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1.
The spawning habitat of Emmelichthys nitidus (Emmelichthyidae) in south-eastern Australia is described from vertical ichthyoplankton samples collected along the shelf region off eastern through to south-western Tasmania during peak spawning in October 2005–06. Surveys covered eastern waters in 2005 (38.8–43.5°S), and both eastern and southern waters in 2006 (40.5°S around to 43.5°S off the south-west). Eggs (n = 10,393) and larvae (n = 378) occurred along eastern Tasmania in both years but were rare along southern waters south and westwards of 43.5°S in 2006. Peak egg abundances (1950–2640 per m−2) were obtained off north-eastern Tasmania (40.5–41.5°S) between the shelf break and 2.5 nm inshore from the break. Eggs were up to 5-days old, while nearly 95% of larvae were at the early preflexion stage, i.e. close to newly emerged. Average abundances of aged eggs pooled across each survey declined steadily from day-1 to day-5 eggs both in 2005 (97-18) and 2006 (175-34). Moreover, day-1 egg abundances were significantly greater 2.5 nm at either side of the break, including at the break, than in waters ≥5 nm both inshore and offshore from the break. These results, complemented with egg and larval data obtained in shelf waters off New South Wales (NSW; 35.0–37.7°S) in October 2002–03, indicate that the main spawning area of E. nitidus in south-eastern Australia lies between 35.5°S off southern NSW and 43.5°S off south-eastern Tasmania, and that spawning activity declines abruptly south and westwards of 43.5°S around to the south-west coast. In addition, quotient analyses of day-1 egg abundances point to a preferred spawning habitat contained predominantly within a 5 nm corridor along the shelf break, where waters are 125–325 m deep and median temperatures 13.5–14.0 °C. Spawning off eastern Tasmania is timed with the productivity outburst typical of the region during the austral spring, and the temperature increase from the mixing between the southwards advancing, warm East Australian Current and cooler subantarctic water over the shelf. Overall, ichthyoplankton data, coupled with reproductive information from adults trawled off Tasmania, indicate that E. nitidus constitutes a suitable species for the application of the daily egg production method (DEPM) to estimate spawning biomass. This finding, together with evidence in support of a discrete eastern spawning stock extending from southern NSW to southern Tasmania, strengthens the need for DEPM-based biomass estimates of E. nitidus prior to further fishery expansion.  相似文献   

2.
Despite much public awareness surrounding the annual migration of sardine Sardinops sagax northward along the east coast of South Africa in winter each year, relatively little research effort has been expended to improve understanding of the ‘sardine run’. For this reason, a dedicated multidisciplinary survey, timed to coincide with the annual sardine run, was conducted off the East Coast in June and July of 2005. The major objective of the survey was to estimate the biomass of sardine off the East Coast during the run, and to compare this with biomass estimates collected during previous surveys conducted in this area during the late 1980s when the South African sardine population was at a considerably smaller size. We also collected data on the distribution of sardine and other small pelagic fish species and their eggs, the biological characteristics of sardine during the run, and data on the hydrography (temperature and currents) and lower trophic levels (phytoplankton and zooplankton) of the region. Results suggest that the biomass of sardine off the East Coast in winter remains relatively small and consistent, regardless of overall sardine population size. The narrow continental shelf to the east of Port Alfred, which is dominated offshore by the fast-flowing warm Agulhas Current, constrains the amount of suitable habitat for sardine and other clupeoids such as anchovy Engraulis encrasicolus, West Coast round herring Etrumeus whiteheadi and East Coast round herring Etrumeus teres, and hence precludes these species from attaining a high biomass in this region. Additionally, primary and secondary productivity levels are much lower than elsewhere on the western and eastern Agulhas Bank off the south coast of South Africa, suggesting that the sardine run is not a feeding migration. A previous hypothesis that the run is mainly a result of an expansion of the distributional range of these fish as conditions become favourable in winter due to sporadic cooling off the East Coast is also not entirely supported by results from the survey. It is suggested that a migration for the purposes of spawning off this coast when conditions become favourable is a more likely incentive for sardine to undertake this arduous journey, despite increased predation and poor feeding conditions.  相似文献   

