Dynamics of Fish Colonization of an Experimental Artificial Reef in Peter the Great Bay,Sea of Japan

An experimental artificial reef (AR) was built in Peter the Great Bay (Sea of Japan) to compensate for the biotope of Zostera destroyed by sea urchins. After eight years, the number of fish species on the AR increased from 5 to 18 and the fish biomass increased from 3.07 up to 37.1 g/m². Nonmigrating species (Opisthocentrus, young-of-the-year rockfishes, elegant sculpin) formed the bulk of the population; and migrant species (flounders, frog and great sculpins, sea raven) made up the greater portion of the biomass (up to 34 g/m²). Cage reefs are recommended to compensate for destroyed habitats, particularly Zostera beds.Original Russian Text Copyright ¢ 2005 by Biologiya Morya, Markevich.     

Distribution and ecology of the tintinnids in the Gulf of Elat (Aqaba), Red Sea

The tintinnids were studied as part of a microplankton investigationin the Gulf of Elat (Aqaba) (Red Sea) based on stratified samplescollected at a reference station over a period of one year (1974–75).The results of this study were compared to the data obtainedfrom the same area in the course of a previous survey (1970–71). The ranges of abundance of the tintinnids as a whole and ofthe leading species of this group were determined from 0–50m, 50–100 m and thereafter at intervals of 100 m downto a depth of 600 m for the samples collected during 1974–75.For those collected during 1970–71, the ranges of abundancewere determined at two depths in vertical profiles over thewater column from 50 and 200 m to the surface. Two distinct peaks were noted, one in November-December anda second in February-March. A third minor peak occurred duringJune-July. The main winter peak of February-March occurred duringthe turnover period characterized by two uniform temperaturesof 21°C or less throughout the water column. The seasonaland spatial distribution of the tintinnids closely followedthat of the main phytoplankton groups, with greatest abundancerecorded in the upper 100 m. The species composition of the tintinnids during the annualpeaks changed from season to season and from year to year. However,8 species of a total of 42 recorded during the investigationwere responsible for the annual peaks during both years. Amongthe environmental parameters monitored during the 1974–75survey only the temperature factor could be related to the distributionpattern of one of the 8 leading species of tintinnids. A summer submergence to deeper levels has been noted in regardto some of the prevailing species.     

Colonization of an artificial stream by fishes and aquatic macro-invertebrates

We examined colonization by fishes and macro-invertebrates from permanent streams into an artificial freshwater stream simulating lotic temporary bodies of water that exist for only a limited period each year. After introducing water, invertebrates such as chironomid larvae in mud increased in numbers rapidly in the experimental stream, although they were rare in mud in the permanent streams. Eleven of 12 fish species present in the permanent streams colonized the experimental stream and preyed upon invertebrates, although fish composition differed significantly between the two streams. About 100 days after the initiation of the experiment, both species richness and diversity in the experimental stream reached almost the same level as that in the permanent streams. More diverse fishes colonized the complex section where habitat diversity was high compared to the simple section in the experimental stream. Our study strongly suggests that lotic temporary waters such as temporary streams around main rivers have unique ecological characteristics and serve as valuable foraging sites for fish.     

Community structure of the deep sea fishes in the northern Gulf of Aqaba,Red Sea (Osteichthyes and Chondrichthyes)

The aim of this study was to investigate the community structure of deep sea fishes in the northern Gulf of Aqaba. Deep fish traps, short lines and long lines were deployed at depth ranges from 60 to 700 m between June 2014 and May 2015. A total of 369 fish individuals belonging to 37 species in 21 families were collected. The most abundant family observed in deep fish traps and short line was the commercially important family Sparidae, whereas the most abundant family in long line catch was the commercially unimportant fish family Muraenidae. The most abundant fish species sampled by deep fish traps and shortline was Blueskin Seabream, Polysteganus coeruleopunctatus. The most abundant species in long line catch White-spotted Moray, Gymnothorax johnsoni. In fish traps and with short line, the most commonly caught species was Blueskin Seabream. White-spotted Moray was the most common long line catch. Depth distribution for 37 deep fish species and GIS maps for the two main commercial fish species Blueskin Seabream and Bigeye Hound Shark, Iago omanensis were documented.     

