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1.
<正> 影响黄渤海对虾增殖的主要问题如下:1 产卵亲虾数量不足产卵亲虾是资源补充量的基础,尤其对一年生的中国对虾来说,补充量的多少是秋汛资源丰歉的决定因素:补充量与产卵亲虾数量呈正相关。产卵亲虾数量之所以不足,不外以下原因:1.1 秋汛对虾捕捞过度根据国家规定,渤海内12000条锚流网船捕捞秋虾,资源利用已饱和化,但由于对虾价格高昂,大量无证渔船违规作业;大量有证渔船在禁渔期内进行偷捕;大量大马力底拖网渔船集中烟威,石 相似文献
2.
渤海对虾亲体与补充量（SRR）动态特性的研究↑（*） 总被引：2，自引：1，他引：2
８０年代以来，渤海对虾的补充量，特别是亲体数量大幅度下降。根据１９８３－１９９４年４月烟威外海对虾亲体资源量指数和渤海秋汛对虾渔获量，按Ｂｅｖｅｒｔｏｎ－Ｈｏｌｔ和Ｒｉｃｋｅｒ模式求得各项参数值，有Ｒ－１ｔ＝３．８６×１０－３＋１．１７×１０－２Ｓ－１ｔＲ２＝０．７４ｐ＜０．００１Ｒｔ＝９０．０５Ｓｔｅ－０．１６２１７ＳｔＲ２＝０．５１ｐ＜０．０１表明：当今渤海对虾亲体对补充量有决定影响，可是８０年代亲体数量的平均值只有６０年代和７０年代的３４．４％和４４．２％；而进入９０年代以来，亲体数量又较８０代下降了２０％。８０年代中期渤海沿岸产卵场的环境条件因对虾养殖业的迅速发展发生了较大变化，养殖面积和单位面积产量大幅度增加。这个新的环境因素对对虾补充量也有一定的影响。渤海对虾亲体数量严重短缺，是恢复和增加对虾补充量的主要限制因素 相似文献
3.
中国对虾是渤海的主要渔业资源。近几年由于捕捞过度等原因,资源处于低谷,更为渔业界有识之士所担忧。亲虾作为对虾资源的补充来源,其资源的丰欠和科学管理将直接影响着秋季补充量的高低。为此,在黄海水产研究所等单位多年调查研究的基础上,1989年由黄海所和黄渤海区渔政局联合对烟威渔场亲虾相对数量进行调查,试图以亲虾相对数量进行秋汛产量预报,并通过亲虾的科学管理,提高对虾资源的补充强度,为对虾渔业振兴提供出路。本文仅对1989年至1994年烟威渔场亲虾相对数量调查进行总 相似文献
4.
渤海湾对虾产卵场调查 总被引：1，自引：0，他引：1
1964—1981年每年5—6月在渤海对虾的主要产卵场渤海湾连续进行了大面积调查。用9XX 周弟网垂直拖取对虾卵子、幼体定量标本,同时观测水温、盐度和饵料生物(微型浮游植物)等,研究对虾卵子、幼体数量分布和变动规律及其与外界环境条件的关系。渤海湾对虾产卵期一般从5月初到6月初持续一个月左右的时间。开始产卵时间的年间变化较大,与对虾性腺发育状况和5月份产卵场水温的高低有关。产卵期的底层水温为13—23℃。对虾产卵场卵子、幼体数量分布的年间变化较大,中心产卵场位于渤海湾水深3—10米,幼体的饵料生物密集在低盐度的海区,适盐范围为23—29‰。卵子、幼体悬浮在整个水体中,定点取样观察表明,卵子、幼体的数量随潮汐的周期性涨落而变动。卵子、幼体数量变动与产卵场产卵亲虾和饵料生物的数量以及平均盐度显著相关。渤海湾对虾世代补充量即幼对虾的相对数量与卵子、幼体数量变动无关。 相似文献
5.
根据1986—2000年对东海和南黄海渔获带鱼的生物学基础调查，利用世代分析方法计算了东海带鱼的资源数量，分析了东海带鱼生殖和补充特征的变动状况，同时研究了环境与带鱼补充量变动的关系。结果表明，随着捕捞压力的增大，东海带鱼的最小成熟体长、产卵亲体的平均体长、平均体重组成进一步缩小，个体繁殖力提高而卵径变小；实行伏季休渔后，东海带鱼的补充群体数量大幅度增加，单位亲体的补充量比伏休前增加45％～60％，证明了伏季休渔的生态效益；带鱼补充群体数量与亲体数量、海中温度、伏休时间成正比。目前东海带鱼的亲体数量仍显不足，应进一步减少对带鱼的捕捞强度。 相似文献
6.