3.
One of the present concerns of fish biologists involves defining and identifying nursery habitats in the context of conservation and resource management strategies. Fish nursery studies usually report upon nursery occupation during the latter juvenile stages, despite the fact that recruitment to nurseries can start early in life, during the larval phase. Here we investigated the use of a temperate estuarine nursery area, the Lima estuary (NW Portugal), by initial development stages of flatfish species before and after metamorphosis, integrating the larval and juvenile phases. The Lima estuarine flatfish community comprised twelve taxa, seven of which were present as pelagic larvae, six as juveniles and three as adults. There was a general trend of increasing spring–summer abundance of both larvae and juveniles, followed by a sharp winter decrease, mainly of larval flatfishes. The Lima estuary was used by Solea senegalensis, Platichthys flesus and Solea solea as a nursery area, with direct settlement for the two first species. In contrast, indirect settlement was suggested for S. solea, with metamorphosis occurring outside the estuarine area. Estuarine recruitment of S. senegalensis varied between years, with young larvae occurring in the estuary throughout a prolonged period that lasted 6–9 months, corroborating the protracted spawning season. P. flesus, the second most abundant species, exhibited a typical spring estuarine recruitment, without inter-annual variations. Developed larvae arrived in the estuary during spring, whereas the 0-group juveniles emerged in the following summer period. The present study contributes new insight to our understanding of the economically important S. senegalensis, and highlights the importance of integrating the planktonic larval phase into traditional flatfish nursery studies.  相似文献   

4.
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5.
Twice monthly sampling over two 16 month periods at a shallow site on Newfoundland's east coast showed the fish assemblage to be dominated by four taxa (Gasterosteus aculeatus, G. wheatlandi, Osmerus mordax, Gadus spp.) that accounted for 96% of the individuals collected. Of the 16 479 fish measured, 65% were adults based on the estimated size of first spawning. The fish assemblage was dominated (86%) by species with demersal eggs, several of which spawn at the same shallow sites used by juveniles as nursery sites. Coastal spawning and demersal eggs maintain offspring in coastal nursery areas where survival is thought to be increased. Number of species and number of fish were both correlated with water temperature being highest from mid-summer to early autumn and lowest in winter. Temperature, time of spawning, and movements of juveniles and adults facilitated grouping species into five assemblages based on seasonal abundance: seasonal periodic species (summer and winter), regular species, regular species collected in all seasons except winter, and occasional (rare) species. At the diel scale, two consistent species groupings were observed: species that showed no significant difference between day and night and species caught primarily at night. Number of night species exceeded day species by a factor of two. No seine-caught species in shallow water exhibited significantly higher catches during the day. Observations by SCUBA divers indicated some species were more abundant during day time at slightly deeper depths. This observation in conjunction with day and night seining in shallower water, suggests these species aggregate in deeper water during day and move to shallow waters at night.  相似文献   

6.
根据2011年及2013?2018年春、秋两季在海州湾及其邻近海域进行的底拖网调查数据，研究该海域短吻红舌鳎(Cynoglossus joyneri)的资源分布特征及其受环境因子和饵料生物的影响，并比较了两种模型(普通GAM模型和PCA-GAM模型)对其资源分布的预测效果，采用交叉验证的方法对模型的预测能力及拟合效果进行评价。结果显示:PCA-GAM模型的拟合度及预测效果均优于普通GAM模型。春、秋两季海州湾短吻红舌鳎资源丰度均呈现南高北低、近岸浅水区大于深水区的分布特征，因为海州湾南部近岸海域较高的水温利于春、秋季短吻红舌鳎产卵群体性腺发育，较低的盐度利于其鱼卵及仔鱼的生长发育，同时，近岸海域丰富的饵料资源为产卵后的亲体提供大量食物供给。分别应用两种模型预测了2018年春季和秋季短吻红舌鳎在海州湾的资源分布，结果显示，PCA-GAM模型的预测值与实际调查的结果更为吻合，预测效果要优于普通GAM模型。本研究为今后开展渔业生物空间分布的研究提供了一种新的方法。  相似文献   

7.
Transport between shelf and offshore environments supports a significant proportion of ocean primary productivity and is critical to the life cycle of many marine species. While fundamental differences in the underlying dynamics of eastern and western boundary currents have been recognized and studied for more than half a century, the implications for physical dispersal rates have received much less attention. In this study we explore how Australia’s two major boundary current systems, the East Australian Current and the Leeuwin Current, differ in their local retention and cross-shore transports in the upper water column and how these differences favor contrasting life histories of small pelagic fishes. The results suggest that the East Australian Current forms a partial barrier to onshore transport, but is effective in entraining shelf waters and transporting them offshore, particularly in the region where the current separates from the coast. Blue mackerel (Scomber australasicus) spawn on the outer-shelf in this separation region and may thereby maximize the dispersion of eggs and larvae in the mainly oligotrophic waters of the southern Coral Sea. In contrast, the Leeuwin Current system promotes onshore transport through the combined effects of mean onshore flow and eddy-induced mixing. In the Great Australian Bight, sardine (Sardinops sagax) and anchovy (Engraulis australis) may exploit the high coastal retention of the Leeuwin Current system by spawning on the inner-shelf during summer when the current is weakest and winds assist retention and enhance production through local upwelling.  相似文献   