In situ nitrogen fixation associated with seagrasses in the Gulf of Elat (Red Sea)

In situ nitrogen fixation associated with the seagrass Halophila stipulacea, at the northern Gulf of Elat (Red Sea), is eight to ten times higher than that of nearby plant-free areas. A daily cycle of nitrogen fixation is evident, with rates during the day being seven times greater than during the night. Removal of seagrass leaves only from a patch within a seagrass bed gradually decreases nitrogen fixation activity, reaching the rates of plant-free areas after ten hours. A method devised for the in situ measurement of nitrogen fixation rates using belljars is described in detail. Nitrogen fixation rates in situ are higher than in the laboratory and lack the lag period typical to laboratory measurements. In laboratory experiments using intact plant samples, glucose enhances nitrogen fixation rates both in light and dark. Photosystem II inhibitor (3-3,4-dichloro-phenyl-1,1-dimethylurea) doubles nitrogen fixation rates in light. Both field and laboratory results indicate that light is essential for nitrogen fixation activity in the H. stipulacea bed possibly through its effect on cyanobacterial population that occupy the aerobic niches of the phyllosphere and on photosynthetic Rhodospirillacean bacteria that inhabit the anaerobic ones. Nitrogen fixation rates evident in H. stipulacea beds in situ account for a considerable portion of the biomass production by the seagrasses. The dependence of high nitrogenase activity by the diazotrophs on the presence of the seagrasses indicates the great importance of the seagrass community to the nitrogen cycle in its highly oligotrophic surroundings of the Gulf of Elat.     

Notes on primary productivity of coastal waters in the Gulf of Elat (Red Sea)

The following parameters were measured during May 1976 along the coasts of the Gulf of Elat (or: Gulf of Aqaba): phytoplankton species composition, chlorophyll content and photosynthetic production; weight of suspended particles and nutrient concentration; chlorophyll content of the sediments. The study areas were coral reefs of the northern part of the Gulf and a mangrove pool south of it. Phytoplankton characteristics and nutrient levels are those of oligotrophic waters. However, the sediments harbour such an abundant plant biomass that in coastal waters per m² surface area, there is several hundred times more chlorophyll in the sand than in the plankton. Reasons why both the mangrove and the coral reef may exhibit the same trends are discussed.     

西沙群岛主要岛礁鱼类物种多样性及其群落格局

为了解珊瑚礁海域鱼类物种多样性及其群落特征,作者2003年5月在西沙群岛7座主要岛礁(北礁、华光礁、金银岛、东岛、浪花礁、玉琢礁和永兴岛)采用底层刺网进行了调查,运用聚类分析和非度量多维标度(NMDS)等多元统计分析方法,对7个岛礁鱼类的种类组成、优势种、多样性和群落格局进行了分析.调查海域共记录鱼类146种,隶属10...     

The Influence of Habitat Complexity on Reef Fish Communities in the Northeastern Gulf of Mexico

Several previous studies have attempted to correlate habitat complexity and reef fish species diversity. These studies have mostly examined natural reef systems, but results differed. To examine this relation, we built 1 m² habitats with 20 replicates of five complexity levels from July to August 2001 in the northeastern Gulf of Mexico (n=100). In June and July 2002, we built new habitats using the 2001 design, but also added a sixth complexity level (n=120). In order of increasing complexity these included: cage, shell, cage-shell, block-shell, cage-block-shell, and shell-block-pyramid habitats. Most fish in both years were juveniles and included species common to reef structures in the northeastern Gulf of Mexico. In 2001, we identified 26 fish species, and the dominant species was red snapper, Lutjanus campechanus (41%), followed by rock sea bass, Centropristis philadelphica (23%), and sand perch, Diplectrum spp. (14%). In 2002 we identified 36 species, and the dominant species was tomtate, Haemulon aurolineatum (36%), followed by Diplectrum spp. (19%), and L. campechanus (13%). In 2001, species diversity and richness were significantly (P<0.05) higher on more complex habitats (H′=1.7, S=11–12) compared to less complex habitats (H′=0.8–1.0, S=4–9). In 2002, patterns among diversity, richness and reef complexity were less apparent with only the least complex habitats shell and cage showing significantly lower values. In both years, multidimensional scaling grouped by complexity levels with cage and shell habitats showing the clearest separation from other habitat types. Also, with few exceptions (only 8%) analysis of similarities showed significant (P<0.05) differences in fish communities across complexity levels. Although community composition varied between years, this study provided evidence to support the hypothesis that habitat complexity increased reef fish species diversity.     

