光色对豹纹鳃棘鲈幼鱼摄食、生长和存活的影响   总被引：1，自引：0，他引：1  

吴亮  吴洪喜  马建忠  王瑶华  陈婉情  刘志明  关献涛 《海洋科学》2016,40(11):44-51

为探究光色对鱼类摄食、生长和存活的影响,作者在模块化小型循环水养殖系统中,以豹纹鳃棘鲈(Plectropomus leopardus)幼鱼(体长21.2 cm±1.22 cm,体质量112.46 g±2.632 g)为对象,设置5种光色环境(红、黄、绿、白和黑暗),进行了4个月的循环水养殖实验。结果表明:绿光下豹纹鳃棘鲈幼鱼摄食率高、饵料转化率高、饵料系数低,但不同光色下豹纹鳃棘鲈幼鱼的摄食不存在显著性差异(P0.05);幼鱼的体长增长,绿光组和红光组大,且与其余3组间差异显著(P0.05);幼鱼的体质量增长,绿光组最大,红光组和黑暗组次之,白光组和黄光组最小,且三者间差异显著(P0.05);各组幼鱼的肥满度并没有显著性差异(P0.05);除白光组幼鱼存活率(只有50%)最低外,其余各组幼鱼存活率均在80%以上,其中绿光组最高,为88.33%。可见,在循环水养殖生产中,绿光环境有利于豹纹鳃棘鲈幼鱼的摄食、生长和存活。  相似文献   

Diel feeding of the transparent goby Aphia minuta (Pisces,Gobiidae) in the Northwestern Adriatic Sea in spring time          下载免费PDF全文

Valentina Tirelli  Sara Legovini  Diego Borme  Elena Di Poi  Mario La Mesa 《Marine Ecology》2016,37(4):920-926

The present study provides the first estimate of the daily ration for a goby species in the Mediterranean Sea, using a new approach to determine the mass of fish stomach contents through the sum of individual prey dry mass derived indirectly from prey size. Diel feeding activity and daily ration of the pelagic goby Aphia minuta were studied under natural conditions in the coastal waters off Comacchio (Northwestern Adriatic Sea) during the spring season. A total of 318 individuals of A. minuta, collected by 14 trawls carried out on 4 consecutive days, was examined for gut contents. The diel pattern of the vacuity index and the stomach fullness index indicated that A. minuta has nocturnal feeding behaviour. The daily ration, computed over a period of 16 h, was equivalent to 2.23% wet body mass.  相似文献   

Atlantic humpback dolphins Sousa teuszii in the Saloum Delta (Senegal): distribution,relative abundance and photo-identification     

CR Weir 《African Journal of Marine Science》2016,38(3):385-394

During October and November 2015, the first systematic survey of Sousa teuszii was carried out in the Saloum Delta (Senegal, West Africa), comprising 1 617.5 km of boat-based survey coverage. Thirty sightings were recorded in the Saloum and Diomboss rivers, and along the southern coastline. Dolphins were also observed entering the Bandiala and Djinack channels, and travelling across the border into Gambia. The initial sighting locations were 0.043–1.192 km from shore, and tracked dolphins did not move more than 2.082 km from shore. Groups comprised 1–29 animals (mean 9.3 animals), and at least three neonate calves were observed during November. The overall relative abundance was 0.018 sight. km^?1 and 0.175 ind. km^?1. Sightings were concentrated in the Diomboss where relative abundance reached 0.037 sight. km^?1 and 0.331 ind. km^?1. Non-intensive photo-identification produced a minimum population size of 103 animals, the highest recorded for S. teuszii anywhere in its range. Photo-identification also confirmed a movement of individuals between different parts of the Saloum Delta. Combined travel–forage dominated the behaviour. Dolphins were photographed capturing mullet (Mugil sp.) on three occasions. The distribution, population size and movements of S. teuszii are discussed in relation to management.  相似文献   

Ingestion rates and grazing impact of the brackwater mussel Brachidontes virgiliae in Lake St Lucia,iSimangaliso Wetland Park,South Africa     

HA Nel  R Perissinotto  NK Carrasco 《African Journal of Marine Science》2016,38(2):241-248

Bivalves feed on a combination of phytoplankton and zooplankton and have the potential to impact considerably the planktonic biomass, especially when they occur in high densities, such as in oyster and mussel beds. The brackwater mussel Brachidontes virgiliae is numerically dominant during wet phases within Africa’s largest estuarine lake, St Lucia, in the iSimangaliso Wetland Park on the east coast of South Africa. The ingestion rates and potential grazing impact of this small mussel (maximum shell length = 2.5 cm) were estimated for both the wet and dry seasons using an in situ gut fluorescence technique. Ingestion rates were higher during the wet season (5.78 µg pigment ind.^?1 d^?1) than during the dry season (4.44 µg pigment ind.^?1 d^?1). This might be explained by the increased water temperature and food availability during the wet season. Because of the patchy distribution of mussel populations, there could be higher localised grazing impact near mussel aggregations. Results showed a potential grazing impact of up to 20 times the available phytoplankton biomass at specific sites. These high grazing impacts have the potential to deplete phytoplankton stocks in the lake, especially during wet phases in the northern reaches, where mussel densities are highest. This needs to be factored into ecological models of Lake St Lucia, because the system might function differently during increased flood events.  相似文献   

