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.     

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.     

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.     

Sperm Motilities in Waigieu Seaperch,Psammoperca waigiensis: Effects of Various Dilutions,pH, Temperature,Osmolality, and Cations

The objectives of this study were to evaluate the effects of varying dilutions, pH, temperature, osmolality, and cations on sperm motility parameters in waigieu seaperch, Psammoperca waigiensis. The maximum velocity of average in path (VAP), percentage of motile cells (MOT), and duration of sperm motility (DSM) were observed when semen was diluted in artificial seawater (ASW) at a ratio of 1:100 (144.9 ± 0.6 µm/sec, 95.6 ± 0.4%, and 230.3 ± 2.3 sec, respectively), at 30 C (142.0 ± 0.6 µm/sec, 93.6 ± 0.4%, and 238.3 ± 0.9 sec, respectively), and pH 8 (144.8 ± 0.6 µm/sec, 93.3 ± 0.4%, and 234.0 ± 1.5 sec, respectively). Maximum VAP, MOT, and DSM were obtained in each solution containing 0.6 M NaCl (143.8 ± 1.0 µm/sec, 91.3 ± 2.0%, and 230.6 ± 4.2 sec, respectively), 0.6 M KCl (135.1 ± 3.1 µm/sec, 91.1 ± 3.1%, and 230.3 ± 3.7sec, respectively), 0.2M CaCl₂ (105.3 ± 4.7μm/sec, 47.9 ± 2.7%, and 120.7 ± 1.3 sec, respectively), 0.2 M MgCl₂ (107.3 ± 3.0 m/s, 42.1 ± 3.3%, and 120.3 ± 4.8 sec, respectively), and osmolality of 400 mOsm/kg (145.1 ± 2.5 µm/sec, 93.0 ± 2.1%, and 346.5 ± 4.4s, respectively). We used these mediums as artificial insemination media for fertilizing matured eggs. The results showed that the fertilization and hatching rates in 0.6 M NaCl (75.3 ± 0.6% and 57.0 ± 2.4%, respectively), ASW (70.8 ± 1.2% and 51.2 ± 1.8%, respectively), or 400 mOsm/kg (72.9 ± 1.8% and 55.3 ± 1.6%, respectively) were higher than that in seawater (63.9 ± 1.2% and 39.2 ± 3.9%, respectively). In conclusion, using 0.6 M NaCl, ASW, or 400 mOsm/kg as an artificial insemination medium is effective for fertilizing of waigieu seaperch.     

驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼形态观察

对驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼的形态特征进行了详细的观察与研究,描述了从受精卵到仔、稚、幼鱼各发育期的时间和形态特征变化。结果表明,在水温25-26℃、盐度30的海水中,受精卵历时27 h 25 min完成整个胚胎发育过程,经历从卵裂、囊胚、原肠、神经胚到肌节形成、各器官的逐渐形成、变化、完善等一系列的胚胎发育和变化过程;根据其卵黄囊消长情况、鳞片的覆盖状态、体色发生的不同变化以及第二背鳍和腹鳍的消长,将胚后发育分为仔、稚、幼鱼3个阶段。在水温22-26℃、盐度29-31、DO≥5 mg/L的条件下,2-3 d仔鱼卵黄囊消失,开口摄食;生长发育至31 d,仔鱼已变态进入稚鱼期;培育至57 d,稚鱼完成变态,成为幼鱼。第二背鳍棘和腹鳍棘的生长与收缩等石斑鱼类早期发育的共性生长特征及其体表特性体色变化特征为驼背鲈胚后发育过程中最明显的特征。     

