新疆哈密石城子河流域鱼类群落结构与区系划分

为研究石城子河流域鱼类群落结构特征及区系组成,于2016年5—6月开展了鱼类资源调查。结果显示,石城子河流域有鱼类10种,隶属于2目3科,渔获物优势种为麦穗鱼、鲫鱼以及斯氏高原鳅。鱼类群落结构以杂食性、中下层鱼类为主。斯氏高原鳅、长身高原鳅以及短尾高原鳅为该流域土著鱼类。同历史文献资料相比,鱼类区系已经发生变化。综合分析认为,石城子河流域鱼类区系应划入中亚高山区陇西(山麓)亚区;石城子河流域与河西走廊内陆水系在历史上具有紧密的水力联系;水利工程建设导致的水文条件改变加之人工移植是内陆河流鱼类群落结构及区系组成改变的主要原因。     

两种规格异尾高原鳅幼鱼形态性状对体质量的相关通径分析

正异尾高原鳅(Triplophysa stewartii)隶属鲤形目、鳅科、条鳅亚科、高原鳅属,为小型底栖鱼类,常栖息于河流湖泊浅水处的草丛或砾石之间,主要以剑水蚤、摇蚊幼虫和底栖介形虫为食。高原鳅属分布于海拔5 000米以上的高原,与裂腹鱼共同组成了青藏高原区系鱼的主体,是青藏高原渔业资源的重要组成部分。高原鳅在我国主要分布在青藏高原及邻近区域的河流湖泊中。     

象鼻岭水电站库区江段鱼类资源现状及评价

牛栏江象鼻岭库区江段计有鱼类63种,隶属5目24科(亚科)44属,其中鲤形目有13科(亚科)39属(亚属)50种,鲇形目有4科5属7种,鲈形目有3科3属4种,合鳃目有1科1属1种,鳉形目有1科1属1种。鲤形目和鲇形目为主,占调查河段鱼类种数的90%,数量较多的有裂腹鱼、墨头鱼、盘鮈、圆口铜鱼、长鳍吻鮈、白缘鱼央、叉尾鮠。分析了资源现状,提出了保护和利用措施。     

陕西周至国家级自然保护区鱼类资源初步调查

2016年7月下旬对陕西周至国家级保护区鱼类资源进行调查研究.结果显示:该地区鱼类有1纲(硬骨鱼纲Osteichthyes)2目(鲤形目Cypriniformes、鲑形目Salmoniformes)3科(鲤科Cyprinidae、鳅科Cobitidae、鲑科Salmonidae)5属(鱥属Phoxinus、荷马条鳅属Homatula、高原鳅属Triplophysa、突吻鱼属Varicorhinus、细鳞鲑属Brachymystax)5种,其中优势种为拉氏鱥(Phoxinus lagowskii),中间种和稀有种数量较少.总体而言,陕西周至国家级自然保护区鱼类组成较为简单,群落结构脆弱,丰富性程度不高.     