高度不饱和脂肪酸对中国对虾亲虾的产卵和卵质的影响 总被引：18，自引：2，他引：16
用高度不饱和脂肪酸组成和含量不同的四种饲料饲养中国对虾亲虾以研究高度不饱和脂肪酸对中国对韪亲虾产卵及卵质的影响。试验采用脂肪酸组成模式不同的Ｔｉ鱼油,亚麻油,玉米油和猪油为脂肪源配制的饲料对产卵前的亲虾进行６０天的投喂试验,测定了不同脂及到脂肪酸组成的饲料对亲虾产卵量,孵化率和卵脂肪酸组成的影响,并经回归分析结果表明,卵脂肪中的２０：５ω３与产卵量,２２：６ω３与孵化率有相关关系,表明了ＥＰＡ,Ｄ 相似文献
7.
伏季休渔条件下东海带鱼的亲体和补充量关系 总被引：5，自引：0，他引：5
通过对1995-2007年东海带鱼的亲体和补充量资源状况分析,用Ricker繁殖模型和Beverton-Holt繁殖模型分别拟合了带鱼的亲体和补充量关系.结果表明:在现行伏季休渔条件下,东海带鱼的亲体数量和补充量之间存在着相关关系,Ricker繁殖模型的表达形式为R=6.9347P e(-0.033916A),Beverton-Holt繁殖模型的表达形式为P/R=0.10117(9.1645x10(-3)P,二个模型均能拟合东海带鱼的亲体和补充量关系,且拟合结果相近.实施新的伏季休渔政策以来,带鱼的补充量大幅增加.现阶段保护带鱼资源的主要目标是保护亲体和增加产卵群体数量,有效的措施是推迟伏季休渔开捕时间. 相似文献
8.
山东省文登市小观镇育苗厂，利用东方对虾亲体进行夏季人工育苗试验获得成功，1500尾亲虾共育幼苗2000万尾，这一成果填补了东方对虾育苗史上的一项空白，并为对虾人工养殖开辟了新途径。东方对虾育苗一般在冬季进行，夏季人工育苗在育苗领域尚属新课题，夏季育苗亲虾发病率高，并且水温如控制不得当，产卵时间难以达到预定要求。对此，为攻克夏季育苗技术难关，为虾农提供二荐养殖苗源，这个厂与科研部门协作，在二荐育苗上下功夫，早在冬季，他们就备下了1500尾对虾做夏季育苗亲体，将亲虾放人室内暂养池内，严格控制水温，使水温始终保持… 相似文献
9.
辽东湾中国对虾亲体和补充量关系 总被引：1，自引：0，他引：1
渤海中国对虾(包括辽东湾)的亲体与补充量之间的关系已有许多报道,有的报告已在国外发表。由于最近几年渤海中国对虾补充数量继续下降,连续几年处于历史上最低水平以下,引起普遍关注。本文主要用渔业统计 相似文献
10.
三亚产斑节对虾亲虾产卵量的测定 总被引：1，自引：0，他引：1
通过对三亚产斑节对虾亲虾产卵量的测定,结果表明：该市亲虾质量好,个体大。成熟雌性亲虾的体长大多在２１０￣２７０ｍｍ之间,体重在１５０￣２７０ｇ之间,交配率为９０％￣９５％,成熟度高,催熟效果好,重复产卵周期为４￣６天;成熟雌性亲虾的体长大多在１９５￣２３５ｍｍ之间,体重在１１０￣２００ｇ之间;亲虾体长和体重成正比例关系。雌性亲虾的产卵量与个体大小成正比,产卵量多在５０￣８０万粒之间。 相似文献
11.
