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Thalia democratica Morphology Length of the aggregated zooids of this salp is 1.8–18.2 mm. Lengths of solitary zooids are 2.3–11.7 mm. Aggregate form is characterised by an anterior end of the body which is rounded and by a posterior end which is somewhat fusiform. Testis is never echinate, and is pentagonal. Nucleus with a posterior projection. Testis pentagonal posteriorly. Number of muscle fibres in MI–MV is15–17. Atrial opening not central, with a posterior lateral protuberance on one side only. Solitary forms with a smooth test and simple atrial palps. Lateral projections are small, medio-ventral ones are small and of unequal length and anterior projections are smallest. All test projections are echinate. MI to MIV are continuous dorsally and ventrally; MV is interrupted ventrally. MII –MIV and MV–MVI converge mid-dorsally over a short distance. Stomach extends partly into the middle posterior projection (authors’ personal observations; (Marine Species Identification Portal 2017); Godeaux et al. 1998). Biogeography Cosmopolitan, eurythermic species from warmer waters; roughly occurring between ca. 60°N and 40°S. Also present in the Mediterranean Sea. Epipelagic, living in the upper 100 m; does not perform diurnal vertical migration (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 930, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","Godeaux J, Bone Q, Braconnot JC. 1998. Anatomy of Thaliacea. In: Bone Q, editor. The biology of pelagic tunicates. Oxford: Oxford University Press; p. 2 - 24.","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Oikopleura (Coecaria) longicauda Morphology With a compact trunk up to 1.4 mm in length, with musculature in the broad tail. The post-cardial caecum joins the genital wall of the esophagus and points dorsally. The long velum extends dorsally over the oral part. The rectum is developed beyond the oral wall of the stomach. The gonads join the coil of the gut (Godeaux et al. 1998; authors’ personal observations). Biogeography A semi-cosmopolitan species in temperate to tropical waters (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 927, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Godeaux J, Bone Q, Braconnot JC. 1998. Anatomy of Thaliacea. In: Bone Q, editor. The biology of pelagic tunicates. Oxford: Oxford University Press; p. 2 - 24.","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Oikopleura intermedia Morphology The trunk is up to 2.5 mm long. Musculature of the tail is wide. A postcardial caecum is present dorso-genitally. There are wide bays between the genital parts of the left and right lobes of the stomach. The gonads are positioned next to the stomach lobes and the rectum extends beyond the oral wall of the stomach (authors’ personal observations (Marine Species Identification Portal 2017). Biogeography Recorded from Somalia, Mexico, the Mediterranean and the North Atlantic Ocean (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 928, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Dolioletta gegenbauri Morphology Carrying a small gonozooid (3–9 mm) with a delicate test. The intestine is dextrally coiled and the anus is in a median position. The testis forms an oblique line forward and upward and it extends forward towards the body cavity. The ovary is located ventrolaterally near MVII. The gills form several pairs. They attach anteriorly and dorsally behind MIII, extend rearwards, curve just before MVI and turn forwards to the attachment point at MV. Endostyle is long. Dorsal nerve ganglion is located just behind MIII. The anterior aperture is characterised by a 12-lobed fringe, and the posterior aperture by an eightlobed fringe (authors’ personal observations; Godeaux et al. 1998)). Biogeography Records exist from the central, northern and subtropical south Atlantic Ocean; tropical and temperate south-west Indian Ocean, tropical west and south-west Pacific Ocean; and the Mediterranean Sea (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 929, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Godeaux J, Bone Q, Braconnot JC. 1998. Anatomy of Thaliacea. In: Bone Q, editor. The biology of pelagic tunicates. Oxford: Oxford University Press; p. 2 - 24.","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Iasis cylindrica Morphology Body elongate and cylindrical and characterised by five body muscles, all of them meeting in the mid-dorsal region. Transverse ribs of gill bar meet dorsally and narrow towards the ventral surface. Solitary zooids measure up to 45 mm length with a soft test. Solitary forms have eight or nine separate muscles extending ventrally. MI to MIV are fused in the mid-dorsal line or converge. Aggregated zooids can measure up to 17 mm in length, and their body is fusiform because of the presence of short anterior and posterior projections (authors’ personal observations; Godeaux et al. 1998). Biogeography Recorded in the North Atlantic Ocean and Gulf of Mexico (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 931, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Godeaux J, Bone Q, Braconnot JC. 1998. Anatomy of Thaliacea. In: Bone Q, editor. The biology of pelagic tunicates. Oxford: Oxford University Press; p. 2 - 24.","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Ihlea punctata Morphology Aggregate form with a thin and fusiform test. Body shape oval to cylindrical. Aggregate form with two rows of pigment spots at each side, from the endostyle to the ventral body surface. Six muscle bands are continuous dorsally but interrupted ventrally. MI– MII unite mid-dorsally, making a group of four muscle bands with MIII and MIV. MV and MVI are united mid-dorsally as well. Ventrally, the muscle bands are asymmetrical. Distinct dextral and sinistral individuals depend on the same morphology. Intestine is coiled. Ovary and embryo are situated on right side between MV and MVI. Solitary form has a thin test which is loosely attached to the body wall. Nine wide body muscles cover almost the whole body. A variable number of body muscles fuse in the mid-dorsal region. Except MVIII all of them are completely continuous around the body. The dorsal tubercle is a short straight stick. The stolon is tightly coiled underneath the nucleus. The length of the aggregated form can be up to 23 mm and the length of the solitary form can reach up to 71 mm (authors’ personal observations; Marine Species Identification Portal 2017). Biogeography Cosmopolitan, eurythermal species of temperate and tropical waters, absent from the Red Sea and the subtropical South Pacific Ocean. Epipelagic, living between the surface and about 150 m water depth. It does not migrate vertically. Although Ihlea punctata has a wide distribution, it is one of the less common salpids (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on pages 932-933, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Franco, P., Dahms, H.-U., Lo, W.-T., Hwang, J.-S. (2017): Pelagic tunicates in the China Seas. Journal of Natural History 51 (15-16): 917-936, DOI: 10.1080/00222933.2017.1293180, URL: http://dx.doi.org/10.1080/00222933.2017.1293180

Cyclosalpa pinnata Morphology Solitary zooids up to 75 mm long with body muscles interrupted dorsally. Dorsal longitudinal muscles are absent. Five pairs of light organs present between MI and MVI. Aggregated zooids measure up to 64 mm in length. Body muscles are symmetrically arranged. MI and MII are fused dorsally; MIII and MIV are not contiguous dorsally but converge (authors’ personal observations; Marine Species Identification Portal 2017). Biogeography Records in the North Atlantic Ocean, North Pacific Ocean, Mediterranean (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 933, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Soestia zonaria Morphology Aggregate forms of this salp have a large, prismatic body and tough test. The body is posteriorly asymmetrical, with a deep groove both dorsally and ventrally. A single, acentric projection is present at the posterior end. Muscle bands are clear and wide and are all ventrally interrupted; only MI is also dorsally interrupted. MIV and MV are dorsally united. Solitary form with a large body, conspicuously prismatic; tough and firm test. Its muscle bands are extremely wide, almost touching each other laterally. Muscle bands are dorsally and ventrally interrupted. Posterior ends of body with marked pointed projection. The intestine is encircled by the stolon. Aggregate form is up to 60 mm in length. The solitary form is up to 50 mm in length (authors’ personal observations; Marine Species Identification Portal 2017). Biogeography Eurythermal species from all oceans except for the Southern and Arctic oceans (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 931, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Brooksia rostrata Morphology Solitary zooids measure up to 31 mm without the anterior projection. MI and intermediate muscle are contiguous or fused with MII and MIII in the mid-dorsal line (authors’ personal observations; Marine Species Identification Portal 2017). Biogeography Recorded in the Red Sea, Indo-West Pacific, and the Tropical Atlantic and North Atlantic Ocean (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 931, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Thalia orientalis Morphology Solitary zooids are up to 7 mm long, excluding posterior projections. Tests often with eight longitudinal rows of echinae on the surface. Long posterior projections, but lateral ones are absent and mid-ventral ones are strongly developed. Atrial palps are bifurcate. MI to MII are not contiguous, MII to MIII and MIV to MV are strongly fused dorsally. Total number of muscular fibres is 30–36, including