雅砻江支流安宁河鱼类群落组成及资源现状

为了解安宁河鱼类资源现状,于2013年3月至2014年12月对安宁河及其支流18个采样点进行了5次调查,共计采集鱼类3 113尾,隶属4目、10科、35属、52种,其中长江上游特有鱼类13种;鱼类区系包括中国平原、南方平原、南方山地、中亚山地、北方平原和晚第三纪早期6个区系复合体;其中,中亚山地区系复合体占优(40.4%)。安宁河不同河段Jaccard's相似性指数在0.12~0.47,鱼类群落相似性总体较低。根据IRI(100为优势种)指数计算结果,麦穗鱼(Pseudorasbora parva)、齐口裂腹鱼(Schizothorax prenanti)、红尾副鳅(Paracobitis variegatus)、西昌高原鳅(Triplophysa xichangensis)、斯氏高原鳅(Triplophysa stoliczkae)、东方高原鳅(Triplophysa orientalis)、鲇(Silurus asotus)和白缘鱼央(Liobagrus marginatus)8种鱼类为安宁河优势种。根据个体生物学测量,安宁河主要渔获对象规格较小,齐口裂腹鱼均重285.8 g/尾,红尾副鳅均重7.2 g/尾,鲫(Carassius auratus)均重78.3 g/尾,鲤(Cyprinus carpio)均重361.1 g/尾,鲇均重93.7 g/尾,表明可能存在过度捕捞现象。多样性分析显示,Margalef丰富度指数(R)在1.95~4.47,Shannon-Wiener多样性指数(H)在1.75~2.33,Pielou均匀度指数(E)在0.67~0.73。安宁河鱼类多样性相比同区域其它河流偏低,可能与安宁河鱼类群落受到各种干扰、生境异质性降低、鱼类群落已发生演替有关。对比历史资料,鱼类种类数从82种下降至52种,在不同区域的各分类阶元均有所减少,且有自上而下加重的趋势。水电开发、河道采砂以及资源不合理利用等是影响安宁河鱼类资源的主要因素。基于研究结果,建议尽快加强安宁河鱼类资源保护。     

李仙江鱼类资源的现状与保护对策

2003年5月～2008年4月,对李仙江的鱼类资源进行了调查。共采集鱼类标本7195号。结合历史记录,李仙江共记录鱼类64种(亚种),分属于6目14科43属,其中6种为外来种。李仙江鱼类区系中种类最多的是鲤形目的鲤科,共24属31种;其次为鲤形目爬鳅科和鲇形目鮡科,各为4属7种。近年考察数据显示,李仙江土著鱼类资源呈下降趋势。为保护李仙江土著鱼类资源,应建立鱼类自然保护区和鱼类人工增殖放流站,加强李仙江流域环境保护、生物多样性监测和渔业管理。     

福建松溪鱼类群落的多样性特征

根据2007-2008年松溪8个采样站位鱼类资源的调查资料,分析了松溪鱼类种类组成、优势种、常见种、生态类型以及鱼类多样性等群落结构特点。调查共采集鱼类63种,隶属5目、17科、49属;其中包括外来物种加州鲈（Micropterus salmoides）和罗非鱼（Tilapia sp.）、福建省保护动物鳗尾鱼央（Liobagrus anguillicauda）、福建省特有种纵纹缨口鳅（Crossostoma stigmata）和拟腹吸鳅（Pseudogastromyzon fasciatus）。采用Pin     

李仙江鱼类资源的现状与保护对策

2003年5月～2008年4月,对李仙江的鱼类资源进行了调查.共采集鱼类标本7 195号.结合历史记录,李仙江共记录鱼类64种(亚种),分属于6目14科43属,其中6种为外来种.李仙江鱼类区系中种类最多的是鲤形目的鲤科,共24属31种;其次为鲤形目爬鳅科和鲇形目鮡科,各为4属7种.近年考察数据显示,李仙江土著鱼类资源呈下降趋势.为保护李仙江土著鱼类资源,应建立鱼类自然保护区和鱼类人工增殖放流站,加强李仙江流域环境保护、生物多样性监测和渔业管理.     

塔里木河流域叶尔羌高原鳅大棚养殖技术

叶尔羌高原鳅TriplophysarHedinichthys）yarkandensis（Day）,又名叶尔羌鼓缥鳅、叶尔羌条鳅,地方名狗头鱼。属鲤形目、鳅科、条鳅亚科、高原鳅属、鼓鳔亚属,广泛分布于塔里木河水系,是塔里木河流域中生长较快、个体较大的一种,是生活在塔里木河流域的主要优势土著鱼类之一。叶尔羌高原鳅在鳅科鱼类中属于个体较大的鱼类之一,最大体长可达30．0cm、体重在305g左右。     

