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Pietro Franco, HongJu Chen, and Jiang Shiou Hwang (2016) The ecological importance of pelagic tunicates and their role in marine ecosystems are receiving increasing attention, especially with respect of their role in the carbon flow through the planktonic food web and their fundamental influence on the microbial food web. Nuclear Power Plants I and II are located in most populated northern Taiwan. Effects of the discharge of the cooling water from nuclear power plants have drawn great attention since 1977. No studies on pelagic tunicates were carried out in the area. Taxonomic composition, distribution, abundance and seasonality of pelagic tunicates belonging to the two taxonomic classes Larvacea and Thaliacea were studied and their relationship with environmental conditions were analyzed from 21 stations in the waters adjacent to 2 nuclear power plants in northern Taiwan. A total of nine species were identified: the appendicularians Oikopleura dioica, O. caphocera, O. rufuscens, O. longicauda, Fritillaria aberrans and the thaliaceans Doliolum denticulatum, Thalia democratica orientalis, Dolioletta gegenbauri and Thetys vagina. There is a strong seasonality in the area. In fact, the highest abundances were measured during the summer season, whereas low abundances prevailed in the rest of the year. No relationship was found between tunicate abundance and surface temperature and salinity, likely due to slight changes of the two environmental parameters of the studied area within each season. The hypothesis regarding a direct effect of the discharged cooling waters on the organisms was consequently discarded. The abundances of larvaceans and thaliaceans were significantly influenced by the concentration of chl-a, among the four seasons as well as within all the stations for each season.There is a strong seasonality in the area concerning the distribution and abundance values of the nine species of pelagic tunicates in the area.The presence of the organisms is more influenced by the availability of food during the four seasons rather than by the effects of the discharged waters from the two nuclear plants. Further research needs to describe inter-annual changes in seasonality of pelagic tunicates in this area.

Parinya Limviriyakul, Li-Chun Tseng, Jiang-Shiou Hwang, and Tung-Wei Shih (2016) Symbiotic anomuran and brachyuran crabs were identified after extensive surveys of reef zones, especially from sponges, scleractinian corals, crinoids, and sea urchins, in the coastal areas of the southern East China Sea. Twenty-nine species belonging to 17 genera, 9 families, and 2 infraorders were identified (3 were identified to the generic level). More crabs belonged to the infraorder Brachyura (82.8%) than to Anomura (17.2%). Two anomuran symbionts (Allogalathea elegans and Petrolisthes virgatus) and 5 brachyuran symbionts (Tetralia glaberrima, Tetralia rubridactyla, Trapezia cymodoce, Trapezia septata, and Cymo melanodactylus) are common in this area. Two species of Anomura (Lauriea simulata, Petrolisthes virgatus) and 3 of Brachyura (Gonatonotus nasutus, Tetralia aurantistellata and Tetralia nigrolineata) were identified for the first time from waters adjacent to Taiwan. These records represent the northernmost recorded of L. simulata and T. aurantistellata. The occurrence of P. virgatus is the second in the western Pacific Ocean. This study revealed the geospatial distribution of symbiotic crabs, which connects the region from the southern Ryukyu arc to the Coral Triangle, and provides the supporting taxonomic account of symbiotic anomuran and brachyuran crab fauna inhabiting the reef zone in northern Taiwan

