西北太平洋海域柔鱼产卵场和作业渔场的水温年间比较及其与资源丰度的关系

根据1995-2002年西北太平洋柔鱼的产卵场和索饵场表温及其生产统计数据,对其表温的年间变动及其与资源丰度的关系进行探讨。在20°～30°N、140°～170°E产卵场海域,1995-1997年表温相对较低,而1999年偏高,1998年和2000-2002年则处在中间水平。在39°～45°N、150°E以西索饵场海域,2002年表温处在较低水平,1998-2000年偏高,1995-1997和2001年处在中间水平。在39°～45°N、150°～165°E索饵场海域,1995、1997和2002年表温较低,1998-2000年偏高,1996和2001年处在中间水平。灰色关联表明,产卵场和索饵场的表温及距平均值均对柔鱼资源丰度影响较为显著,其关联度均在0.5以上。资源丰度与距表温平均值的多元线性模型为:在150°E以西海域,CPUE=1.0700+1.6840T1+2.7596T2-2.3177T3;在150°～165°E海域,CPUE=2.5311-1.5226T1+0.1519T2+0.6720T3。     

长江上游白鲟幼鱼形态发育和产卵场的调查研究

１９８９年３月至１９９１年６月对长江重庆江段１９尾白鲟（体长４８０～１１４８ｍｍ）的形态、生长和食性进行了分析及年龄鉴定。结果表明，幼鲟生长较快，身体各部分增长不一致，眼径、吻须增长较慢。其体长（ＢＬ）、体重（Ｗ）的关系式为：Ｗ＝５．２１１９×１０－６ＢＬ２．９２７１。白鲟为肉食性鱼类，体长约６４７ｍｍ的幼鲟主要摄食小型鲤科鱼类。葛洲坝截流后，长江上游白鲟产卵场未变，种群数量有所回升。     

Climate‐induced vulnerability of fisheries in the Coral Triangle: Skipjack Tuna thermal spawning habitats

We investigated projected changes in sea surface temperature (SST) and the associated impacts on spawning habitat for skipjack tuna (Katsuwonus pelamis) in the Coral Triangle region (CT). A multimodel aggregate of SST CMIP5 models for the CT region, based on a comprehensive skill validation assessment, was used to identify the five best performing of 36 models tested for inclusion in a regional multimodel ensemble. Monthly 1° SST multimodel aggregate projections for the CT region under RCP8.5 show that increases in SST, as high as 2.8°C (mean value), will likely occur by the end of this century. Using these estimates of SST change, we applied three parameterizations of skipjack tuna spawning temperatures to assess the potential for change in spawning habitat within the CT region. The three spawning temperature parameterizations were as follows: (a) a square‐wave function derived from catch data with boundaries at 26 and 30°C; (b) a symmetric Gaussian function derived from the SEAPODYM models; and (c) an asymmetric Gaussian function that modifies the SEAPODYM curve in (b) to include the results of relevant physiological experiments. All three parameterizations show similar geographic patterns, with the amount of favourable spawning habitat decreasing throughout the central, equatorial CT region and increasing at higher latitudes. However, the three parameterizations show marked differences in the modelled magnitude of change, with an asymmetric Gaussian function (ASGF) showing a regionwide average of 66.1% decline in favourable spawning habitat between 2015 and 2099. These projected changes in tuna spawning habitats are likely to have important consequences on local and regional fisheries management in the CT region.     

Spatio‐temporal trends of sailfish,Istiophorus platypterus catch rates in relation to spawning ground and environmental factors in the equatorial and southwestern Atlantic Ocean

Spatial and temporal trends of sailfish catch rates in the southwestern and equatorial Atlantic Ocean in relation to environmental variables were investigated using generalized additive models and fishery‐dependent data. Two generalized additive models were fit: (i) ‘spatio‐temporal’, including only latitude, longitude, month, and year; and (ii) ‘oceanographic’, including sea surface temperature (SST), chlorophyll‐a concentration, wind velocity, bottom depth, and depth of mixed layer and year. The spatio‐temporal model explained more (average ~40%) of the variability in catch rates than the oceanographic model (average ~30%). Modeled catch rate predictions showed that sailfish tend to aggregate off the southeast coast of Brazil during the peak of the spawning season (November to February). Sailfish also seem to aggregate for feeding in two different areas, one located in the mid‐west Atlantic to the south of ~15°S and another area off the north coast of Brazil. The oceanographic model revealed that wind velocity and chlorophyll‐a concentration were the most important variables describing catch rate variability. The results presented herein may help to understand sailfish movements in the Atlantic Ocean and the relationship of these movements with environmental effects.     