8.
Seasonal and short-term variability of environmental parameters influence the spawning strategies of fish species. In this study, the spawning strategies and the transport of early stages of the two Cape hake species off South Africa were investigated. Distribution of eggs and larvae of Merluccius paradoxus and M. capensis was analysed in order to derive more detailed and species-specific information on spawning season, spawning location, and transport of early stages. Samples were collected during three pilot surveys between January and October 2007 and during an extensive survey in September/October 2008 in the southern Benguela upwelling system off South Africa. Eggs and larvae of M. paradoxus were found in greater numbers than those of M. capensis during all surveys. Highest abundances were found from September to October, indicating one spawning peak for M. paradoxus during late austral winter to spring. The western Agulhas Bank was identified as the primary spawning ground, and smaller spawning events occurred on the West Coast. Larvae of both species were mainly distributed in subsurface waters between 25 and 100 m. More than 50% of all larvae caught had a total length between 3 and 4 mm and size increased significantly with decreasing latitude. Merluccius capensis were found closer inshore than M. paradoxus, indicating that early stages of the two species followed separate drift routes. We assume that this distribution pattern most likely evolved from differences in spawning location and phenology. The spawning strategies of M. paradoxus and M. capensis are well adapted to a time-frame of optimal transport conditions favourable for larval survival in the highly variable environment of the southern Benguela upwelling system, but the peak spawning of the two species is separated in time and space.  相似文献   

9.
2013年4月，2014年5月，2012年6月和2015年10月在印度尼西亚北部苏拉维斯蓝碧海峡（Lembeh Strait）进行了4个航次的海洋生态调查，研究了蓝碧海峡的浮游植物种类组成，以及浮游植物群落结构的季节变化及其驱动因子。四个航次的调查中记录了5类浮游植物和416个种（类）。调查区浮游植物密度平均为2348cells/L，硅藻和甲藻种类最多。蓝藻种类最少，但丰度很高。季风转换期的4月份和10月份浮游植物丰度总量较低，东南季风期间5月份和6月份的浮游植物丰度较高。除了束毛藻（Trichodesmium）之外，常见种是浮游硅藻。浮游植物的丰度和多样性的季节性变化明显。海链藻（Thalassionema）、拟菱形藻（Pseudo-nitzschia）和蓝藻类的束毛藻对群落的不相似性贡献最大。由于蓝碧海峡南部营养盐浓度较高，南部水域的硅藻和甲藻密度稍高于海峡北部。虽然，南北两个水体中蓝藻的分布趋于均匀，但蓝碧海峡南部也有较高密度。与雅加达湾以及中国的一些海湾相比，蓝碧海峡的浮游植物丰度相当低。分析表明，SE季风期间上升流营养盐是左右浮游植物丰度月变化的重要因素。蓝碧海峡浮游生态系原始，且接近天然本底，人类活动背景噪声低，能够清晰地响应大环境的变化，是研究浮游生态系统的理想区域。  相似文献   

10.
A relationship between body size and time of spawning has often been described for both pelagic and non-pelagic fish species that migrate for the purpose of spawning. The present study investigates this relationship for capelin (Mallotus villosus), a pelagic smelt-like species that spawns on the beaches of Newfoundland. Simple linear regressions were carried out separately for three groups of capelin: ovid females, spent females and males in three successive years (1982–1984). Bigger fish arrived near the spawning grounds first, for all three groups in all three years and was most obvious for female capelin. Analyses of stomach contents of Atlantic cod (Gadus morhua), an important predator of capelin in the Newfoundland area, showed a similar decrease in mean size of capelin throughout the capelin spawning season in June, July and August. Furthermore, analyses strongly suggest that early in the spawning seasons, when capelin abundance was high, cod selected for bigger capelin, whereas towards the end of the spawning seasons, when capelin abundance was low, cod did not show any size preference.  相似文献   