Background It is controversial to what extent the intrusion of the Kuroshio Branch Current to the Luzon Strait and the South China Sea circulation can shape copepod assemblages around southern Taiwan. We tested the hypothesis that currents such as the Kuroshio Current bring marine zooplankton and copepods from subtropical and tropical waters to the south of Taiwan. We studied copepod assemblages from the Bashi Channel in the northeastern South China Sea at the coast of southwest Taiwan during early October 1996. Results A total of 77 copepod species were identified from 34 genera that included calanoids, cyclopoids, harpacticoids, and poecilostomatoids. Several indicator species suggest that the study area is highly influenced by water masses from the northern South China Sea as well as from the Kuroshio Current. Acrocalanus gracilis (Paracalanidae, Calanoida) was most abundant (with a relative abundance (RA) of 22.07 and an occurrence rate (OR) of 100%), followed by Paracalanus aculeatus (Paracalanidae, Calanoida) and Oncaea venusta (Cyclopoida). The stations close to the Kuroshio Current showed a higher species diversity (H') and a higher species richness with 3.9 to 4.6 at moderate abundance, whereas station 11 showed lowest species diversity (H') with (2.1), accompanied by the far lowest species number (14) and abundance (880 ind./100 m3). Conclusions Several indicator species suggest that the study area is highly influenced by water masses from the northern South China Sea as well as from the Kuroshio Current.

Anissa Souissi, Sami Souissi, and Jiang-Shiou Hwang (2016) Zooplankton and particularly copepods have a key role in the functioning of aquatic ecosystems. However, the mechanisms involved in the physiological responses of copepods to temperature and salinity increases are little understood, and the role of plasticity involved in facing environmental changes has rarely been demonstrated experimentally. In this study, the copepod Eurytemora affinis, widely distributed in the northern hemisphere, was selected as a biological model to test the effect of a 4°C temperature increase at two salinities. In addition to the optimal salinity (15 psu), a stressful condition of salinity 25 psu was also verified. Copepods from the Seine estuary were acclimated in laboratory to their optimal temperature of 15°C at salinity 15 PSU and then they were acclimated during several generations to their upper thermal limit (20°C) at two salinities (15 and 25 PSU), after which the temperature was raised by 4°C. This experiment revealed that after long-term acclimation and under unlimited food conditions, E. affinis maintained good fitness at 20°C and at both optimal and stressful salinities. After temperature increase to 24°C, the population remained viable but copepod size was significantly decreased as well as female’s fecundity. The decrease of fitness was accentuated under the additional stressful condition of salinity 25 psu. This study demonstrated that the mechanisms of response to temperature and salinity increases (i.e. global warming) are complex, and should be investigated through experimental studies that consider acclimation and multigenerational factors. Our results will enrich the development of Individual-Based Models (IBMs) capable to test the role of microevolution and plasticity of E. affinis in the framework of future climate scenarios.

Background Pseudodiaptomus annandalei is an estuarine species and being cultured as live feed for grouper fish larvae and other planktivores. We examined the predation behavior of P. annandalei adults when preying on ciliated protists (Euplotes sp.) and the effects of mono- and pluri-algal diets on ciliate predation by P. annandalei under laboratory conditions. The algal food comprised the pigmented flagellate Isochrysis galbana (4 ~ 5 μm) and Tetraselmis chui (17 ~ 20 μm). Results Males and females of P. annandalei consumed 8 ~ 15 ciliate cells/h. The probability of ciliate ingestion following an attack was a direct function of the copepod's hunger level. Conversely, the probability of prey rejection after capture was a negative function of the copepod's hunger level. Starved and poorly fed females showed a significantly lower rate of prey rejection compared to similarly treated males. The duration of handling a ciliate prey did not significantly differ between males and females of P. annandalei. Starved copepods spent less time handling a ciliate prey than fed copepods. Prey ingestion rates showed a negative relation with the feeding duration, whereas the prey rejection rate increased as the feeding duration increased. The ciliate consumption rate of P. annandalei was significantly lower in the presence of mixed algae. Neither I. galbana nor T. chui alone had any significant effect on ciliate consumption by P. annandalei. Conclusions The results confirmed that P. annandalei ingests bacterivorous heterotrophic protists even in the presence of autotrophic protists. Therefore, our results point to the role of P. annandalei in the transfer of microbial carbon to the classical food chain in estuarine and brackish water ecosystems.