the intermediate muscle (authors’ personal observations; Marine Species Identification Portal 2017). Biogeography The species is found in the Mediterranean Sea and China Seas (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 930, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Pegea confoederata Morphology Aggregates form with a loose flabby test. There are no posterior projections or protuberances. MI– MII and MIII–MIV touch or fuse mid-dorsally, each muscle pair forming a cross. Muscle bands are short and interrupted before they reach the mid-lateral region. Stomach is spherical. Solitary forms have a pear-shaped test. MI– MII and M3III–MIV touch or fuse, each pair forming a cross. Gut is compact and encircled by a stolon. The length of the aggregate form is up to 150 mm; the length of the solitary form is up to 120 mm (authors’ personal observations (Marine Species Identification Portal 2017). Biogeography Cosmopolitan, eurythermal species, occurring between ca. 60°N and 45°S. A common salp species. Living near the surface, epipelagic (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 932, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Doliolina muelleri Morphology Body length is about 4 mm. Gonozooid is small, with a U-shaped intestine. Gill slits are small, attaching ventrally and dorsally at MV; and slightly curved backwards reaching MVI. Spherical testis lies in a ventral pocket, slightly extruding from the body between MV and MVI. The frontal end of the endostyle is situated between MII and MIII; the caudal end is just situated in front of M5. The dorsal nerve ganglion is located between MIII and MIV (authors’ personal observations (Marine Species Identification Portal 2017). Biogeography Records are available from the central, northern and temperate south-east Atlantic Ocean, tropical and temperate south-west Indian Ocean, east central Pacific and Mediterranean Sea (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on pages 929-930, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Marine Species Identification Portal. 2017. ETI BioInformatics in the KeyToNature programme [Internet]. Available from: http: // species-identification. org /","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

Salpa fusiformis Morphology Solitary zooids are elongated, having a slightly convex anterior and a square shape cut off posteriorly. Test entirely smooth. Muscles (M)I–III are strongly fused over a broad area in the mid-dorsal region; M8 and M9 are also strongly fused. Dorsal tubercule is small and C-shaped. Nucleus is relatively small and compact. The aggregate zooids are characterised by a barrel-shaped body and typically fusiform with conical anterior and posterior protuberances of the test. Testes are elongated. Asymmetry of the body is a main characteristic. Test entirely smooth and thin. There are six body muscles; MI–MIV strongly fused over a wide area in the mid-dorsal region; MIV–MV fused laterally; MV– MVI strongly fused in the mid-dorsal region. Solitary zooids measure up to 22–52 mm, while the aggregated zooids are up to 7–52 mm long (excluding projections) (authors’ personal observations; Godeaux et al. 1998). Biogeography Cosmopolitan, eurythermal species, occurring from 70°N to 45°S in the Atlantic Ocean, to 45°S in the Indian Ocean and from 50°N to 45°S in the Pacific Ocean. S. fusiformis has got the widest distribution of all salp species, and it is also one of the most abundant species. Distributed from the surface to ca. 800 m depth; seems to perform diurnal vertical migration (WoRMS Editorial Board 2017)., Published as part of Franco, P., Dahms, H. - U., Lo, W. - T. & Hwang, J. - S., 2017, Pelagic tunicates in the China Seas, pp. 917-936 in Journal of Natural History 51 (15 - 16) on page 932, DOI: 10.1080/00222933.2017.1293180, http://zenodo.org/record/5180954, {"references":["Godeaux J, Bone Q, Braconnot JC. 1998. Anatomy of Thaliacea. In: Bone Q, editor. The biology of pelagic tunicates. Oxford: Oxford University Press; p. 2 - 24.","WoRMS Editorial Board. 2017. World Register of Marine Species [Internet]. Available from: http: // www. marinespecies. org at VLIZ. doi: 10.14284 / 170"]}