Diversity,habitats and size-frequency distribution of the gastropod genus Conus at Dahab in the Gulf of Aqaba,Northern Red Sea

Topographically complex subtidal reefs of the Indo-West Pacific region are characterised by a high species richness of cone snails of the genus Conus (up to 36 on some reefs) but low population densities (≤1 individual/m²), whereas Conus assemblages on reef flats usually support fewer species (5–9) and high population densities (up to 5.2 individuals/m²). Subtidal sand areas are known to be least species-rich (1–6 species). Although the diversity of this predatory gastropod genus has been described previously from different areas of the Indo-Pacific, little ecological information is available on Conus in the Northern Red Sea. Therefore, data from five habitat types were obtained along 73 line-transects (245?m²⁾, which yielded ecological data for a total of 175 individuals of 9 species. In accordance with former findings, our results demonstrate that the reef flat was the habitat with the highest observed population densities (6.15 individuals/m²) but low species diversity (H’ = 0.9; 5 species); subtidal reefs, in contrast, were characterised by low densities (0.13 individuals/m²) and a relatively high species diversity (H ‘= 1.5; 6 species). This suggests that Conus diversity and species richness in the Northern Red Sea around Dahab is lower than in other parts of the Indo-West Pacific region. Furthermore, hardand soft substrata were dominated by different Conus species in accordance to the distribution of favourable microhabitat patches, the degree of physical stress and the availability of refuges and prey organisms. The fact that these Conus were predominantly small-bodied vermivores (size range: 6–85?mm; mean shell size: 15?mm; SD = 9?mm) suggests that this size class possesses an advantage over molluscivores and piscivores. Except for subtidal reefs, which showed a highly variable species composition, the studied habitat types around Dahab were characterised by distinct assemblages of Conus.     

The zonation of Tetrachthamalus oblitteratus Newman,and Tetraclita squamosa rufotincta Pilsbry in the Gulf of Elat,Red Sea

The zonation of barnacles on rocky shores along the northern 40 km of the eastern shore of the Gulf of Elat is described. Tetrachthamalus oblitteratus Newman, forms a wide belt in the midlittoral zone; Tetraclita squamosa rufotincta Pilsbry, forms a second barnacle zone which dissects the Tetrachthamalus belt and nearly obliterates it in its central portion. On south-facing slopes the Tetrachthamalus belt is more developed while the Tetraclita belt is reduced and found lower than on other slopes. On beachrock Tetraclita is found on rough surfaces or forms a rim on the margins of crevices and ledges. It is concluded that Tetraclita is favoured by turbulence and wave action. It is suggested that Tetraclita and Tetrachthamalus compete in the main part of the midlittoral and that Tetrachthamalus is more tolerant to heat and desiccation than Tetraclita.     

Fish larvae assemblages in the Gulf of California

The distributional diversity and assemblages of fish larvae in the Gulf of California indicated two main seasonal stages and two transitional periods: in winter, the tropical water mass is confined to the south‐east portion of the mouth of the Gulf and larval fish assemblages are dominated by subtropical and temperate‐subarctic species; in summer; tropical water invades the Gulf and assemblages are dominated by tropical species. Both seasonal stages are separated by transitional periods coinciding with strong latitudinal temperature gradients. During the autumn and spring transitional periods, the Gulf of California splits into three regions: a northern region where temperate and subarctic species spawn from autumn to spring, a southern region dominated by tropical and subtropical species year round and a central region where tropical and temperate assemblages merge. Seasonal changes in the location of the regions, as well as the borders between them, show expansion and contraction of the northern and southern faunas related to the general oceanic circulation patterns during the year.     

Community Structure of Macrobenthic Invertebrates in Sandy Beaches of the Jordan Gulf of Aqaba,Red Sea

Six sandy beach stations along the Jordan Gulf of Aqaba were selected for macrofaunal examination during November 1980. Fifteen core samples (0.01 m² to a depth of 10–15 cm) were taken at each station; five at the high tide line, five at the low tide line, and five midway. Twenty-two taxa were encountered from all stations. Polychaetes were the most diverse group with seven taxa, followed by molluscs and crustaceans with six and five taxa respectively. Animal diversity, using the Shannon-Wiener Index, was generally low. Based on the biological index value of McCLOSKEY (1970), seven taxa were considered the community dominants. These are: the polychaetes, Glycera tesselata, Pisione remota, Saccocirrus sp., and Perinereis nuntia; the isopod Eurydice arabica; a nemertean and an oligochaete.     