11.
褐毛鲿全人工繁殖技术研究   总被引：1，自引：0，他引：1  
为了掌握褐毛鲿(Megalonibea fusca)繁殖生物学特性并突破全人工繁殖技术,作者介绍了1998～2002年项目实施期间,对褐毛鲿的性成熟年龄、生殖季节、产卵水温、性腺发育与性周期、产卵类型与产卵量、室内产卵池催产、海上网箱催产、亲鱼产卵率、受精率、催产激素与剂量、全人工繁殖技术等所做的研究,讨论和总结了褐毛鲿亲鱼的强化培育,人工催产的方法与措施。  相似文献   

12.
Since the late 1980s, the small-sized non-commercial flatfish species solenette (Buglossidium luteum) and scaldfish (Arnoglossus laterna) have increased in abundance in the southern North Sea. Because these species are considered as possible competitors for prey of commercial flatfish, this study aimed at advancing knowledge of their feeding ecology.Between January 2009 and January 2010 stomach contents of solenette and scaldfish and benthic infauna were sampled seasonally in a study area in the German Bight. The objectives were to investigate the seasonal variability of feeding activity and diet composition of both flatfish species related to benthic prey availability.For both flatfish, the highest feeding activity was found in summer, at the same time that the highest prey densities occurred in the study area. A reduced feeding activity was observed during the winter of 2010, but not in the winter of 2009, probably related to higher 2009 water temperatures.In all seasons, diet composition of solenette was dominated by meiofauna, mainly harpacticoid copepods. Macrofauna prey species, namely juveniles of bivalves and echinoderms became important in spring. An increase in amphipods and cumaceans was found in the stomach contents during summer and autumn, simultaneously with their increased abundance in the benthic infauna. In contrast, polychaetes were rarely found in the diet, but dominated the infauna during all seasons.Diet composition of scaldfish was dominated by larger and mobile prey, and, during all seasons, was mainly comprised of crustaceans. Amphipods characterised the diet in both winters, while decapods such as Crangon spp. and Liocarcinus spp. were the dominant prey from spring to autumn. Additionally, juveniles of flatfish (Pleuronectids) and bivalves were found in the scaldfish diet in spring, replaced by cumaceans in summer. No dietary overlap between both flatfish species was found across seasons, indicating partitioning of prey resources between solenette and scaldfish. Their different feeding strategies and prey preferences, in turn were influenced by the seasonal variability of available prey.  相似文献   

13.
Abundance, population structure and production of the macro-invertebrates belonging to the functional feeding group of the shredders were studied in the Ichkeul wetland, northern Tunisia, from July 1993 to April 1994. Mean above-ground macrophyte biomass was at a maximum in September followed by a complete breakdown of the Potamogeton pectinatus L. meadow from October onward due to high salinity following an exceptionally dry winter. Only the meadow of Ruppia cirrhosa (Petagna) Grande at Tinja remained in place. Abundance of Gammarus aequicauda (Martynov 1931), Idotea chelipes (Pallas 1766) and Sphaeroma hookeri Leach 1814 was significantly related to the R. cirrhosa biomass. Gammarus aequicauda presented two recruitment periods in spring and autumn, and S. hookeri a third one in winter. The population of I. chelipes was renewed during winter by continued reproduction without any spring generation. Recruitment of all three species was not very successful during the study period. Life span of all three species was between 12 and 15 months. Despite their relatively low biomass and production rate, the shredders have a key function in processing macrophyte matter to different trophic levels through fragmentation and accelerating the decomposition of macrophyte biomass accumulated at the end of the growth season in the Ichkeul lagoon.  相似文献   

14.
There is a growing need to incorporate biotic interactions, particularly those between predators and their prey, when predicting climate-driven shifts in marine fishes. Predators dependent on a narrow range of prey species should respond rapidly to shifts in the distribution of their prey, whereas those with broad trophic adaptability may respond to shifts in their prey by altering their diet. Small pelagic fishes are an extremely important component of the diet of many marine predators. However, their populations are expected to shift in distribution and fluctuate in abundance as the climate changes. We conducted a comparative study of the seasonal diet of adult Pomatomus saltatrix over two periods (June–December 2006 and 2012) and examined the available data on small pelagic fishes biomass in a global hotspot (the coastal region of southern Angola, southern Africa) to gain an understanding of the tropic adaptability of the species. Despite a drop (630 000 t to 353 000 t) in the abundance of their dominant prey (Sardinella aurita) in the region, it remained the most important prey item during both study periods (Period 1 = 99.3% RI, Period 2 = 85.3% RI, where %RI is a ranking index of relative importance). However, the diet during Period 2 was supplemented with prey typically associated with the nearshore zone. The seasonal data showed that P. saltatrix were capable not only of switching their diet from S. aurita to other prey items, but also of switching their trophic habitat from the pelagic to the nearshore zone. These findings suggest that P. saltatrix will not necessarily co-migrate if there is a climate-driven shift in the distribution of small pelagic fishes (their dominant prey). Accordingly, understanding the trophic adaptability of predators is critical for understanding their response to the impacts of climate change.  相似文献   