Explaining recruitment variation in fish is essential for successful fishery management and is consequently under constant review, with an increasing focus on how maternal factors, relative to environmental influences, operate at the level of individual female spawners and extend from the spawning stock through to recruitment. We estimate total egg production (E) in Icelandic summer‐spawning herring (Clupea harengus) from 1963 through 1999 by using sequential population analyses (SPA) and their estimates of stock biomass and recruitment, various size and maturity metrics, and individual fecundity estimates that rely on total length and the condition of the spawners. Generalized linear models indicate that maternal effects are of significance in explaining SPA‐based recruitment‐at‐age‐3 (R). The best model explained 64% of the variation in R and incorporates E constrained to the repeat spawners (40%), the NAO winter index (18%) and ocean temperature (6%). The latter two represent the winter and spring periods subsequent to year‐class formation. Recruit spawner contributions to E were of no significance in explaining variation in R despite the fact that they could contribute as much as 55% of E when their contribution to E was consistently underestimated by a factor of ～ 2, based only on their contribution to spawning stock biomass. We conclude that the spawning potential of the repeat spawners should replace total spawning stock biomass for determining recruitment potential in stock assessment. In addition to the incorporation of oceanographic factors, this would provided a more cautious and risk‐adverse approach. 相似文献
12.
An experiment was conducted to investigate the sperm production of rainbow trout. Eighty-four first-spawners were allocated randomly to three groups to be stripped at weekly, 2-weekly or 4-weekly intervals, respectively. Half of each group were exposed to females. The trial extended over two successive spawning seasons.First-season spawners were modest sperm producers. Depending on the collection frequency they produced mean stripped semen volumes of 1.17 to 1.48 ml containing 7.7 × 109 to 16.8 × 109 sperm. The corresponding means for the second spawning season were 3.54 to 4.59 ml and 22.2 to 35.4 × 109. The spawning season extended from October to April. Production and motility increased from the beginning to mid-season, followed by a gradual decline. The effect of the presence of females was not very evident. With increased frequency of stripping, more sperm/male were obtained. Total semen volume and number of sperm/spawner obtained during the first season with weekly, 2-weekly or 4-weekly collection amounted to 24.6 ml and 160.9 × 109 sperm, 13.4 ml and 135.8 × 109 sperm and 8.9 ml and 101.1 × 109 sperm, respectively. The corresponding values for the second season were 88.9 ml and 546.1 × 109 sperm, 50.3 ml and 377.5 × 109 sperm and 32.1 ml and 247.9 × 109 sperm.From a practical point of view, weekly collection is feasible in second-season spawners, but a maximum of one stripping every 2 weeks appears appropriate for first-season spawners. 相似文献
13.
Febo Lumare 《Journal of the World Aquaculture Society》1981,12(2):335-344
Penaeus japonicus Bate is absent on the Italian coasts, but it is considered a very promising species for national aquaculture. To develop the shrimp-culture on a commercial basis, a convenient method for producing eggs and larvae of Penaeus japonicus was studied. A stock of 156 females, age class 1+ and F3, underwent unilateral eyestalk ablation and they were stocked with males in three plastic tanks (bottom area 14 m2) at a density of 25 individuals/m2 and a sex ratio of 1:1. Conditions of environment and management consisted of: temperature 21±3°C; natural light and photoperiod; total exchange of sea water every day; feeding on mussels. A month after eyestalk ablation the females were inspected every 7–10 days; mature females were transferred to the spawning tanks. Females with well developed gonads averaged 25.0% of the population of females at every inspection; 51.3% of spawners were impregnated with spermatophores; others were inseminated artificially by the method of introducing spermatophores into the thelycum. In six inspections (carried out during a period of 89 days), 3,028,525 eggs were released; a female released 17,500 eggs on the average (maximum was 123,000 eggs, minimum 4,340). The mean rate of fertilized eggs was 52.7%—67.7% from naturally inseminated females and 7.5% from the artificially inseminated ones. The mean hatching rate was 30.9%—40.1% from natural insemination and 3.3% from artificial insemination. Total amount of viable nauplii was 820,550. 相似文献
14.
Brood stock of Atlantic salmon were sampled from 37 rivers or riversystems (strains) for three consecutive years. Each strain was represented by several full- and half-sib families. During the freshwater period each full-sib family was reared separately and each group was given as equal environmental conditions as possible. Fingerlings large enough to become 1-year-old smolt were freeze-branded and smolts from the different strains were sampled and transported to five salmon farms along the Norwegian coast. This paper deals with body weight and length of Atlantic salmon after a growth period of 2 years in the sea.Significant differences between strains were found for all three year classes. The interaction farm × strain was significant but accounted for only a small part of the total variation. It is concluded that genotype × environment interaction can be ignored when planning a selection programme for Altantic salmon for Norwegian farming conditions. A significant interaction sire × dam was found for the 1972 year-class, implying the presence of non-additive genetic variation. The heritabilities for body weight and length estimated from sire components (year-class 1973 and 1974) were quite high: 0.31 and 0.28, respectively. Genetic correlations between body weight and length were close to unity. The heritabilities for condition factor ( were small and none of the sire components were significant. It is concluded that the combination of weight and length used in calculating the K-factor has minor genetic basis.Genetic variation in body weight of Atlantic salmon is high, and about three times as high as for body length. 相似文献
15.