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

1. In the last two decades, Brazil has advanced significantly with the expansion and improvement of its national system of protected areas. Until recently most of the expansion was concentrated in the Amazon region (with useful lessons). It also had an uneven ecological representation of coastal and marine ecosystems, concentrated in coastal waters. Despite significant advances, the levels of funding, staff and stakeholders' engagement remain relatively low for such a vast system.
2. Within the past few years, key elements of a new strategy for protection of coastal and marine areas have started to emerge, combined with some participatory processes and a focus on expansion of the total area protected (from <1.5% protection of the country's marine area). These included: a renewed focus on priority areas for conservation; attention to national and international commitments and targets; clarity about the need for partnerships and funding; better engagement of Brazilian society and stakeholders; new, and more collaborative, models of protected areas management and conservation; and openness in the relationships with wider society.
3. Significant results of this effort have started to appear: new large mosaics of oceanic protected areas were created; Amazon mangroves were recognized by the Ramsar Convention; new mangrove protected areas were created, besides other ones proposed; project proposals are under development with partners for better funding and sharing of responsibility; and there is a better engagement with stakeholders. The building of the Brazilian Blue Initiative is underway.
4. The implementation of the proposed 15‐year marine strategy is at its onset: partnerships need to be strengthened and substantial funding is required. It will only be possible to manage the larger system of protected areas if there are more collaborative and innovative models for protected areas and conservation management. These should include partnerships with civil society, local and traditional communities and the private sector, as well as greater engagement of scientists and research institutions, stronger and more qualified tourism, volunteer work, etc. Further innovative funding mechanisms will also be needed along the way.

     

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).     

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.     

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

No abstract available for this article.     

Factors influencing the abundance of the common bully, Gobiomorphus cotidianus McDowall, in small, North Island, New Zealand, lakes

Adult common bullies, Gobiomorphus cotidianus McDowall, are small (total length =  30–120 mm), benthic fish commonly found in the littoral zones of New Zealand lakes where they are a major prey species for trout and eels. Differences in their relative abundance (CPUE) were determined between 21 shallow North Island lakes. Mean CPUE ranged from 2 to >  1000 fish net^{− 1} night^{− 1} and was inversely related to water transparency. The abundance of bullies was not reduced in lakes containing rainbow trout, Oncorhynchus mykiss (Walbaum), but was reduced in all lakes containing self-recruiting populations of eels, Anguilla spp. Mean densities of planktonic larval bullies in the limnetic zone were also inversely related to water transparency. Since low water transparency is related to increased trophic status for these lakes, the abundance of bullies is likely to be related to lake productivity, rather than turbidity.     

Infection of tilapia, Oreochromis mossambicus (Trewavas), by a marine monogenean, Neobenedenia melleni (MacCallum, 1927) Yamaguti, 1963 in Kaneohe Bay, Hawaii, USA, and its treatment

Abstract A disease of saltwater, cage-cultured tilapia, Oreochromis mossambicus (Trewavas), caused by the marine monogenean, Neobenedenia melleni (MacCallum, 1927) Yamaguti, 1963, is described. Up to 400 parasites were found attached to the body surface of individual fish. Heavily infected fish showed hyperirritability, heavy mucus secretion and discoloration. Pathology was most marked on the eye, with corneal opacity initially, followed by buphthalmos, corneal ulceration and rupture of the eye with subsequent degeneration of internal structure. The infection was successfully treated using 2 min freshwater dips.     

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

相似文献   

Effects of Carbohydrate‐Rich Alternative Feedstuffs on Growth,Survival, Body Composition,Hematology, and Nonspecific Immune Response of Black Pacu,Colossoma macropomum,and Red Pacu,Piaractus brachypomus

To facilitate economical culture of black pacu, Colossoma macropomum, and red pacu, Piaractus brachypomus, in the Amazon region of South America, we assessed locally available alternative energy sources for practical diets. We tested the effects of control diets (containing wheat products) versus diets with different Amazonian feedstuffs (yucca, Manihot sculenta, plantain, Musa paradisiaca, or pijuayo, Bactris gasipaes) on the performance of the pacus in three feeding trials. Black pacu (22.5 ± 0.03 g; Trial 1) or red pacu (2.56 ± 0.01 g; Trial 2) were fed diets containing 30% wheat bran (control) or cooked or uncooked yucca, plantain, or pijuayo for 12 wk. In Trial 3, larger black pacu (86.9 ± 6.4 g) were grown to market size in 24 wk on similar diets. Weight gain, feed conversion, survival, alternative complement activity, and lysozyme were similar among diets. Hepatosomatic index, liver glycogen, and dry matter were affected by diet in Trials 1 and 2, but effects were not consistent among trials. In Trial 3, protein efficiency ratio was lower in fish fed the diet containing wheat middlings. However, relative to wheat bran or wheat middlings, all feedstuffs tested were effective energy sources for juvenile black pacu and red pacu.     