15.
Environmental variables have been measured and sampling for ichthyoplankton has been conducted monthly, since April 2001, at three stations, located at the inner (1), middle (2) and outer (3) shelf of the central Cantabrian Sea. This paper presents the results of the study of the ichthyoplankton collected from July 2001 to June 2004. Fish larvae from 99 species, belonging to 37 families, were identified. Families with higher number of species were Gadidae, Sparidae and Labridae. The larval fish assemblage was dominated by pelagic fish species, with Sardina pilchardus, as the most abundant. There was a pronounced spring peak in larval abundance, dominated by S. pilchardus. A smaller peak, dominated by S. pilchardus and Micromesistius poutassou, was recorded in late winter at Stns 2 and 3. This pattern was evident for the three-year study. Results also indicate that this study was limited to the coastal larval fish assemblage inhabiting the central Cantabrian Sea shelf. This assemblage was temporally structured into other three assemblages: winter, late winter–spring and summer–autumn. Temperature was apparently a key factor in larval fish assemblage succession. In a scenario of global warming, this study constitutes a basis to evaluating the ongoing changes in the pelagic coastal ecosystem of the central Cantabrian Sea.  相似文献   

16.
《Journal of Sea Research》2007,57(2-3):198-208
Dover sole (Microstomus pacificus) and rex sole (Glyptocephalus zachirus) are both commercially valuable, long-lived pleuronectids that are distributed widely throughout the North Pacific. While their ecology and life cycle have been described for southern stocks, few investigations have focused on these species at higher latitudes. We synthesized historical research survey data among critical developmental stages to determine the distribution of life cycle stages for both species in the northern Gulf of Alaska (GOA). Bottom trawl survey data from 1953 to 2004 (25 519 trawls) were used to characterize adult distribution during the non-spawning and spawning seasons, ichthyoplankton data from 1972 to 2003 (10 776 tows) were used to determine the spatial and vertical distribution of eggs and larvae, and small-meshed shrimp trawl survey data from 1972 to 2004 (6536 trawls) were used to characterize areas utilized by immature stages. During the non-spawning season, adult Dover sole and rex sole were widely distributed from the inner shelf to outer slope. While both species concentrated on the continental slope to spawn, Dover sole spawning areas were more geographically specific than rex sole. Although spawned in deep water, eggs of both species were found in surface waters near spawning areas. Dover sole larvae did not appear to have an organized migration from offshore spawning grounds toward coastal nursery areas, and our data indicated facultative settling to their juvenile habitat in winter. Rex sole larvae progressively moved cross-shelf toward shore as they grew from April to September, and larvae presumably settled in coastal nursery areas in the autumn. In contrast with studies in the southern end of their range, we found no evidence in the GOA that Dover or rex sole have pelagic larval stages longer than nine months; however, more sampling for large larvae is needed in winter offshore of the continental shelf as well as sampling for newly settled larvae over the shelf to verify an abbreviated pelagic larval stage for both species at the northern end of their range.  相似文献   

17.
The ichthyofauna of the intermittently open Shellharbour Lagoon in southeastern Australia was sampled over 14 months to investigate factors influencing species composition. Zostera capricorni and bare sand habitats were sampled every two months with a fine-mesh seine. Of the 10 277 fish caught representing 19 families and 27 species, the most numerically dominant species were Pseudogobius olorum and Pseudomugil signifer. The most abundant economically important species were Acanthopagrus australis, Mugil cephalus and Myxus elongatus. Mean number of fish and species was significantly higher over Zostera than bare sand during months immediately after the estuary opened when juvenile marine fishes recruited, demonstrating the estuary's nursery function. In contrast to other intermittently open estuaries in Australia and South Africa, Shellharbour Lagoon's fish assemblage appears resilient to perturbation and does not undergo distinct seasonal variations. This may be a result of the estuary's short open phases providing less opportunity for marine fishes to enter. Perhaps more importantly, the less dramatic fluctuations in salinity between open and closed phases maintains salinity at a level intermediate of the tolerances of both marine and estuarine fishes.  相似文献   

