李湾水库大银鱼移植增殖成效显著

李湾水库位于新密市城西13公里牛店乡李湾村,属淮河流域颖河水系双洎河上游的一座中型水库。流域内为浅山丘陵区,现有水面1200余亩,总库容2500万m~3,具有城市供水、灌溉、防洪、水产养殖等多项功能。水库平均水深14m,最深处约20m,水位稳定,水质清新,无污染,透明度在2.0m以上,水体pH值6.5—7.0,具有丰富的浮游生物、小杂鱼等饵料生物,鱼类区系组成简单,有适宜大银鱼生行的生态灶。水库于1998年初从洛阳陆浑水库移入1000万粒受精卵,当年底形成种群,捕捞大银鱼近1500公斤。     

岱海大银鱼移植增殖技术研究

岱海1987年开始大银鱼移植，1995年产量294t，1996年6－9月试捕均未发现大银鱼。针对大银鱼“失踪”情况，组织专家进行了论证，并对大银鱼进行了重新移植增殖，介绍了重新移植大银鱼技术措施及经验教训。     

云南省银鱼移植增殖的考察报告

云南的太湖新银鱼移植增殖生产始于1979年。当时是由中科院南京地理研究所和云南省水科所分3批次以饮料瓶装运了26万垃太湖新银鱼受精卵，移植到45万亩水面面职的昆明滇池。1981年获得了成功并初步产生了效益。于1983～1986年期间，滇池的银鱼年产量达3500t上下。1984年，云南省科委和省农牧渔业厅联合组织立项推广移植到星云湖等12个湖库。     

大银鱼移植、增殖放流技术的探讨

自１９９５年农业部和水利部发出加速推广银鱼移植、增殖技术的通知以来,我国银鱼移植、增殖技术推广工作取得了显著进展,但也存在不少问题,归纳起来有下列几种情况：其一如河南陆浑水库、山东许家崖水库、内蒙莫力庙水库等水域,是在移植后２～３年,取得了生产性效益...     

银鱼的移植增殖

银鱼原是江苏太湖地区名产,其体色雪白透明,肉嫩味美,营养丰富,已成为淡水渔业中的创汇水产品之一。银鱼移植驯化在我区富川金田、松光脚水库的成功,为我区水库、湖泊等大水面的渔业开发,注入新的内容,增添了新的活力。     

大银鱼亲鱼移植增殖的技术研究

1993年起进行了大银鱼成体移植试验，4座水库均取得了相应的经济效益，最高产值达501万元，移植增倍数平均为18．6倍，水温是亲体移植的关键因子。     

用PAPD方法分析太湖大银鱼、太湖新银鱼和寡齿新银鱼的亲缘关系

１９９６￣１９９７年２年中在太湖６个水域采集到大银鱼（Ｐｒｏｔｏｓａｌａｎｘ ｃｈｉｎｅｎｓｉｓ）、太湖新银鱼（Ｎｅｏｓａｌａｎｘ ｒｅｇａｎｉｕｓ）和寡齿新银鱼（Ｎｅｏｓａｌａｎｘ ｏｌｉｇｏｄｏｎｔｉｓ）并发现其中有２个样品的ＲＡＰＤ图谱与其它样品的图谱有很大差异,进一步ＤＮＡ分析结果表明,这２个样品不属于大银鱼,太湖新银鱼和寡齿新银鱼的其它种银鱼,表明太湖中可能存在５种银鱼。     

银鱼移植及其生物学技术的探讨

银鱼移植是一种投入少、见效快、获益高、方便易行的资源增殖手段,近些年来在我国内陆水域广泛开展。本文介绍了目前我国内陆水域银鱼移植概况,扼要论述了银鱼移植生物学技术,并展望其今后发展前景。     

