漠斑牙鲆内陆淡水池塘网箱养殖试验

通过内陆淡水池塘网箱养殖漠斑牙鲆试验,探索出内陆淡水池塘漠斑牙鲆网箱养殖的模式,总结出养殖过程中应采取的技术措施,25m2网箱总产漠斑牙鲆102.9kg,平均单产4.12kg/m2,漠斑牙鲆平均规格为306.25g/尾,成活率达84%,使池塘产量比往年养殖产量增加5.94%。     

盐碱地低盐水池塘网箱套养漠斑牙鲆技术研究

根据漠斑牙鲆(Paralichthys lethostigma)适广温、广盐和较强的抗逆性等优良生态习性,采用地下卤水、盐碱地渗水,通过合理淡水配兑使其适合漠斑牙鲆生理生长需求,在我国中纬度地区利用盐碱地低盐水养殖过洋、暖温性漠斑牙鲆。2004-2005年,利用盐碱地低盐水池塘虾池设置网箱套养漠斑牙鲆349.5m2,产鱼3.749t,产虾55.065t,其中2005年虾池设置网箱套养漠斑牙鲆306m2,产鱼3.245t,平均10.6kg/m2,平均全长34.0cm,体重527.4g,养殖成活率为90.5%,产虾49.003t,平均408.4kg/亩,平均规格11.9cm,养殖成活率为71.23%。虾池设置网箱套养漠斑牙鲆,可充分利用水体空间,促使池塘高产高效,提高养殖经济效益。     

低盐水池塘网箱套养漠斑牙鲆试验

根据漠斑牙鲆适广温、广盐和高度的抗逆性等优良生态习性，使其在黄河三角洲地域养殖成功成为可能；采用地下卤水、盐碱地渗水，通过合理配兑淡水使其适合漠斑牙鲆生理生长需求，在我国中纬度地区利用盐碱地低盐水养殖过洋、暖温性漠斑牙鲆获得成功。2004—2005年，利用盐碱地低盐水池塘，虾池设置网箱套养漠斑牙鲆349．5m^2，产鱼3．749t．产虾55．065t．其中2005年虾池设置网箱套养漠斑牙鲆306m^2。产鱼3．245t，平均10．6kg／m^2，平均全长34．0cm，体重527．4g，养殖成活率为90．5％，产虾49．003t，平均6126kg／hm^2，平均规格11．9cm，养殖成活率为71．23％。虾池设置网箱套养漠斑牙鲆，可充分利用水体空间。促使池塘高产高效，提高养殖经济效益。该成果在盐碱地域同类研究中处国际先进水平。     

漠斑牙鲆微咸水养殖试验

在盐度为2.0～3.0的微咸水条件下,用已淡化的漠斑牙鲆鱼种开展漠斑牙鲆工厂化养殖试验。经183d养殖,漠斑牙鲆平均体重由45g增长至313g,平均增重268g,日均增重1.46g,成活率92.9%,平均产量7.21kg/m2,投饲系数0.73。     

漠斑牙鲆淡化养殖死亡原因分析

笔者在漠斑牙鲆淡水养殖过程中发现其后期死亡率偏高,治疗效果不太明显,因此将养殖情况作此总结和简要分析,希望能为广大养殖者提供参考。一、漠斑牙鲆淡化养殖死亡情况及防治过程2004年4月从山东引进盐度为30的漠斑牙鲆鱼种1500尾,平均体长15.8厘米,平均体重45克/尾。引进后经     

“漠斑牙鲆子二代苗种繁育与养殖技术研究”通过鉴定

日前，由莱州市大华水产有限公司进行的“漠斑牙鲆子二代苗种繁育与养殖技术研究”通过了省科技厅组织的专家鉴定。该公司在2002年以来进行漠斑牙鲆引进与苗种规模化生产研究和漠斑牙鲆养殖研究的基础上，于2004年以来开展漠斑牙鲆子二代苗种繁育与养殖技术研究，通过4年多的试验研究和生产实践，建立了漠斑牙鲆子二代苗种人工繁育、养殖工艺技术和养殖模式，实现了亲鱼自然产卵，验证了漠斑牙鲆适合于池塘养殖、工厂化养殖和网箱养殖。共培育出性状优良的漠斑牙鲆子一代亲鱼200尾，繁育子二代苗种94．3万尾，延续了子一代鱼的优良性状。试验养殖，池塘养殖成活率达到90％，每667m^2产量达到276．8kg；工厂化养殖成活率达到95％，单产达到每平方米11．7kg；网箱养殖成活率达到86．9％，单产达到每平方米10．4kg。养殖效益显著。     