Diel Changes in Vertical Distribution and Feeding Conditions of the Chaetognath Parasagitta elegans (Verill) in the Subarctic Pacific in Summer     

Sohey Matsuda  Akira Taniguchi 《Journal of Oceanography》2001,57(3):353-360

Diel changes in vertical distribution and feeding conditions of the chaetognath Parasagitta elegans (Verill) were observed in three regions of the subarctic North Pacific in the summer of 1997. Samples were collected by repeated vertical hauls with a Vertical Multiple Plankton Sampler (VMPS) for 15–45 hours by demarcating the 0–500 m water column into four sampling layers. Integrated abundance through the entire water column and the proportion of juveniles were higher in the Bering Sea than the western and eastern subarctic Pacific. Juveniles always inhabited the surface layer in the western subarctic Pacific and Bering Sea, but they inhabited the underlying layer in the eastern subarctic Pacific. Stages I–III concentrated into the upper 150 m in the western subarctic Pacific but were distributed widely from 20–300 m in the Bering Sea. Among them, Stages II and III migrated rather synchronously over a wide vertical range in the eastern subarctic Pacific. The feeding rate of P. elegans was calculated to be 0.18 prey/chaetognath/day in the western subarctic Pacific, 0.27 prey/chaetognath/day in the Bering Sea and 0.07 prey/chaetognath/day in the eastern subarctic Pacific.  相似文献   

缢蛏滤除率与颗粒选择性的实验研究   总被引：5，自引：0，他引：5  

范德朋  潘鲁青  马甡  董双林 《海洋科学》2002,26(6):1-4

利用4种不同大小的单细胞藻类作为饵料研究缢蛏（Sinonovacula constricta）的滤除率以及缢蛏对不同大小料颗粒的选择性。实验结果表明：3种规格缢蛏对4种单细胞藻类的滤除率表现出相同的变化规律，即随藻类规格的增大，缢蛏的滤除率亦逐渐变大，并且大规格缢蛏的滤除率变化最显著；在饵料颗粒选择性的实验中，小规格缢蛏对大规格（ESD＝8.83），藻类具有较高的选择性，中规格缢蛏对藻类的选择性不明显，而大规格缢蛏则对小规格（ESD＝4.46）藻类具较高的选择性。  相似文献   

"合信"牌欧鳗配合饲料精养缓长型欧鳗的试验     

吴道爱  俞申启  阮召江  徐顺长 《台湾海峡》2001,20(Z1):119-122

本文报告了"合信"牌欧鳗配合饲料精养缓长型欧鳗的试验.结果表明，试验组的平均饲料效率为48.11％，比对照组提高了10.71％；欧鳗的存活率达99.9％，且有较好的肉质，符合出口烤鳗的要求.  相似文献   

俄罗斯鲟鱼配合饲料主要营养指标的试验   总被引：2，自引：0，他引：2  

林茂苍 《台湾海峡》2001,20(Z1):123-126

用蛋白梯度及脂肪梯度进行工厂化养殖俄罗斯鲟鱼，经过78d养殖试验，认为适宜俄罗斯鲟的蛋白质含量为41％左右，脂肪含量为9％左右.  相似文献   

Trophic Structure and Community Composition of Polychaetes Inhabiting Some Sabellaria alveolata (L.) Reefs Along the Valencia Gulf Coast, Western Mediterranean     

R. Porras    J. V. Bataller    E. Murgui  M. T. Torregrosa 《Marine Ecology》1996,17(4):583-602

  相似文献   

Filter-feeding ascidians (Ciona intestinalis) in a shallow cove: Implications of hydrodynamics for grazing impact     

Hans Ulrik Riisgård  Carsten Jürgensen  Torben Clausen 《Journal of Sea Research》1996,35(4):293-300

The grazing impact by a dense population of filter-feeding ascidians Ciona intestinalis on horizontally flowing water (driven by density circulation) in a shallow cove (Kertinge Nor, Denmark) has been described and quantified by means of a simple one-dimensional numerical model. The agreement between observations and modelled predictions was satisfactory. The applied numerical model has the following analytical solution in the idealized case: Cx = C₀e^−(fx/Y₂), where C_x = algal concentration at a downstream distance x, C₀ = initial concentration, f = F/v_c; F = area specific population filtration rate; v_c = current velocity; Y₂ = depth of mixed layer below halocline. The numerical model quantifies the actual grazing impact while the analytical model illustrates the governing physics in well-known terms. To describe situations with no current (i.e. stagnant water), we performed simulation studies in the laboratory and measured vertical profiles of algal cells over filter-feeding C. intestinalis. The results showed that phytoplankton became reduced in a near-bottom water layer of 20–30 cm thickness. Such water layers may develop in stagnant water (calm days and no advective currents), thus uncoupling the pelagic food and the filter feeders which within a short time will experience extremely meagre food conditions.  相似文献