18.
Brood sizes of 1259 adult female Euphausia pacifica and Thysanoessa spinifera were measured during 48 h incubations (10 °C, ±0.5 °C) on 27 oceanographic cruises between July 1999 and September 2004. The data set includes measurements from several stations off Newport, Oregon (Newport Hydrographic line, 44°39′N) made over a 5-year period and measurements from 14 more extensive cruises at stations representative of continental shelf, slope, and oceanic waters off Oregon and California, USA. E. pacifica had similar brood sizes at inshore (<200 m) and offshore (>200 m) stations with an average of 151 and 139 eggs brood−1 fem−1, respectively. T. spinifera brood sizes were considerably higher at inshore stations—particularly at Heceta Bank (44°N) and south of Cape Blanco (42°50′N)—than at offshore stations, 155 and 107 eggs brood−1 fem−1, respectively. Average brood sizes of E. pacifica increased during the study period, from 125 (in 2000) to 171 eggs brood−1 fem−1 (in 2003). Average percentage of carbon weight invested in spawning (reproductive effort) was higher in E. pacifica (14%) than in T. spinifera (6%), because both species have similar brood size but T. spinifera females are larger than E. pacifica females and produce smaller eggs. Reproductive effort for both species was higher during summer 2002, probably associated with anomalous cool subarctic waters and high chl-a concentration observed during that summer. Brood sizes and chl-a values remained relatively high in 2003–2004 compared to the 1999–2001 period. Geographical and temporal variability in brood sizes for both species were significantly correlated with in situ measurements of chl-a concentration but not with sea surface temperature. No gravid females were collected during late autumn and winter cruises, thus the spawning season along the Oregon coast appears to extend from March through September for both species. However, T. spinifera usually starts reproductive activity earlier in the spring (March) than E. pacifica. Both species had their highest brood sizes in summer during the period of most intense upwelling, which is associated with an increase in regional phytoplankton standing stock.  相似文献   

19.
浙江沿岸海域是日本鲐（Scomber japonicus）的重要产卵场。当前针对日本鲐幼鱼生长发育的研究较少,而环境因子会对其生长、分布造成较大影响。根据2019年5月的科学观察员取样数据和环境数据,对其群体组成进行研究,运用Pearson相关性分析、广义加性模型（GAM）探究其分布及个体大小的影响因子,利用克里金插值法定量分析溶解氧对日本鲐幼鱼分布影响。结果表明：海水表层盐度（Sea Surface Salinity,SSS）是影响日本鲐幼鱼分布的主要环境因子,幼鱼集中分布于27.5-27.8盐度海域;浙江沿岸南部海域日本鲐幼鱼叉长、体重均值分别为37.6 mm、0.659 g,中部海域叉长、体重均值分别为64.2 mm、3.305 g,南部、中部海域间鲐幼鱼大小存在显著性差异（P<0.05）;日本鲐幼鱼个体大小主要受溶解氧和纬度影响,个体大小与溶解氧呈多波峰的非线性关系,随纬度增加呈先减小再增大趋势。研究表明：溶解氧是影响浙江沿岸日本鲐幼鱼生长、分布的关键环境因子;结合幼鱼分布特征及个体大小差异,推测浙江沿岸海域日本鲐幼鱼来自不同产卵批次。  相似文献   

20.
凯伦藻属种类广布于世界沿海海域甚至大洋，属广域分布种。该属下多个种类曾在全球近岸海域暴发有毒有害赤潮，造成巨大的经济损失，其中不乏由多种凯伦藻同时混合形成赤潮的现象存在。在2016年香港海域的一次凯伦藻赤潮中，本团队从赤潮海水中分离出了米氏凯伦藻（Karenia mikimotoi）、长沟凯伦藻（K.longicanalis）、鞍形凯伦藻（K.selliformis）和蝶形凯伦藻（K.papilionacea）4种凯伦藻。本研究以此4种凯伦藻进行单种藻及多种藻混合样品的培养和溶血活性研究，以探究复合型凯伦藻的种间作用及溶血活性。结果表明，4种凯伦藻间存在种间相互作用，长沟凯伦藻会促进蝶形凯伦藻的生长，鞍形凯伦藻和米氏凯伦藻会抑制长沟凯伦藻生长。4种凯伦藻对兔血红细胞均有明显溶血活性，长沟凯伦藻溶血活性最强为46.36%±1.02%。每种凯伦藻与其他凯伦藻混合培养3天后，对兔血的溶血活性会明显增加，其中含4种凯伦藻的混合组溶血活性最高，为57.05%±1.13%。  相似文献   

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