The paper compares two prawn (Penaeus monodon) brood stock systems—land-based tanks and marine offshore pens. Construction costs and annual maintenance and operating costs total US$1,430 and $2,550 for the tank and $1,500 and $3,680, respectively, for the pen. The 12 m3 ferrocement tank requires power for a 24-hour seawater flowthrough and can stock 50 animals/run for a projected yearly production of 8×106 nauplii for 1.2 × 106 juveniles (0.1 to 0.5 g body weight). The 16×16×4 m pen made of bamboo and nylon net materials can accommodate 300 brood stock/run with a projected annual production of 30 × 106 nauplii or 4.5 × 106 juveniles. Discussion includes general requirements, mortality and maturation rates, and criteria for choosing a brood stock system. 相似文献
16.
珠江禁渔对广东鲂资源补充群体的影响分析 总被引：2，自引：0，他引：2
继我国各大水系实施禁渔期制度之后,珠江水系于2011年4月1日至6月1日实现首次禁渔。广东鲂是珠江中下游地区主要的经济鱼类之一,为分析珠江实施禁渔期制度对广东鲂资源补充群体的影响,于珠江实施禁渔制度前(2006—2010年)和禁渔制度后(2011—2012年)在珠江下游肇庆江段设立固定采样点,利用定量弶网对流经该江段的广东鲂鱼苗补充群体进行调查。结果显示,禁渔前,珠江广东鲂鱼苗集中出现在4月中下旬至10月中旬,持续时间为(189±11)d,高峰期为6—8月。禁渔期制度实施之后,全年广东鲂鱼苗出现的起始时间变化不大,但是结束时间提前,持续时间略有缩短,4—5月份广东鲂鱼苗密度明显增大。广东鲂鱼苗总量及其在鱼苗补充群体中的比例均有所提高。根据禁渔前广东鲂鱼苗发生量与径流量之间存在的回归关系:LgY=0.988Lnx-4.932(R2=0.365,P0.01),结合禁渔后实际调查结果,对禁渔的实际作用进行了估算,2011年和2012年由于禁渔分别增加了9.43×108和651.81×108尾广东鲂鱼苗。研究表明,在径流量有保障的前提下,目前的禁渔制度可以有效增加广东鲂鱼苗补充群体资源量。 相似文献
17.
Effects of water temperature and wind on year-class success of Tanner crabs in Bristol Bay, Alaska 总被引：2，自引：0，他引：2
We investigated five a priori hypotheses on factors affecting year-class success of commercially exploited Tanner crabs, Chionoecetes bairdi , in Bristol Bay, Alaska, through correlation analysis and multiple regression modelling. Estimates of recruitment from Zheng et al .' s (1998 ; Can. Spec. Publ. Fish. Aquat. Sci. 125:97–105) length-based analysis of assessment survey and commercial catch data were used to index year-class strength. This work extends results of an earlier study ( Rosenkranz et al ., 1998 ; Alaska Fish. Res. Bull. 5:18–24), which reported positive correlations between Tanner crab year-class size and north-east (NE) winds during the spring larval period, by considering the effects of nondirectional wind speed, bottom and surface water temperature, and abundance of the potential predators sockeye salmon ( Oncorhynchus nerka ) and Pacific cod ( Gadus macrocephalus ). No relationships were found between year-class size and mean wind speed or predator abundance, but positive correlations were found with bottom temperatures during gonadal development and egg incubation. Linear regression models with the independent variables NE wind and bottom temperature accounted for about half the variability in the year-class strength index ( r 2 =0.50 for males, r 2 =0.48 for females). Anomalously cold bottom temperatures may adversely affect the Tanner crab reproductive cycle, and NE winds may promote coastal upwelling while advecting larvae to regions of fine sediments favourable for survival upon settling. The role of Bering Sea oceanography on decadal-scale variability in Tanner crab population dynamics could not be resolved with the relatively short (∼ two decades) time series of stock assessments. 相似文献
18.