盐碱地低盐水池塘网箱套养漠斑牙鲆技术

2004-2005年,利用盐碱地低盐水虾池设置网箱套养漠斑牙鲆349.5m2,产鱼3.749t,产虾55.065t,其中2005年虾池设置网箱套养漠斑牙鲆306m2,产鱼3.245t,平均10.6kg/m2,平均全长34.0cm体重527.4g,养殖成活率为90.5%,产虾49.003t,平均408.4kg/667m2,平均规格11.9cm养殖成活率为71.23%。     

淡水闭合循环养殖条件下养殖密度和个体大小对漠斑牙鲆(Paralichthys lethostigma)幼鱼生长的影响

以新疆伊犁河生态渔业中心漠斑牙鲆循环水养殖系统为实验平台，在生产规模上研究了闭合循环淡水养殖条件下养殖密度和个体大小对漠斑牙鲆幼鱼生长的影响。结果表明：漠斑牙鲆池底覆盖率低于34％时，养殖密度对漠斑牙鲆生长的影响不显著（P〉0．05）；养殖密度对个体大小的分化具有显著影响（P〈0．05），加强养殖管理可以降低该影响；漠斑牙鲆全长120mm时，性别分化基本完成，雄鱼规格和生长速度明显低于雌鱼。     

池塘网箱漠斑牙鲆套养项目通过专家鉴定

近日,由河口区海洋与渔业局承担的《半咸水南美白对虾养殖池塘高效综合利用———网箱漠斑牙鲆养殖技术试验》科研项目,通过专家鉴定,该项目综合研究达到国内领先水平。项目实施两年,共开发推广南美白对虾与漠斑牙鲆套养面积250亩,漠斑牙鲆养殖网箱(3m×3m)100个,鱼虾总产84.3t,漠斑牙鲆网箱平均单产11.2kg/m2,实现产值379.6万元,效益215.7万元,辐射带动养殖面积1 000亩,实现产值1 500万元,经济和社会效益显著。项目根据黄河三角洲地区荒碱地资源优势和养殖现状,首次在国内利用半咸水南美白对虾养殖池塘进行网箱漠斑牙鲆养殖,取得成功,并总…     

漠斑牙鲆养殖研究的进展

漠斑牙鲆肉质细腻,味道鲜美,幼鱼经驯化后可在淡水中生长。这些特点使养殖经营者对它十分关注,尤其是在美国。自1997年第一篇研究漠斑牙鲆催产方法的论文问世以来,有关漠斑牙鲆养殖的研究越来越多,但目前离大规模生产还有一定距离。为了引起国内养殖业界对漠斑牙鲆养殖研究的关注,本文报道了漠斑牙鲆人工养殖方面的研究成果,以飨读者。     

池塘主养彭泽鲫鱼种高产试验报告

池塘面积1067m^3，主养彭泽鲫鱼种，搭配团头鲂及鲢鳙鱼种，经156天饲养，共产鱼1029．6kg，折合667m^2产鱼643．5kg。其中每667m^2产彭泽鲫鱼种367．8kg,平均规格70g。每667m^2利润3498元。投入产出比为1：1．67。     

Evaluation of observer‐ and industry‐based catch data in a recreational charter fishery

There is international recognition for greater inclusion of recreational fisheries catch data in species, fisheries and ecosystem assessments. Recreational charter fisheries provide important social services and contribute to total species catches. This study compares and validates industry logbook catch and effort data (1,357 trips) against observer data (154 trips) across six ports in a recreational charter fishery in eastern Australia. The mean numbers of clients and fishing effort (hours) per trip varied inconsistently between data sources and among ports. Logbooks did not adequately report released catches, and the mean number of species retained per trip was consistently underestimated in logbooks compared to observer data. For both data sources, catch rates of total individuals and key species displayed similar trends across different units of effort; catch per hour, client, client/hour and trip. The mean catch rates of total individuals and most key species, except those retained for bait, were similar across data sources, as were estimates of total fleet harvests. The length compositions of retained catches of some key species displayed truncation of larger organisms in the observer data whereas other species did not. Despite the shortcomings of the logbook data, future fishery and species monitoring strategies could include industry and observer data sources.     

Efficacy of egg surface disinfectants in captive spawning Atlantic cod Gadus morhua L. and haddock Melanogrammus aeglefinus L.