Seasonal and Geographic Distribution of Luminous Bacteria in the Eastern Mediterranean Sea and the Gulf of Elat

Luminous bacteria in the Mediterranean Sea and the Gulf of Aqaba-Elat have different distribution patterns. In the Mediterranean Sea, Beneckea harveyi is present all year round, with different subtypes alternating in summer and winter; Photobacterium fischeri was only present during the winter. In the Gulf of Elat, P. leiognathi is present throughout the water column in similar densities during the entire year. This constancy in distribution is presumably due to the near-constancy in water temperature. In summer, Photobacterium leiognathi is replaced by B. harveyi in coastal surface waters. In the hypersaline Bardawil lagoon, only B. harveyi types are present. P. fischeri, a major component of the Mediterranean Sea winter communities, is absent from the lagoon. Luminous Beneckea strains show a great diversity in properties, e.g. temperature range for growth, sensitivity to infection by phages, sensitivity to attack by Bdellovibrio strains, and differences in tolerance to high-salinity shock. Therefore, subdivision of the taxonomic cluster of B. harveyi into subtypes is indicated. The composition of the luminous bacteria communities may serve as indicators of different marine water bodies. The symbiotic luminous bacteria of the light organ of the common Gulf of Elat fish, Photoblepharon palbebratus steinitzi, is different from any of the types described.     

Ecological assessment of finfish as indicators of habitats in the Gulf of Nicoya,Costa Rica

Trawl samples of demersal fish populations within the Gulf of Nicoya, Costa Rica were conducted during February and July, 1979 and April, 1980 in an attempt to define basic abundance, diversity and distributional patterns. Seventeen day and three night samples produced 6 441 fishes of 107 species during the February cruise. Twenty day and two night samples produced 9 220 individuals of 131 species during the July cruise. Twenty day samples produced 14 151 individuals representing 125 species taken during the April cruise. A total of 214 species were collected during this study.The Gulf may be divided into three zones on the basis of the physical characteristics of the stations (water temperature, dissolved oxygen, salinity, depth and distance from the mouth of the Gulf). Few changes in the position of these zones occurred during the study period indicating a relatively stable estuarine configuration from a biological perspective.The Gulf of Nicoya area is under the influence of a wet and a dry season. No significant seasonal changes in the number, biomass, percent occurrence, diversity of partitioning by size class of fishes were observed.Two major types of fish distributional patterns were observed. Several species were ubiquitous and were found throughout the Gulf in varying abundances. Other species were restricted to either the upper or lower Gulf. Dominant groups in the upper Gulf include the sciaenids, sea catfishes (Ariidae) and flatfishes (Soleidae, Cynoglossidae andSyacium ovale). These fishes tend to inhabit the warmer, shallower, less saline waters of the upper Gulf. Flounders (bothidae), gobies (Bollmannia spp.), morays and congers (Hildebrandia nitens, Priodonophus equatorialis andMuraenesox coniceps) and several other species dominated the deeper, cooler, more saline lower Gulf.     

宁夏沙坡头自然保护区鱼类多样性

1998~1999年和2002~2004年对宁夏沙坡头自然保护区的鱼类进行调查,经鉴定有鱼类18种,隶属3目5科17属,鲤形目占83.33%。其中人工养殖的有4种,鳙(Aristichthys nobilis)、鲢(Hypophtlmichthysmolitrix)、草鱼(Ctenopryngodon idellus)和团头鲂(Megalobrara amblycephola)。沙坡头地区的野生鱼类种类较少,但组成复杂,由江河平原、古代第三纪、北方平原、中亚山地和印度平原5个鱼类区系复合体组成,其中以江河平原复合体和古代第三纪复合体为主。沙坡头鱼类组成的复杂原因主要是:(1)养渔业的干扰;(2)保护区的地理位置;(3)历史因素。     

Colonization,diversity, and seasonality of fishes at pelagic fish aggregating devices

The pelagic zone of the ocean can be a challenging environment in which to conduct research and as a result we lack the robust baseline abundance and diversity data, compared to what is available in more accessible coastal habitats, to be able to track changes or stressors to the biota in this environment. Many large-scale fisheries target pelagic fish, and much of the information available on these species is based on fisheries-dependent data that may be biased towards hotspots and commercially valuable fishes. Here, a long-term video and visual fish survey was conducted on two subsurface moored fish aggregating devices (FADs) in the pelagic waters of the central Bahamas to determine the feasibility of using moored pelagic FADs as tools for collecting fish abundance and diversity data. A wide range of species was documented, including large migratory fish that are the focus of commercial and recreational fisheries, and smaller often overlooked species on which little abundance or seasonality information exists. We found that FADs colonize quickly and reach a peak stable (albeit seasonally cyclical) abundance and diversity within the first several months after deployment. Species richness was higher in video surveys, but abundance was higher in visual surveys, except for sharks. Our results highlight the need to tailor survey methods to fit the context and study objective, and provide further evidence for the importance of fisheries-independent data in monitoring pelagic species.     