Effects of Dietary Savory and Myrtle Essential Oils on Growth,Survival, Nutritional Indices,Serum Biochemistry,and Hematology of Farmed Rainbow Trout,Oncorhynchus mykiss,Fry

The effects of diets containing different levels of essential oils from savory Satureja khuzestanica Jamzad and myrtle Myrtus communis L and an immunity complement were investigated on growth, survival, nutritional indices, serum biochemistry, and hematology of farmed rainbow trout, Oncorhynchus mykiss, fry (n = 4500; 5 ± 2 g). The essential oils were dosed as 300 and 500 mg/kg diet. After 60 d, the fish fed 300 mg/kg of the essential oils showed the highest counts of white blood cells (P < 0.05). The same treatment revealed the greatest levels of hematocrit, total protein, and albumin, but glucose and cholesterol values significantly decreased compared with the control (P < 0.05). Feeding fish with 300 mg/kg of the essential oils led to highest records of specific growth rate and survival rate but the lowest feed conversion ratio (FCR), and those fed with immunity complement attained the lowest values of growth parameters. The fry fed with immunity complement and 300 mg/kg of myrtle essential oil achieved the highest and lowest FCR values, respectively. The results indicate that dietary supplementation of 300 mg/kg of the above essential oils exert positive impacts on the growth performance, feeding efficiency, and hematological factors in O. mykiss.     

Pigmentation and growth performance in the blue gourami,Trichogaster trichopterus,fed marigold,Calendula officinalis,powder, a natural carotenoid source

The present study aimed to determine the effects of different levels of marigold, Calendula officinalis, powder, 0 (control), 0.5% (M0.5), 1.5% (M1.5), and 2.5% (M2.5), on pigmentation and growth performance of the blue gourami after a 70‐day trial. At the end of the experiment, no significant differences (p > 0.05) were found in fish growth performance and body compositions. Color parameters (L*, a*, and b*) were weekly evaluated by examining a point posterior to the fish operculum. The marigold‐fed fish were darker than the control fish at Weeks 9 and 10. Yellowness intensity of the M2.5 was significantly higher than the other treatments at Week 9. Skin and caudal fin total carotenoids, astaxanthin, canthaxanthin, and β‐carotene contents of the treatment M2.5 were significantly different (p < 0.05) compared to the other treatments. Muscle total carotenoids, astaxanthin, and canthaxanthin contents of the marigold‐treated fish were significantly (p < 0.05) higher than the control group. Muscle β‐carotene contents of the treatments M1.5 and M2.5 were significantly (p < 0.05) higher than the control group. This study shows that marigold powder may be considered an efficient natural carotenoid source for pigmentation in blue gourami.     

Growth,Survivorship, Air‐bubble Disease,and Attachment of Feeble Juvenile Seahorses,Hippocampus kuda (Bleeker, 1852)

Seahorse aquaculture has been a focus for meeting the demand of traditional medicine and aquarium. Feeble (poor quality) juveniles are commonly found in the commercial seahorse culture. In this study, we compared the growth and survival performances of the feeble and healthy common seahorses Hippocampus kuda. The results show that the feeble juveniles had high growth and survival at the temperature of 27–29 C and salinity of 26–28‰ with frequent feeding (≥three times a day) during first 5 wk. Through a 12‐wk investigation, we found that the air‐bubble disease could significantly affect the specific growth rate and survival of the feeble juveniles. There was a positive and significant correlation between the substrate‐attachment rate and survival rate in the feeble juveniles, and substrate‐attachment rate may be used to assess the quality of the feeble populations in the seahorse H. kuda.     