In an effort to optimize the efficiency of high‐density incubation of Atlantic cod Gadus morhua and haddock Melanogrammus aeglefinus eggs, the per cent hatch of eggs treated with four disinfectants (3% hydrogen peroxide, 1% polyvinylpyrrolidone iodine, 0.1% sodium hypochlorite and a 0.005% antibiotic solution – penicillin/streptomycin) was compared in both species. The per cent hatch of eggs of each species was greatest after a 24 h treatment with the antibiotic solution. The hatching success of eggs treated within the different disinfectant treatments depended upon the embryonic developmental stage in both species. The sodium hypochlorite treatment had the lowest % coverage of colony growth after disinfected haddock eggs were plated onto sterile agar media, highest survival rates to the end of the embryonic period, but the lowest per cent hatch.     

Gear-based management of a tropical artisanal fishery based on species selectivity and capture size

The population density, species composition and lengths of fish landed by artisanal fishermen using six types of gear: large and small traps, gill nets, hand lines, spears and beach seines were studied in the multi‐species fishery of southern Kenya. Selectivity and catch composition among gears were determined by studying the species richness, diversity, size and mean trophic level of the catches for each gear type, to develop gear‐based management recommendations for this artisanal reef lagoon fishery. One hundred and sixty‐three reef and reef‐associated species from 37 families were recorded in the catch. Beach seines and small traps accounted for the highest number of fish landed (34–35 individuals per fisherman per day). These gears also caught smaller fish than big traps, spears and gill nets. Beach seines caught the highest number of species (14 ± 7 species per day) while most other gears caught four to five species per day with no differences between gears. Predatory species with a mean trophic level of 3.6 dominated catches from hand lines, while the mean trophic level of the other gears was low and ranged from 2.6 to 2.9 with no differences between the gears. The high diversity and small size of fish caught in beach seines indicates that its selectivity overlapped most with large traps and gill nets. Spears and small traps also showed high similarity in species selectivity and small traps captured the smaller mean size of fish, indicating that they are likely to pre‐empt the resource of spears. Large traps, hand lines and spears catch the largest individuals and the species composition of the catch differed sufficiently such that their selectivity should overlap the least and may, therefore, be the preferred mix of gears. The elimination or reduction of beach seines and small traps should reduce the catch of small fish and overlap in selectivity among the existing gears.     

Recreational charter fishery attributes and variation in key species catches and discards: Resource management considerations

Strategic long‐term sampling programmes that deliver recreational catch, effort and species demographic data are required for the effective assessment and management of recreational fisheries and harvested organisms. This study used a spatially and temporally stratified observer programme to examine variation in the rates, quantities and lengths of retained and discarded catches of key species in a recreational charter fishery. Geographic region, but not season, significantly influenced catch rates of key demersal species, being driven by temporally persistent latitudinal clines in environmental conditions influencing species distributions. There was considerable trip‐to‐trip variation in catch rates that were attributed to localised differences in fishing operations, locations, environmental conditions and client preferences. Broad trends in retained and discarded catch rates were nevertheless, similar across different fishing effort standardisations (per‐trip, per‐hour, per‐client, per‐client/fished hour), demonstrating that the coarsest unit of effort could be used in fishery assessments. Discard rates of organisms were variable and driven by a combination of mandated legal lengths, individual client and operator preferences for particular species and sizes of organisms, and not due to attainment of catch quotas or high‐grading. This study has identified important fishery attributes that require consideration in assessing charter fisheries and stocks of recreational fish species.     

乳山近海渔业资源种类组成及变化

根据2013—2015年乳山近海拖网渔船的渔捞日志,分析了乳山近海的单位捕捞努力量渔获量、渔获种类组成及生物多样性等特征。结果表明:(1)乳山近海渔获物共有36种,隶属于19目28科33属。其中鱼类有26种,虾蟹类4种,头足类4种,水母类1种,贝类1种。(2)2013—2015年全年优势种差异明显。其中,蓝点马鲛3年均为优势种,鳀鱼是2014年和2015年优势种,网纹狮子鱼为2013年和2015年的优势种。(3)乳山近海渔获物主要集中在休渔期前后的4—5月、9—11月,渔业生产存在明显的春汛和秋汛。2013—2015年乳山近海单位捕捞努力量渔获量逐年增加,但与历史单位捕捞努力量渔获量相比还是存在明显下降;多样性指数和均匀度指数变化趋势一致,多样性指数和丰富度指数较高值出现在秋季;春汛和秋汛期间,渔业资源种属组成及群落结构相似性较高。     

Ichthyophthirius multifiliis: standardization of the infection-response model in Ameca splendens (Miller & Fitzsimons)