Background For the present study, we collected mesozooplankton in the upper layer (above 100 m in depth) of four stations in the northern South China Sea (SCS) to determine the influence of different water masses on their distribution and abundance from 27 September to 2 October 1999. Results In total, 18 major zooplankton taxa were recovered from the samples. Calanoid copepods, Noctilucales, and chaetognaths were dominant and together comprised 65.90% of the overall zooplankton counts. Zooplankton densities ranged from 102.19 to 1,285.24 individuals per cubic meters (ind./m3) (average, 306.38 ± 435.71). Noctilucales were abundant at stations located in the Kuroshio Current (KC) intrusion area. Integrating all samples, 32 copepod species were identified consisting of 23 genera belonging to 16 families. Total copepod abundances ranged from 30.24 to 311.17 ind./m3 (average, 99.14 ± 97.84). Numerically, Pleuromamma gracilis, Nannocalanus minor, and Lucicutia flavicornis were the most dominant species. The most frequently occurring species in all samples were Acartia (Acartia) negligens and Corycaeus (Farranula) gibbula. Results of a cluster analysis indicated that community structures of zooplankton and copepods of the northern SCS varied at geospatial scales during the sampling period. Conclusions Results of the present study suggest that the composition and community structure of zooplankton and copepods were influenced by intrusion of the KC in the shallow layer above 100 m in depth in the northern SCS. Some indicator species characteristic of the KC indicated that the study area received water masses from the northern SCS and the KC.

BackgroundHydroids were identified from extensive surveys of benthos, and especially from worm tubes, in the Danshuei River estuary (DRE), in the northeast Taiwan Strait (NETS), and on a reef in Nanwan Bay (NWB), Taiwan.ResultsA total of 33 species (12 of them identified to generic and 1 to family rank only), referable to 22 genera, 12 families, and 2 orders, were distinguished. The majority of them were referable to order Leptothecata (84.8%) with the remainder being assigned to order Anthoathecata (15.2%). The only species found at NETS wasMonoserius pennarius(Linnaeus, 1758).Plumularia habereri(Stechow, 1909) was recorded at both DRE and NWB. The known range ofDynamena nanshaensis(Tang, 1991), recorded for the second time, is extended further north. Six species (Aglaophenia latecarinata,Plumularia floridana,Diphasia palmata,Dynamena brevis,Dynamena obliqua,Synthecium elegans) are recorded for the first time in waters adjacent to the Chinese mainland.ConclusionsSpecies composition and abundances varied considerably from one environment to another and especially between DRE and NWB. This study provides the first taxonomic account of the hydroid fauna inhabiting the eastern Taiwan Strait region.

Background The conservation effectiveness of marine protected areas is of substantial dispute. In the Belize Barrier Reef, there are several zones with increasing human activity and harvesting of overexploited species. Marine protected areas are designed to protect endangered species and increase the population size of exploited species. The present study investigated the population and morphological characteristics of Lobatus gigas (Linnaeus, 1758) in the Sapodilla Cayes Marine Reserve (SCMR) at the southernmost tip of the Belize Barrier Reef to estimate the effectiveness of the marine protected area. Results A total of 693 L. gigas conches were counted over the 7,200 m2 from 36 transect lines. The densities of juveniles and adult conches in the conservation zone were substantially higher (20.13 and 2.88 individuals/100 m2, respectively) than in the general use zone (5.29 juveniles and 0.58 adults individuals/100 m2). The shell length of adult individuals ranged from 14.4 to 18.5 cm in the conservation zone and from 14.6 to 18.1 cm in the general use zone. A comparison of shell length of juveniles and adults showed no significant differences between the conservation zone (11.39 ± 1.46 cm) and general use zone (11.62 ± 1.24 cm). There was a significant positive correlation for shell length with lip thickness in the conservation zone (Pearson's correlation, r = 0.729, p r = 0.613, p = 0.02). Conclusions The function and effectiveness of marine protected areas are discussed using the results of the present study that identifies the primary objective which is to ensure a continuous recruitment of valuable targeted species by the protection of spawning stock biomass that is important for the management of marine protected areas in an environmentally sensitive ecosystem.