International audience; Estuarine waters contain a variety of chemicals which affect to various extents the behavior of aquatic organisms. Little is known, however, on the behavioral response of copepods. The present study shows the results of laboratory experiments investigating the immediate effects of sub-lethal concentrations of three commonly found contaminants on the three-dimensional swimming behavior of the estuarine calanoid copepod Eurytemora affinis. Nonylphenol at 2 μg L−1, cadmium at 45 ng L−1 and a mixture of low to medium molecular weight polycyclic aromatic hydrocarbons at 40 ng L−1 all affected the swimming behavior of E. affinis adults, increasing both swimming speed and activity. In most cases, effects were observable within 30 min of exposure and persisted or faded during a period of depuration in uncontaminated water of similar duration. In ovigerous females exposed to Cd and PAHs, effects appeared to be more pronounced during the depuration period, suggesting that carrying ovisacs may impair recovery. We quantified differences in the distribution of swimming speed values by considering the relative frequencies of periods of break, slow and fast swimming and we observed a trend toward faster movements in the presence of pollutants. The degree of trajectory complexity, estimated through their fractal dimension, was unaffected by pollutants. Since both narcotic and non-narcotic pollutants induced hyperactivity, our results suggest that changes in behavior after a short-term exposure may be independent of the general mode of action of the chemicals. The increase in speed and activity resembles an escape reaction permitting copepods to evade stressful conditions. Overall, these results indicate that environment-relevant concentrations of pollutants can induce rapid changes in copepod behavior. Since behavioral processes represent a fundamental element in the ecology of copepods, our results raise concern about the effects of background levels of pollution on a major component of the plankton community. The long-term response of copepods to waterborne pollutants, their synergistic effects and their interactions with other environmental factors need further investigation

International audience; In order to enhance encounters with prey, planktonic predators may display different swimming behavior with respect to food availability and distribution. In this study, we used 3D video techniques to record the swimming behavior of malabar grouper (Epinephelus malabaricus) larvae in both the absence and the presence of prey (Artemia sp. nauplii). Swimming properties were investigated in all of the 3D, the two vertical, and the horizontal projections using scale-dependent (mean speed and Net to Gross Displacement Ratio) and scale-independent (fractal dimension) metrics. When prey was added, larvae swam slower and in a less convoluted way as compared to what was observed in the absence of food. The results obtained with scale-dependant metrics were confirmed by those obtained with scale-independent analyses. Both unveiled the anisotropy of the swimming behavior of grouper larvae that tend to swim toward the vertical axis in order to maximize encounters with prey patches. This study shows that malabar grouper larvae can optimize their search volume by switching their behavior and further draws attention to the need to consider both vertical- and horizontal-projections components while addressing the plankter's swimming trajectories

The objective of this study was to determine the effect of once-yearly zoledronic acid on the number of days of back pain and the number of days of disability (ie, limited activity and bed rest) owing to back pain or fracture in postmenopausal women with osteoporosis. This was a multicenter, randomized, double-blind, placebo-controlled trial in 240 clinical centers in 27 countries. Participants included 7736 postmenopausal women with osteoporosis. Patients were randomized to receive either a single 15-minute intravenous infusion of zoledronic acid (5 mg) or placebo at baseline, 12 months, and 24 months. The main outcome measures were self-reported number of days with back pain and the number of days of limited activity and bed rest owing to back pain or a fracture, and this was assessed every 3 months over a 3-year period. Our results show that although the incidence of back pain was high in both randomized groups, women randomized to zoledronic acid experienced, on average, 18 fewer days of back pain compared with placebo over the course of the trial (p = .0092). The back pain among women randomized to zoledronic acid versus placebo resulted in 11 fewer days of limited activity (p = .0017). In Cox proportional-hazards models, women randomized to zoledronic acid were about 6% less likely to experience 7 or more days of back pain [relative risk (RR) = 0.94, 95% confidence interval (CI) 0.90–0.99] or limited activity owing to back pain (RR = 0.94, 95% CI 0.87–1.00). Women randomized to zoledronic acid were significantly less likely to experience 7 or more bed-rest days owing to a fracture (RR = 0.58, 95% CI 0.47–0.72) and 7 or more limited-activity days owing to a fracture (RR = 0.67, 95% CI 0.58–0.78). Reductions in back pain with zoledronic acid were independent of incident fracture. Our conclusion is that in women with postmenopausal osteoporosis, a once-yearly infusion with zoledronic acid over a 3-year period significantly reduced the number of days that patients reported back pain, limited activity owing to back pain, and limited activity and bed rest owing to a fracture.