Comparison of Fish Assemblage Diversity in Natural and Artificial Rip‐Rap Habitats in the Littoral Zone of a Large River (River Danube,Hungary)

We studied day‐night patterns in fish diversity in natural, gravel‐sand stretches and boulder covered rip‐rap habitats in the littoral zone of the River Danube. Sample‐based rarefaction indicated marked differences in species richness between day and night, and smaller differences between habitats for both day and night. Whereas, individual‐based rarefaction indicated no such substantial differences in species richness. However, distinct fish assemblages were found based on relative abundance data, and species of great conservation concern tended to link to natural habitats. The diversity of biological traits/attributes were generally higher in rip‐rap habitats. The differences in fish assemblage characteristics between habitats revealed the importance of gravel‐sand habitats in maintaining natural assemblages and that rip‐rap sections increase compositional beta diversity at the mesohabitat scale. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Physiological Characteristics Underlying the Distribution Patterns of Luminous Bacteria in the Mediterranean Sea and the Gulf of Elat

Physiological characteristics of luminous bacteria isolated from the Mediterranean and Gulf of Elat were compared to determine their relationship to the specific seasonal and geographic distribution patterns of these bacteria. The effects of temperature on growth rate and yield, relative sensitivity to photooxidation, resistance to high salt concentration (8%), and ability to grow in nutrient-poor conditions appear to control these patterns. The winter appearance of Photobacterium fischeri and the succession of winter and summer types of Beneckea harveyi in the eastern Mediterranean are explained by different temperature requirements for growth. Sensitivity to photooxidation explains the disappearance of P. leiognathi, present in the main body of the Gulf of Elat throughout the year, from the shallow coastal strip. B. harveyi is present in this coastal strip which is higher in nutrients and in productivity than the open waters. Competition experiments between B. harveyi and P. leiognathi in batch and continuous culture indicate that the oligotrophic P. leiognathi is outcompeted by B. harveyi in rich and even in relatively poor media. The distribution pattern found in the Bardawil hypersaline lagoon is explained by selection of salinity-resistant mutants of B. harveyi from the Mediterranean Sea.     

南海西北部陆架区鱼类的种类组成与群落格局

根据2006-2007年在南海西北部陆架区海域进行的4航次底拖网调查数据,对该海域鱼类的种类组成和群落格局进行分析.调查共采获鱼类262种,隶属于20目102科.以冬季出现种类数最多,为166种;夏季和秋季次之,分别为161种和155种;春季最少,为135种.运用聚类分析和非度量多维标度(NMDS)方法分析了南海西北部陆架区鱼类群落结构的空间分布.研究表明,该海域鱼类可划分为5个群落,分别为粤西沿岸群落(群落Ⅰ)、海南岛东南沿岸群落(群落Ⅱ)、海南岛东部深海群落(群落Ⅲ)、过渡群落(群落Ⅳ)和混合群落(群落Ⅴ).ANOSIM检验表明,各群落间鱼类组成的差异极为显著(R=0.847-0.939,P＜0.001).鱼类群落格局的变化与海流和水深关系密切,有较明显的沿水深梯度分布的规律.咸淡水鱼类在雷州半岛东部的冷涡区域,形成群落Ⅰ;南海暖流控制区域内的深海鱼类,形成群落Ⅲ;在南海暖流最为强劲的冬季,研究区域内大部分鱼类集结为混合性群落Ⅴ;琼东南沿岸的上升流区内形成群落Ⅱ;沿岸流强劲的夏、秋季,在沿岸流和上升流交汇处,形成过渡性群落Ⅳ.     

Seasonal dynamics of phytoplankton in the Gulf of Aqaba,Red Sea

Seawater samples were collected biweekly from the northern Gulf of Aqaba, Red Sea, for Phytoplankton analysis during the period May 1998 to October 1999. Microscopic counts and HPLC methods were employed. Procaryotic and eucaryotic ultraplankton dominated throughout most of the year, with larger nano- and microplankton making up only 5% of the photosynthetic biomass. Moderate seasonal variations in the 0–125 m integrated Chl a contrasted with a pronounced seasonal succession of the major taxonomic groups, reflecting the changes in the density stratification of the water column: Prochlorococcus dominated during the stratified summer period and were almost absent in winter. Chlorophyceae and Cryptophyceae were dominant during winter mixing but scarce or absent during summer. Diatoms and Synechococcus showed sharp and moderate biomass peaks in late winter and spring respectively, but remained at only low Chl a levels for the rest of the year. Chrysophyceae, Prymnesiophyceae and the scarce Dinophyceae showed no clear seasonal distribution pattern. The implications of alternating procaryotic and eucaryote dominated algal communities for the Red Sea pelagic food web are discussed. Electronic Supplementary Material Electronic supplementary material is available for this article at and accessible for authorised users.