与体重呈显著的幂函数关系：W=0.0348L2.7480（r=0.9090）;为偏动物食性的杂食性鱼类。以体长8.00～10.00cm组的肥满度为高,雄性的Fulton肥满度随体长的逐渐增加而降低。性成熟年龄在1＋～2＋龄,4～7月份产卵繁殖,卵为半漂浮性。种群     

长江铜陵段紫薄鳅个体生物学与资源保护

按常规生物学方法,对长江铜陵段紫薄鳅(Leptobotia taeniops)的形态特征、体长与体重关系、肥满度、食性、繁殖等个体生物学特征进行了初步研究。结果表明,所取样本体长范围为6.81～12.40cm,体重范围为7.00～36.24g;体长与体重呈显著的幂函数关系:W=0.0348L2.7480(r=0.9090);为偏动物食性的杂食性鱼类。以体长8.00～10.00cm组的肥满度为高,雄性的Fulton肥满度随体长的逐渐增加而降低。性成熟年龄在1+～2+龄,4～7月份产卵繁殖,卵为半漂浮性。种群性比为1:1.4,V期绝对怀卵量平均为2602粒,相对怀卵量平均为127粒/g,成熟卵的卵径达(1.47±0.10)mm。年龄分为3个组,其中2+龄个体占63.79%。     

塔里木河阿拉尔段叶尔羌高原鳅群体特征分析

对塔里木河阿拉尔段叶尔羌高原鳅[Triplophysa（Hedinichthys）yarkandensis（Day）]形态特征、体长分布、体重分布、体重与体长的关系以及肥满度进行了初步研究分析。结果表明,塔里木河野生叶尔羌高原鳅体长分布在5.2～22.5cm,体重分布在2.8～128.1g,体重与体长的关系式为W=0.0665L2.3813（r=0.8259）,Fulton肥满度平均为1.2583。     

阿克苏河长身高原鳅Triplophysa (Triplophysa) teunis (Day)生物学研究

本文对2004年3—10月份采集的阿克苏河长身高原鳅的形态特征,生活习性,群体结构,繁殖特点,食性等生物学进行了初步的研究。长身高原鳅体长分布在3．4—12．1cm之间,体重分布在0．31—13．7g之间。W=0．0090293L^2.9666（r=0．970）。Fulton肥满度雌体平均为0．88,雄体平均为0．86;Clark肥满度雌体平均为0．61,雄体平均为0．64。雌体成熟个体最小体长为5．4cm。体重为1．4g。平均怀卵量2451粒／尾。食性以底栖动物,昆虫幼体等动物性饵料为主,其次是植物碎片和有机碎屑。     

塔里木河干流叶尔羌高原鳅种群生物学研究

2009年对塔里木河干流叶尔羌高原鳅[Triyplophysa(Hedinichthys)yarkandensis(Day)]群体生物学进行研究。叶尔羌高原鳅体长、体重相关方程为:W=0.0190L2.8911;相对怀卵量平均为(1160.7±364.7)粒/g,性腺处于Ⅳ期发育阶段的雌、雄鱼平均成熟系数分别为(13.59±5.21)%、(0.79±0.26)%;集中产卵时间在6-7月份,繁殖水温约为22℃。食物组成以水生高等植物(秋季)和水生昆虫(春季)为主,秋季的摄食率、饱满度及摄食强度等指标远高于春季。春季群体,体长5~8cm、体重4.1~8.1g,主要为繁殖群体;秋季群体,体长2~5cm、体重0.1~4.1g,主要为育肥生长阶段的幼小群体。当干流全线有一定流量或有洪水暴发时,叶尔羌高原鳅遍布于塔里木河干流全线,并在干流鱼类种群数量中占优势地位,其种群资源主要集中在塔里木河干流阿拉尔河段;该鱼属于广温性(0.2~33℃)底层小型鱼,具有耐低氧、喜集群及短距洄游特性。     

西溪高原鳅生物学研究

对91尾西溪高原鳅的生物学进行了初步研究。体长范围为4．8～12．9cm，体重范围为1．59～26．92g；体长与耳石大小呈显著的线性相关；体重与体长呈显著的幂函数关系；年龄可分为4个龄组，以2龄和3龄个体占绝大多数。脊椎骨是鉴定西溪高原鳅年龄的理想材料，而耳石不适合于年龄鉴定。     