冯家山水库大银鱼移植增殖工作总结

陕西省拥有各类湖库 1 1 70座 ,2 33万ｈｍ2 ,其中已养水面 1 2万ｈｍ2 ,1 994年平均鱼产量仅 30 0ｋｇ/ｈｍ2 ,水平较低 ,效益甚微 ,一些湖库已面临生存发展的严峻难题。为此 ,从 1 995年起 ,陕西省决定在全省面积在 1 33ｈｍ2 以上的湖库全力开展大银鱼移植增殖工作 ,把它当作救活湖库、脱贫致富的高效捷径来抓。宝鸡市冯家山水库是省里直接抓的重点示范库 ,水面 1 0 0 0ｈｍ2 。该库1 974年竣工 ,库长 1 8 5ｋｍ ,总库容 3 89亿ｍ3 ,平均水深30ｍ。据初步调查 ,水域ｐＨ值 8 1 ,透明度 80～ 1 2 4ｃｍ ,年平均水温 1 1 8℃ ,最…     

黄河口两种鱼类资源密度不同估算方法的比较

以黄河口海域矛尾虾虎鱼(Chaeturichthys stigmatias)和短吻红舌鳎(Cynoglossus joyneri)两种鱼类为例,根据2013、2014年间4个季节月的调查数据,将Δ-分布模型法用于底拖网数据处理,比较基于模型和基于调查设计的两种方法在估算平均资源密度方面的差异,并初步探讨了影响Δ-分布模型法评估效果因素。结果表明,对于8月和10月的矛尾虾虎鱼调查数据,模型法估计的资源密度值小于设计法的估计值,根据其余6组数据计算的资源密度均为模型法更高,数据量和数据分布特征可能是影响Δ-分布模型评估结果的重要因素;8组数据计算所得方差模型法均明显低于设计法;极大值和零值对Δ-分布模型的评估结果有不同的影响。Δ-分布模型是一个稳健的模型,处理数据波动性更小,估计值具有更高的精确度,是一种适于底拖网数据处理和资源评估的模型。     

7处移植公鱼种类的分子鉴定

公鱼属种类曾在中国被广泛移植,但被移植的种类却存在一定的争议,实验利用CO Ⅰ基因序列片段对来自黑龙江、新疆和云南3地7处移植公鱼属种类进行了鉴定,并对它们之间的遗传关系进行了探讨.与GenBank和DNA Barcoding鉴定中心的条形码网站BOLDSystems进行比对,发现3地7处的移植公鱼均与西太公鱼序列相似度达到99％以上;移植公鱼及西太公鱼群体间和群体内的遗传距离均在0.1％～0.3％,与公鱼属其它种类的种间遗传距离则在10％以上;在NJ、Bayesian系统树上,移植公鱼、西太公鱼聚为同一单系,支持率超过98％;以上结果都证明这些移植公鱼均为西太公鱼.研究表明,7处移植公鱼都受到环境的选择压力,但群体间的遗传分化不显著(P=0.066 47＞0.05).在单倍型网络结构图中,它们之间遗传关系和移植路径不明晰,而多次和交叉移植可能是原因之一.     

Lethal limits of high temperature for two crayfishes, the native species Cambaroides japonicus and the alien species Pacifastacus leniusculus in Japan

ABSTRACT: Lethal limits of high temperature were studied to clarify the effects on the survival of the endangered Japanese crayfish species Cambaroides japonicus and the alien species Pacifastacus leniusculus . After the acclimation period for 2 weeks at 16°C, the temperature was raised at a rate of 1°C per week. As a result, the ultimate upper lethal temperatures of C.   japonicus and P.   leniusculus were 27.0 and 31.1°C, respectively, and the lethal temperature for P.   leniusculus was significantly higher than for C.   japonicus . The natural distributions of these two species are discussed in terms of the temperature tolerance.     

Field assessment of two methods for planting the agar-containing seaweed,Gracilaria, in Northern Chile