International audience; Individual variation in morphology is linked to organism displacement in numerous taxa. This relationship among adult copepods has previously received little attention. In this study, we questioned whether the swimming behaviour of three morphologically different adult states of Pseudodiaptomus annandalei (i.e. males, non-ovigerous and ovigerous females) could be differentiated. Two-dimensional video observations revealed that some swimming patterns were common to all adult states, whereas others were more specific to one of the adult states. Males swim in a straight way, ovigerous females exhibit jerky swimming behaviour, and non-ovigerous females exhibit slow and steady gliding, interrupted occasionally by jumps. Direct measures of the swimming behaviour (i.e. mean, maximal and probability density of speed) for a large number of trajectories were considered first. Deeper comparisons of each sexual state were conducted using scale-dependant (i.e. net-to-gross displacement ratio), scale-independent (power spectrum, multi-fractal) metrics and symbolic analysis. The combined analysis emphasized the differences (e.g. male swimming patterns were slower and less complex, both ovigerous and non-ovigerous female swimming patterns were faster and more complex) and similarities (e.g. all swimming patterns were different from the Brownian motion) between adult swimming patterns. The multi-fractal approach identified differences between the two sexes suggesting differential swimming behaviour. In an ecological discussion, we relate these differences to mating and predator avoidance strategies

International audience; The Danshuei River embouchure is the largest estuarine ecosystem in northern Taiwan. The interacting effects of wastewater discharge from Taipei City and Taipei County into the river and seawater intrusion are the main determinants of the community composition, distribution, and abundance of zooplankton in this estuarine ecosystem. In the present study, we analyzed the abundance, distribution, and diversity of zooplankton, synoptically collected at 25 (19 marine and 6 estuarine) stations in this ecosystem. In total, 28 zooplankton groups were identified, including the top 3 most abundant groups: Calanoid copepods, larval stages, and Noctilucales. Among copepods, 46 species were identified from the estuarine stretch, whereas during the same period, 86 species of copepods were recorded in waters offshore of the estuary mouth, which is the boundary of the East China Sea and northeastern tip of the Taiwan Strait. Mesozooplankton abundances and distributions were highly variable among stations, indicating a highly fluctuating ecosystem. Zooplankton abundances were not correlated with chlorophyll a levels. Copepod diversity but not abundance showed a significant positive correlation with salinity (r = 0.764). The recorded salinity levels and zooplankton species compositions suggest that seawater intrusion up to station 3 of our study acts as a major driving force for zooplankton distribution and diversity in the Danshuei Estuary. Hierarchical classification revealed higher interannual variability in the occurrence of copepods species; at the 1st hierarchical level, samples collected in Oct. 2001 at stations 2, 3, and 4 were completely separated from other samples. Among these groups, the upstream station 4 was exclusively represented by the euryhaline estuarine calanoid copepod, Pseudodiaptomus annandalei, at a density of 1631 individuals (ind.)/m3, station 3 was represented by Pse. annandalei and Apocyclops borneoensis with respective densities of 552.5 and 1.8 ind./m3, and the seaward station 2 recorded Pse. annandalei, Paracalanus aculeatus, and A. borneoensis at respective densities of 364.9, 6.9, and 1.2 ind./m3. At the 2nd hierarchical level, samples collected in Apr. 2002 were segregated from the others and exclusively contained coastal marine and euryhaline species. The 3rd hierarchical level included species occurring with no significant variations and classified species into 3 groups: (i) species with relative abundances of 1.4%-2.9% occurring during the post-spring period but without significant temporal variations, (ii) the freshwater species of cyclopoid copepod, Mesocyclops pehpeiensis, and (iii) copepod species represented by local coastal, marine, and brackish-water species characteristic of warm tropical and subtropical waters. The Euclidean distance measurement separated the copepod community into 5 groups. The most indicative euryhaline species at upstream stations, Pse. annandalei was separated at the 1st level withoutclustering with any other species. The 2nd most abundant species, Mesocyclops pehpeiensis, grouped with other coastal species at the 2nd level of grouping; however it was separated at the 3rd level of grouping without associating with any other coastal or marine species.

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The Thirteenth East Asia-Pacific Conference on Structural Engineering and Construction (EASEC-13), September 11-13, 2013, Sapporo, Japan.