达里湖东北雅罗鱼的生长、死亡和生活史类型的研究

达里湖东北雅罗鱼(Leucisus waleckii)的种群结构参数(体长、体重和年龄)进行测定,估算种群的生长和死亡参数,并研究种群的生活史类型。结果显示:东北雅罗鱼的体长和体重的关系式Wt=0.0281L2t.8152,其vonBertalanffy生长方程各参数为渐近体长L∞=28.9763 cm,渐近体重W∞=366.95 g,生长系数k=0.2586,t0=-0.3237;自然死亡系数M为0.322,总死亡系数Z为0.9386,捕捞死亡系数F为0.6166;生活类型为r-选择。结果表明:作为渔业管理对策,达里湖东北雅罗鱼的起捕年龄应定为3龄以上。     

Status of the fishery of Pimbmrettewa wewa, a man-made lake in Sri Lanka

Abstract. The status of the fishery of Pimburctlewa wewu, a man-made lake in Sri Lanka, was studied from January 1985 to January 1986. The annual fish yield in the reservoir is 441 kg/ha, one of the highest in the south-east Asian region. Oreochromis mossambicus (Peters) is the dominant species in the fishery and accounted for about 90% by weight of the total catch. Although there were monthly variations in catch per unit effort, the daily catch per fisherman was not adversely affected. A possibility of having a more productive fishery is suggested In reducing The minimum permissible mesh size in the gillnet fishery during the peak recruitment season in May–June. The possible effects of reducing the mush size are discussed. Using the length-frequency data of O. mossambicus , the asymptotic length and the growth constant were estimated to be 39.3cm and 0.34 respectively. The estimates of total mortality (2.42). natural mortality (0–82) and mean selection length (24.6 cm) were based on these growth parameters Yield-per-recruit analysis indicated that the O. mossambictus fishery in the reservoir was optimally exploited.     

黄金鲈♀×伊犁鲈♂杂交代的形态特征与人工养殖技术

对黄金鲈♀×伊犁鲈♂杂交后代的形态特征与黄金鲈和伊犁鲈进行了比较,并就其人工养殖技术进行了探讨。结果表明:2龄杂交鲈体长26.5～31.5cm,(L=28.53±1.69cm),体重339.0～650.5g,(=447.31±94.23g)。体长为体高的3.58～3.93倍,两背鳍分离,第一背鳍棘14～16根,体侧扁,长椭圆形,形态特征与黄金鲈相似,体背为灰绿色,颜色介于黄金鲈与伊犁鲈之间,身体两侧有5～9条黑色横斑,属于温、冷水性鱼类,生长的最适温度为22～25℃,室内养殖条件下,投喂颗粒饵料,并辅以动物性饵料,生长迅速,日均增重率可达0.62g/d。     

东海区黄(鱼安)(鱼康)资源状况的初步探讨

本文以 2 0 0 2年东海区渔业资源监测调查资料为依据 ,研究分析了黄的洄游分布、渔业生物学特征和资源量状况。结果表明 ,东海区黄主要分布在黄海南部和东海北部海域 ,高资源密度主要分布在水深 4 0～ 10 0m海域 ,但各调查月份有差异 ;9月份黄个体平均体长为 2 15 .35mm ,优势体长组为 14 0～180mm ,占 5 3% ;平均体重为 397.83g ,优势体重组为 70～ 14 0g ,占 4 5 % ;现存资源量评估结果为 2 0 15t,但实际资源量估计约在 1× 10 4t以上 ,属于有潜在价值渔业。     

Changes in the fish and fisheries ecology of a large man-made lake in Tanzania, 1965–94

Abstract Nyumba ya Mungu Reservoir in northern Tanzania has a maximum surface area of 180 km², an average depth of 6 m, and contains moderately saline, fertile water. The postimpoundment decade, 1965–74, was characterised by a spectacular rise and fall of a tilapiabased fishery. Since then a gill-net fishery catching large numbers of large, periphyton-grazing tilapias has given way to a mainly beach-seine fishery producing large numbers of small, phytoplankton-feeding Oreochromis esculentus (Graham). Yields remain higher than preimpoundment predictions but the size at maturity of all tilapia species has fallen and few larger than 15 cm TL are caught. These changes, and others in the fish community trophic structure, are chiefly explained by changes in the littoral environment and fishing pressures. Nyumba ya Mungu provides a case history of developments in the tilapia fishery of a man-made river lake conducted on an essentially laissez-faire basis.     