Two simple methods for mass field cultivation of Gracilaria in Northern Chile were assessed. Thalli fragments were tied either to small rocks or to sand-filled polyethylene tubes to form 120-m² stands, on a shallow (3–5 m depth) sandy marine bottom with an underlying sandstone substratum. Short-term (6 months) thalli growth and resistance to wave action were evaluated on both stands, and the behaviour of these artificial beds was compared with that of a small undisturbed natural Gracilaria bed (ca. 3 ha) near the experimental area. A pilot artificial bed of 2500 m² was also established beside the experimental stands, for long-term assessment of the method using sand-filled tubes.Sand displacement and surfacing of the sandstone substratum due to moderate water turbulence caused a continual decline of the natural bed, but had no apparent effect on the artificial beds. Biomass increment in these plantations was 2600–2800% (fresh weight) in a 6-month period. Intense water turbulence at the end of this period had a significantly less destructive effect on the experimental and pilot beds planted with sand-filled tubes.Three years after the establishment of the pilot bed, natural recolonization had increased its area four-fold, in spite of intense and uncontrolled harvesting during the last year. This behaviour was attributed to the generation of a dense underground thalli system in this bed, due to the strong attachment provided by the sand-filled tubes. At this time (July 1985) underground biomass doubled the standing stock.Under the conditions tested in this study, the sand-filled tube method was the most feasible from a technological point of view.     

A test of two methods for marking larvae and postlarvae of the giant freshwater prawn, Macrobrachium rosenbergii

This paper describes the successful use of two tagging systems, both produced by Northwest Marine Technology Inc., on larval and postlarval giant freshwater prawns, Macrobrachium rosenbergii. Visible implant (VI) elastomer tags (a coloured liquid that solidifies under the epidermis) were used on stage XI larval prawns (mean weight 0.01 g) and postlarval prawns (mean weight 0.07 g). VI alphanumeric tags (small biocompatible plastic labels also inserted under the epidermis) were tested on postlarval prawns (from a weight of 0.5 g). Tags were inserted using clove oil as anaesthetic, and survival, mortality and growth rates of tagged animals were compared with those of controls that were handled but not anaesthetized or marked. Twenty per cent of the larval prawns (the smallest of the group) died just after tagging, but thereafter the remaining prawns survived well, as did all the tagged postlarval prawns. Visibility of the VI elastomer tags in larval prawns deteriorated with time, though 79% of marks were still visible to the naked eye 70 days after tagging. VI elastomer tags in the postlarval group remained clearly visible for up to 100 days. Visibility of the VI alphanumeric tags fell shortly after tagging, but remained adequate thereafter. Moult rates in control and tagged animals were the same in larvae with VI elastomer tags and postlarvae with VI alphanumeric tags, but the moult rate in the postlarval prawns given elastomer tags was slower than in controls. Rates of growth were similar in tagged (elastomer and alphanumeric) and control postlarval prawns, once the size‐dependent mortality of tagged larval prawns was taken into account. We conclude that VI elastomer tags could be used to mark small numbers of individual larval and immediately postlarval prawns for periods of several months, and that VI alphanumeric tags could be used to mark an unlimited number of individuals from a size of approximately 0.5 g.     

Shannon-Wiener多样性指数两种计算方法的比较研究

在应用群落多样性指数评价调查海域群落物种多样性或进行海域生态环境评价时,常用基于样方数据(方法1)或基于区域混合样数据(方法2)2种方法计算Shannon-Wiener多样性指数。为了比较哪种方法所得结果能更好地反映调查海域群落多样性状况,并且分析多样性指数与样本含量的关系,本实验根据2009年胶州湾潮滩湿地大型底栖动物季度调查数据,应用再抽样模拟方法对2种多样性指数计算方法进行了比较研究。结果表明,对于相同样本含量,基于样方数据计算的Shannon-Wiener多样性指数值小于基于区域混合样数据计算的结果。方法1所计算的群落多样性指数与样本含量无关;而方法2计算的多样性指数值随样本含量的增加而增加,并在样本含量为20时接近“真值”并趋于稳定,其相对估计误差(REE)和相对偏差(RB)较小,表明样本含量影响方法2的多样性指数的计算。在评价调查海域群落物种多样性或进行海域生态环境评价时,应该使用基于区域混合样数据的计算方法,并保证足够的样本含量,才能客观地反映海域群落生物多样性现状。     

Comparison of estimates of digestibility of two diets for rainbow trout, Oncorhynchus mykiss (Walbiaum), using two markers and two methods of faeces collection