Abstract. The goodeid fish Ameca splendens (Miller & Fitzsimons) was exposed to the parasite Ichthyophthirius multifiliis . Exposure levels were 2000,3000,6000 and 12000 theronts per fish. After 3 days, infection levels were determined and the body area of the fish was measured. A rise in the number of trophozoites per fish was observed, up to a level of 6000 theronts per fish. Standardization of infection and response by area, to theronts per square centimetre and trophozoites per square centimetre respectively, produced a significant linear relationship, up to an exposure of 2800 theronts per square centimetre, and also removed the between-tank within-dose variation. The measures of controlling exposure to 1. multifiliis and evaluating response in previous research are reviewed. Adoption of the technique described here will facilitate the collation of research on ichthyophthiriasis by permitting comparisons of different studies utilizing different sizes and species of fish.     

Characteristics and economic contribution of a developing recreational fishery in southern Angola

Abstract  The characteristics and contribution of a developing recreational fishery to the local, regional and national economy of Angola were evaluated in 2006. Annual angling effort was 13 435 h, while the estimated total catch of the three target species [leerfish, Lichia amia (L.), west coast dusky kob, Argyrosomus coronus (Griffiths & Heemstra) and shad, Pomatomus saltatrix (L.)], was 5913 fish with a mass of 27 975 kg. Catch per unit effort (CPUE) for all teleost species combined was 0.44 fish per angler h⁻¹ and 2.08 kg per angler h⁻¹. Total harvest of the three species was 576 fish with a total mass of 2221.6 kg. The total contribution of this recreational fishery (mostly anglers from South Africa) to the local economy was US$ 1007 per harvested fish and US$ 243 per harvested kg. This equated to a contribution to the local, regional and national economies of US$ 151 685, US$ 44 767 and US$ 344 364 respectively. Although the regional contribution was less than half of the national contribution, it was regionally significant when the low population density and the general absence of other formal sector employment opportunities are considered. As a result of the largely undisturbed nature of the southern Angolan coastline, the catch, effort and CPUE information was considered suitable as a baseline for a cost-effective method of future fisheries monitoring in the region.     

Reef fisheries in Porto Seguro, eastern Brazilian coast

Fish landings in Porto Seguro, in the eastern Brazilian coast, were monitored from September 1997 to August 1999 to describe the predominant species caught, the catch per unit effort (CPUE) and patterns of yields according to depth and season. A total of 223.5 t from 352 fishing trips made by a fleet of 53 boats was monitored. The fishery is conducted at depths from 20 to 150 m. The number of commercially valuable species caught was high (n=53). Snappers (Ocyurus chrysurus, Lutjanus analis and L. jocu) made up 38% of total catch. Pelagic species such as Coryphaena hippurus, Seriola dumerili, Thunnus albacares and T. atlanticus accounted for 43% while groupers, mainly Mycteroperca bonaci, represented 10%. Relative abundance of these target species was strongly dependent (P<0.001) upon depth and season. Higher yields of O. chrysurus (>20 kg/fisher per day) were observed between 20 and 40 m, from April to June. During spring–summer, yields of oceanic pelagic species increased rapidly, and catches of C. hippurus (40 kg/fisher per day) rose from November to January.     

黄、东海渔业资源群落结构变化研究

为了解黄海和东海渔业资源群落结构的变化,基于2013年6月(夏季)和9月(秋季)黄、东海渔业资源底拖网调查数据,对渔业资源种类组成、优势种、渔获量空间分布、群落多样性和群落结构进行了研究。结果显示,共鉴定渔业种类185种,其中底层鱼类93种、中上层鱼类31种、甲壳类48种、头足类12种和贝类1种。在鱼类中,鲈形目种类最多,27科47属56种,占鱼类总种类数的45.2%。夏季优势种为鳀(Engraulis japonicus)、脊腹褐虾(Crangon affinis)、带鱼(Trichiurus lepturus)和小黄鱼(Larimichthys polyactis),秋季优势种为三疣梭子蟹(Portunus trituberculatus)、小黄鱼、鳀和带鱼,优势种季节波动不大。秋季平均单位时间渔获量为46.60 kg/h,高于夏季(39.35 kg/h)。秋季航次调查中渔业资源较夏季更为集中,主要分布在长江口和吕泗渔场附近,其他断面渔获量较低。夏季航次群落多样性指数高于秋季航次。CLUSTER聚类分析表明,黄、东海渔业生物群落可分为2组,夏、秋季2组界线变动不大,2组聚类的形成可能受水温和长江径流影响。