沁阳市鱼类资源调查

2016年4月鱼类资源调查队在沁阳市开展鱼类资源调查。根据沁阳市的水系分布特征,共设置18个样点。涵盖沁阳市主要河流,如沁河、潴龙河、蚰蜒河等河流,八一水库等水库。同时前往当地的农贸市场收集鱼类的样本。本次鱼类资源调查共得到鱼类标本30种,隶属于4目9科29属。其中种类最多的是鲤形目,占总数的76.67%;其次是鲈形目,占总数的13.33%;鲇形目有两种,占总数的6.67%;合鳃目一种,占总数的3.33%。根据整理的调查结果表明,沁阳市的鱼类资源丰富,鱼类在食性、生活栖息场所等方面表现出多种多样的特点。根据鱼类区系复合体学说,沁阳市的鱼类资源可以划分为:江河平原区系复合体、北方平原区系复合体、晚第三纪早期区系复合体、北方山地区系复合体、南方平原区系复合体,但江河平原区系复合体存在最多。     

Atlantic Fisheries Technological Conference,Moncton, NB,August 21, 1995

No abstract available for this article.     

Anguilla huangi Teng, Lin, and Tzeng, 2009, is a junior synonym of Anguilla luzonensis Watanabe, Aoyama, and Tsukamoto, 2009

Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.     

Surface disinfection of Pacific threadfin, Polydactylus sexfilis, and amberjack, Seriola rivoliana, eggs

The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L⁻¹ H₂O₂ for 5 min. Exposure to 34 230 mg L⁻¹ H₂O₂ for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L⁻¹ PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>10⁴ cfu egg⁻¹), hydrogen peroxide concentrations of at least 11 340 mg L⁻¹, or PVP‐I concentrations higher than 500 mg L⁻¹ for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L⁻¹) concentrations of H₂O₂ was sufficient to result in high apparent levels of surface sterility (<1 cfu egg⁻¹).     

Marine and coastal protected and conserved areas strategy in Brazil: Context,lessons, challenges,finance, participation,new management models,and first results

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Effects of Mosquitofish,Gambusia affinis,on Channel Catfish,Ictalurus puncatatus,Production Ponds

Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds.     

Age,growth, maturity and the overfishing of the iconic sciaenid,Argyrosomus japonicus,in south-eastern,Australia

Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L₅₀ of 68 cm, whereas males matured at 2–3 years of age with a L₅₀ of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species.     

Reproductive condition of the pearl oyster, Pinctada imbricata, Röding, in Port Stephens, New South Wales, Australia

In an investigation of the potential for pearl production in New South Wales (NSW), Australia, changes in the physical and reproductive condition of the pearl oyster, Pinctada imbricata, were monitored for over 2 years. Using wild oysters gathered from close to the southern extent of the species' range in Port Stephens, NSW, a series of macroscopic and histological observations were made. Reproductive activity in P. imbricata was greatest from late spring to early autumn with oysters in poor reproductive condition during winter. Peaks in reproductive indices occurred in November 1998, March 1999, December 1999 and April 2000. Four indices of physiological condition were used: shell growth, byssal attachment, mantle thickness and mucoprotien layer. With the exception of the thickness and extent of the mucoprotein layer, these indices either showed little variation or the variation that occurred was not related to seasonal or reproductive changes. Changes in the mucoprotein layer were correlated with water temperature and suggest that this layer is metabolized during periods of high demand such as during gonadogenesis. Collectors deployed at two sites in Port Stephens demonstrated that spatfall occurs largely in the months of December and January following the spring and early summer peaks in reproductive activity (November 1998 and December 1999). Spatfall was not observed following the autumnal peaks (March 1999 and April 2000) in reproductive activity. Overall, reproductive patterns in P. imbricata are poorly suited to spat supply in Port Stephens. Farmers require spat in early spring (September) to allow maximum use of the ‘growing’ season (September–May). Reproductively capable oysters are not available from the wild until September and quantity of natural spatfall is too variable and occurs too late in the season (December–January). As a result, oysters are being conditioned in the hatchery in July, spawned in August and spat are supplied to farmers in mid September.     

Brazilian wetlands: their definition,delineation, and classification for research,sustainable management,and protection

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