Estimates of apparent digestibility using an indirect method were made for two rainbow trout, Oncorhynchus mykiss (Walbaum), diets (NF and LT) containing 450 g kg^?1 fish meal. Two inert markers, titanium dioxide and chromic oxide, were used as digestibility markers. Faeces collections were made using two methods: stripping and the Choubert (tank) method. Faecal oil (g kg^?1) and gross energy (GE; MJ kg^?1) were higher for the tank system, but differences were greater for NF (P < 0.001 and P < 0.05 for method X diet interaction, respectively). Faecal titanium and chromium contents were also higher for the tank system, but the differences were greater for LT (P < 0.01 and P < 0.05, respectively). The main method effects were significant for crude protein (CP) and carbohydrate (CHO) content in that values were higher (P < 0.001) for the stripping method. The main diet effects were significant for ash and CHO contents (P < 0.001), with values being highest for LT and NF, respectively. The only significant method X diet interaction for apparent digestibility was with oil (P < 0.01) in that tank values were higher than stripping for NF but not for LT. Marker X method interactions were significant with dry matter (DM), ash, CP, GE, CHO (P < 0.05) and oil (P < 0.01) in that titanium values were lower than chromium values for the tank method. Marker X diet interactions were also significant with DM, ash, CP, GE, CHO (P < 0.05) and oil (P < 0.01) in that titanium values were lower than chromium values for NF. Both methods of faeces collection have inherent weaknesses, but it is suggested that the Choubert method gives more accurate and repeatable estimates of apparent digestibility of diets for fish.     

用于渔业资源调查评估的两种声学手段的比较

采用数字回声探测仪Bio Sonics DT-X(430 KHz)和双频识别声呐DIDSON(低频1.1 MHz、高频1.8MHz)对青草沙水库的渔业资源量、空间分布特征等进行了为期2 d的水声学调查。在调查过程中两种仪器同步工作,并采用放网捕捞的方法对青草沙水库中的鱼类样本进行采集,并测量其体重与体长。利用Echoview软件对两种仪器采集所得的声学数据进行分析处理。DIDSON的调查结果显示:水库鱼类总数约为936万尾,总的资源量约为705万kg,鱼类主要分布于水库的东部、中部地区。Bio Sonics DT-X的调查结果显示:水库鱼类总数约为1 079万尾,总的资源量约为604.24万kg,鱼类主要分布于水库的东北部地区。     

两种罗非鱼生长对照初试

吉富罗非鱼以生长迅速、抢食性强、耐低温、病害少见长,单捷100罗非王具有艳丽的外表、98%以上的雄性率、饵料转化高、生长快等优势,使它们成为罗非鱼养殖的新宠.     

Sound discrimination of two sympatric,threatened fish species allows for their in situ mapping

1. Human impacts on marine ecosystems are increasing and the number of fish species listed in the Red List is constantly growing. In the Mediterranean Sea, seven of the 10 bony fishes defined as Threatened by the IUCN are known to be vocal, including the target species of this study: the shi drum (Umbrina cirrosa Linnaeus, 1758) and the brown meagre (Sciaena umbra Linnaeus, 1758). As a result, non-invasive passive acoustic monitoring (PAM) can be used to pinpoint their distribution at sea. However, for PAM to be effective, reliable acoustic discrimination is required because the sounds they emit during reproduction are remarkably similar (i.e. short broadband pulsed sounds).
2. The shi drum and the brown meagre are closely related, elusive, vocal sciaenids, partially overlapping in their ecological niche. During summer 2019, three PAM surveys were conducted along the tidal inlets of the Venice lagoon (Italy). Here, the calls of both species have been recognized according to their temporal features: shi drum sounds were made up of a lower number of longer pulses with a different envelope, repeated at a lower rate than those of the brown meagre. Further, shi drum and brown meagre sounds of different origins (aquaculture and semi-natural conditions) were analysed and compared with those collected during the survey of the study area in order to validate the field collected data.
3. Call discrimination allowed for a fine-scale species mapping, showing a partially overlapping distribution of the two species along the inlets. This is the first case in which two sciaenids have been documented to share their reproductive habitat in the Mediterranean Sea.
4. This study demonstrates that it is feasible to acoustically monitor the target species even in those parts of the Mediterranean Sea where they co-exist. This, in its turn, could provide managers with the required data for effective conservation measures to be implemented.