尖头金线鲃人工繁殖初步研究

用人绒毛膜促性腺激素（HCG）、促黄体素释放激素类似物（LRH—A2）、马来酸地欧酮（DOM）组合对尖头金线鲃（Sinocyclocheilus oxycephalus）催产获得成功,用鲤脑垂体5mg／kg和人绒毛膜促性腺激素1000IU／kg组合催产失败。采取2次注射（第1次注射LRH—A2 2μg／kg,第2次注射LRH—A2 8μg/kg＋DOM3mg／kg＋HCG 1000IU／kg）催产效果明显;采取遮光孵化,孵化率明显提高。     

高活性促性腺激素类似物及其复配制剂在鱼类人工繁殖中的应用

通过催产试验,在高活性促性腺激素类似物相互之间、在类似物与ＨＣＧ之间、在类似物同ＨＣＧ或ＨＷＨＯ复配而成的复配制剂相互之间、在类似物与其复配制剂之间,进行了催产效果的对比。结果表明,各种类似物对不同鱼类的催产效果各不相同;类似物的催产效果明显优于ＨＣＧ;使用类似物复配制剂,其催产效果优于单独使用ＨＣＧ或类似物。     

中国仙女蛤人工育苗试验

2009年在福建平潭进行了2批次中华仙女蛤人工育苗试验。结果表明,亲贝性腺发育成熟程度与催产方法是影响中国仙女蛤亲贝催产成功率和排放率高低的主要因素;在2批亲贝的平均鲜出肉率分别为(31.6±2.0)%和(32.8±2.3)%的前提下,采用阴干、碘钨灯照射提高亲贝体温、流水刺激相结合的物理综合刺激方法可有效地催产中国仙女蛤并培育出健康苗种。但中国仙女蛤亲贝排精产卵的个数比例较小,即亲贝的排放率较低,2批次育苗的排放率分别仅为16.7%和26.7%。2批次共培育出平均壳长为2.87±0.14mm的中国仙女蛤苗种1 331×106cfu。     

Effects of emulsified versus saline administration of GnRHa on induction of ovulation in rainbow trout, Oncorhynchus mykiss

The effects of saline-dissolved or Freund's incomplete adjuvant (FIA)-emulsified GnRHa treatment on the induction of ovulation in rainbow trout, Oncorhynchus mykiss, were examined. The FIA-emulsified GnRHa was first diluted in 0.25 ml physiological saline and then mixed with an equal volume of FIA. Fish were selected in the beginning of the spawning season and were allocated into four groups and were treated intraperitoneally with (a) 0.5 ml of emulsified GnRHa (GnRHa–FIA), (b) 0.5 ml saline-dissolved GnRHa in a single injection (GnRHa-1), (c) 0.5 ml saline-dissolved GnRHa in two injections spaced 1 d apart (GnRHa-2) and (d) 0.5 ml of saline (Control). The GnRHa dose in all hormone treatments was 25 µg kg^− 1. All fish in the FIA–GnRHa and GnRHa-2 groups ovulated within 10 and 11 d after treatment, respectively. In contrast, only 75% in the Control fish and 60% of the fish in the GnRHa-1 group ovulated within 36 d after treatment. None of the treatments caused any pre- or post-spawning mortality in the broodstock. Fertilization, eyeing and hatching percentages of the produced progeny were normal in all the treatment groups and did not differ significantly among them. In conclusion, FIA-emulsified GnRHa can be effective in advancing the onset of and synchronizing the ovulation of rainbow trout within a two-week period, thus shortening the egg collection period, without affecting broodstock survival and egg quality.