涨渡湖渔业资源及鱼类多样性状况研究

武汉市新洲区涨渡湖渔业生产是以人工投放、天然生长为主,鱼类资源自然增殖为辅的粗放型管理模式进行。1992~2004年捕捞产量变幅范围为(3.69~50.61)×104kg,其中有9个年份变幅在10×104kg以上;产品收入变幅范围为(2.77~201.77)×104元,其中有6个年份变幅在50×104元以上。目前涨渡湖鱼类共有47种,与历史最高种数比较,下降了38.2%。渔获物组成中,放养鱼类占80%以上,人工放养是目前涨渡湖鱼类补充群体的主要来源;鱼类年龄结构简单,主要经济鱼类低龄化趋势严重;主要品种鲢、鳙的生长速度慢于同类湖泊。江湖隔绝和长期的人工增养殖生产作业方式,是导致涨渡湖鱼类区系逐渐简单化,鱼类多样性下降的重要原因。     

黑龙江绥滨江段鲢鱼渔业生物学研究

2001年春汛期对黑龙江中游绥滨江段鲢鱼三层流刺网捕捞群体生态学特征进行研究。捕捞群体由体长47-74.5cm组成，平均为61.08cm；体重由1700-7000g组成，平均为3574.3g组成，年龄3^ - 8^ 龄组成，以4龄为主，占26.2%；绝对生殖力由318500-763125粒组成，平均为445593粒；相对生殖力81.66-231.25粒/g，平均为143.12粒/g；成熟系数雌群平均为18.68%(12.82-28.03)，雄群平均为2.12%(1.09-3.35)；肥满度雌群平均为0.0135%(0.0121-0.0146)，雄群平均为0.0140%(0.0128-0.0149)；种群数量点51.4%，重量占70.8%，共计7.8t，计2078尾。调查结果表明黑龙江绥滨江段鲢鱼资源呈下降趋势。     

Autecology of chub, Leudscus cephalus (L.), in a Greek stream, and the use of the pharyngeal bone in fish predator-prey studies

Abstract. The autccology of chub, Leudscus cephalus (L.), in the Renlina Stream, Greece, was carried out in an effort to obtain information on the age, growth, mortality and reproduction of this species. Fork length increment during the first year of life was 8·9cm, after which it decreased. Life span was short (maximum age 8 years) and the instantaneous mortality rates were higher for the older age-groups. Chub reached sexual maturity at the second year of life for both sexes and spawning occurred from the second fortnight of April into May, at a mean water temperature of 18°C. The relationship between fecundity ( F ) and fork length (1) was F = 0·0797 L^3·63 The average density and biomass were 1·06 fish.m⁻² and 11·38g.m⁻² respectively. The relationship between L and the pharyngeal bone size [gape ( G ), tip ( T ) and shank ( S )] in mm and caudal fin length ( C ) (cm) can be described by the equations: L = 0·8605 + 1·550 G , L = -0·0703 + 1·332 S, L = 1·092 + 1·615 T and L = 1·032 + 2·934 C .     

青海湖裸鲤种群数量变动的初步分析

青海湖裸鲤是青海湖唯一的捕捞对象。开发后的种群数量变动主要根据1975-1977年该湖渔获物资料及过去研究的裸鲤生物学特性。计算了该种群的若干特征值，应用BevertonHolt数学模式计算不同捕捞努力量或用不同网目的拖网对裸鲤种群在一生中总个体数、总生物量，和对裸鲤种群一生中能捕捞的总个体数及总渔获重量的影响，以及裸鲤的最大持续产量和现有种群数量。评价了裸鲤资源利用现状，提出有关生产的一些初步意见。     

Checking the pulse of the major commercial fisheries of lake Victoria Kenya,for sustainable management

The present study demonstrates the declining state of the major commercial fisheries of Lake Victoria, Kenya, a situation threatening sustainability of the lake's fishery. Data in the present study were derived from resource monitoring programmes that included hydro‐acoustics (2009–2018), trawl net fishing (2011–2018), frame surveys (2000–2016) and catch assessment surveys (2000–2015). The activities provided information on fish stocks and supported advice for fisheries management. The average fish stock densities for Tanzania, Uganda and Kenya of 8.92, 8.25 and 8.19 t/km², respectively, were relatively similar. Diplomatic and sustainable efforts for harmony in fish harvesting among the fishers of the riparian countries are encouraged given the interdependence of the lake. The Kenyan and River Kagera regions had a higher proportion (≈ 4% each) of big‐sized Nile perch (≥50 cm total length) in 2018, signifying the critical breeding areas for Nile perch. To sustain the fishery, there is need to enforce a 36%–44% effort reduction for all the major fisheries, and enforcement of gear limits to avoid harvesting of immature fish and destruction of the lake ecosystem.