Low allozyme variation in snapper, Pagrus auratus, in Victoria, Australia

The population genetic structure of snapper, Pagrus auratus (Bloch and Schneider), in Victoria was investigated using six polymorphic allozyme loci. Fish were sampled from four sites in Victoria and single locations in South Australia, Western Australia and New Zealand. Although there were distinct genetic differences between the snapper populations from each of the Australian states and New Zealand, only minor and largely insignificant differences were detected among Victorian populations. The results are consistent with previous genetic and tagging studies that indicate no mixing between snapper stocks in Victoria and Spencer Gulf in South Australia. This justifies separate management of the snapper fisheries in these regions. The low levels of polymorphism and heterozygosity in Victorian snapper suggest an isolation by distance model of population structure rather than one of discrete subpopulations.     

Effect of Lead on Survival,Osmoregulation, and Histological Changes of the Gills of the White Shrimp,Litopenaeus vannamei,Boone, 1931

The purpose of this study was to evaluate the acute toxicity of lead for different life stages of shrimp, Litopenaeus vannamei, and to determine the effect of its sublethal concentrations on osmoregulatory capacity (OC) as well as the possible histological alteration in the gills of juvenile shrimp. The 24‐, 48‐, and 96‐h LC₅₀ values for lead to L. vannamei increased progressively with increasing life stage, from nauplii < zoeae < mysis < postlarvae < juvenile. After 15‐d exposure to 3.25, 6.50, and 9.75 mg Pb/L, the OC values of exposed shrimp were reduced by 39, 73, and 157%, respectively compared to control animals. Compared to controls, the lead concentrations in gill tissues increased significantly by 127,500, 137,500, and 141,000% in shrimps exposed to 3.25, 6.50, and 9.75 mg Pb/L, respectively. After lead exposure, hemocytic congestion in efferent vessels and multiple hyperplasia were observed in gill filaments, resulting in narrowed hemolymphatic lacuna. The histopathological effects increased with increasing Pb concentration.     

Recruitment strategy of swimming crab, Portunus trituberculatus, in Hiuchi-Nada, Japan

The recruitment strategy of swimming crabs, Portunus trituberculatus, was investigated by field observations and numerical experiments in Hiuchi-Nada, Japan. Calculated dispersal patterns of zoeal and megalopal stages in a three-dimensional numerical model reproduce observed patterns accurately. The temporal change of vertical migration patterns between the 1st and 2nd zoeas and the 3rd and 4th zoeas plays an important role in the process of recruitment of P. trituberculatus from spawning ground to nursery ground.     

Effects of levamisole,echinacea, and thyme oral administration on growth factors,blood parameters,and immunity in beluga,Huso huso

A total of 180 fish (95.50 g) were fed with 0.1% levamisole, 0.5% thyme, and 0.5% echinacea crude extract for 60 days. The control group received no stimulant. The results of growth parameters indicated a significant positive effect of levamisole in comparison with the control group, though it was not significantly different from echinacea and thyme treatments (P > 0.05). No mortalities were observed in the treatments. Feed conversion ratio and protein efficiency ratio did not differ significantly between the treatments. The highest numbers of white and red blood cells and the greatest amounts of hemoglobin and hematocrit were detected in the levamisole treatment, showing significant differences with the other groups in the percentage of hemoglobin only (P < 0.05). The highest levels of MCH and MCHC were also measured in the levamisole treatment. Differential count of white blood cells revealed no significant differences in neutrophil and lymphocyte levels with the control. There was a significant increase in the percentage of eosinophil in the levamisole treatment alone. No significant differences were recorded in total protein, albumin, and aspartate aminotransferase and alanine aminotransferase enzymes. Levamisole treatment displayed the highest activities of glutathione peroxidase and lysozyme as well as the greatest amount of immunoglobulin. So 0.1 levamisole yielded better results in the growth, blood, and immunity parameters and can be used as a stimulant without injuring body organs.