Contributions of FOCI research to forecasts of year-class strength of walleye pollock in Shelikof Strait, Alaska 总被引：2，自引：0，他引：2
BERNARD A. MEGREY ANNE B. HOLLOWED STEVEN R. HARE S. ALLEN MACKLIN PHYLLIS J. STABENO 《Fisheries Oceanography》1996,5(S1):189-203
NOAA's Fisheries Oceanography Coordinated Investigations (FOCI) contributes information to help forecast year-class strength of walleye pollock (Theragra chalcogramma ) in the Gulf of Alaska. Quantitative estimates of recruitment are obtained from models of stock assessment and stock projection employing information supplied by FOCI. To generate its information, FOCI convenes specialists in marine biology, physical and fisheries oceanography, meteorology, and statistics to assemble and analyse relevant biological and physical time series with respect to recruitment and processes hypothesized to influence fish survival. Statistical methods encompass linear and nonlinear regression, stochastic simulation modelling, transfer function time series modelling, and tree-modelling regression. The current database consists of 31 years of data, and analyses have identified factors that affect ocean stratification and circulation during spring and summer of the fish's birth year as being important to recruitment. A conceptual model of the recruitment process serves as the framework for a recruitment forecast scheme. A stochastic mathematical simulation model of the conceptual model produces similarities between simulated and observed recruitment time series. FOCI has successfully forecast recruitment observed over the past several years. 相似文献
19.
初始密度对微小亚历山大藻生长及产麻痹性贝类毒素的影响 总被引：1，自引：1，他引：0
为研究微小亚历山大藻生长和产麻痹性贝类毒素(PSP)的规律,采用不同初始密度对微小亚历山大藻进行培养,综合采用显微镜计数、小鼠生物检测(MBA)、高效液相色谱—柱后衍生(HPLC-FLD)等方法分析微小亚历山大藻在不同接种密度条件下的生长和产毒特性.结果表明,随着初始密度增加微小亚历山大藻通过静止期的时间缩短,到达最大生长密度的时间提前,但是生长的最大细胞密度和平均比生长率却呈下降趋势,增值模型反应的情况与观测结果相一致,随着初始密度的增加,依赖于初始种群密度的参数(a)减少,环境容量(K)减少,种群瞬时增殖速度(r)下降.4种不同初始密度(0.05×104、0.10×104、0.15×104、0.30×104cells/mL)条件下,微小亚历山大藻细胞的毒性呈现先增大后减小趋势,在初始密度为0.1×104 cells/mL条件下,同一生长期内细胞毒性比其他3个密度条件下高.HPLC检测微小亚历山大藻含有的毒素为GTX1-4,含量分别为2.14、2.08、4.97、5.04 fmol/cell.综合考虑微小亚历山大藻在生长过程中的细胞最大密度、达到最大密度所用时间以及细胞毒性大小等因数,采用(0.10～0.15)×104 cells/mL接种密度培养微小亚历山大藻,能够达到较好的产毒效果. 相似文献
20.
Weiji Wang Kai Zhang Kun Luo Guangxia Xiao Wenping Song Jie Kong Xianshi Jin 《Fisheries Science》2014,80(4):749-755
We calculated the recapture rates for Chinese shrimp Fenneropenaeus chinensis following hatchery release in Jiaozhou Bay and Bohai Bay in 2012 based on parentage identification using simple sequence repeat (SSR) markers. The results and process were as follows: In total, 3 × 105 postlarval Chinese shrimp (inner marker), comprising six full-sib families, were released into Jiaozhou Bay with a hatchery release of approximately 9 × 107 same-sized stock in the spring. Eight shrimp (inner marker) were identified from 2,507 recapture catches in the autumn, with information about eight SSR loci available by using Cervus 3.0. Similarly, another six full-sib families, comprising 2.04 × 105 postlarvae, were released into Bohai Bay with a hatchery release of approximately 1.6 × 108 same-sized Chinese shrimp of postlarval stock, and four shrimp were identified from 3,232 recapture catches in the autumn. Furthermore, we calculated the number of released stock in the recapture catches, i.e., 2,400 and 3,137 in Jiaozhou Bay and Bohai Bay, respectively. Combined with statistics for Chinese shrimp resources during the autumn fishing season, we calculated that the recapture rates for Jiaozhou Bay and Bohai Bay were 2.70 and 2.59 %, respectively, being slightly lower but more precise compared with results obtained using traditional methods (2.81 and 2.67 %). 相似文献