Abundance of copepods during POLARSTERN cruise ANT-XXI/2 (BENDIX)

The main emphasis of this study was to analyse the short-term development of abundance, population structure and vertical distribution of the dominant calanoid copepods during a phytoplankton bloom in the coastal area of the eastern Weddell Sea in December 2003. Microcalanus pygmaeus was by far the most abundant calanoid species. Metridia gerlachei, Ctenocalanus citer, Calanoides acutus, Calanus propinquus and the ice-associated Stephos longipes were also present in considerable proportions. The observed changes in the population characteristics and parameters of these species are described in detail and discussed in the context of the spring phytoplankton bloom. A conspicuous event occurring during the final stage of the study was the development of a strong storm. While the results suggest that this storm did not have any considerable influence on the populations of all other investigated copepod species, it very likely caused pronounced changes in the S. longipes population present in the water column. Before the storm, S. longipes was found primarily in the upper 100 m of the water column, and its population was dominated by adults (mean proportion = 41%) and the copepodite stage I (mean proportion = 30%). After the storm, the abundance increased considerably, and the copepodite stage I contributed by far the largest proportion (53%) of the total population indicating that the early copepodite stages probably had been released from the sea ice into the under ice water layer due to ice break-up and ice melt processes caused by the storm.

Eocene calcareous nannofossils of ODP Leg 149 sites

Five sites were drilled on the Iberia Abyssal Plain, west of the Iberian Peninsula. Four holes (897C, 897D, 899B, and 900A) yielded Eocene sediments that consist of turbidites and contourites. The Eocene section above the continental crust at Site 900 is continuous (from nannofossil Zones NP10 to NP20) and considerably expanded because of the site's relatively shallow depth, which remained consistently above the carbonate compensation depth (CCD). Sites 897 and 898, situated in deeper water above the ocean/continent transition, on the other hand, have noncontinuous, relatively short Eocene sections (from Zones NP14 to NP20 at Site 897 and from Zones NP19 to NP20 at Site 899). Nannofossils are abundant, diverse, and moderately to poorly preserved; they provide the primary means of dating the Eocene sediments recovered during Leg 149.

Lettres d'un diplomate danois en Espagne, 1798-1800.

"Extrait de la Revue hispanique, tome IX".

Tractatvs de crimine laesae maiestatis insignis, et elegans ...

Title vignette.

The origin and evolution of the surfactant system in fish: Insights into the evolution of lungs and swim bladders

Several times throughout their radiation fish have evolved either lungs or swim bladders as gas-holding structures. Lungs and swim bladders have different ontogenetic origins and can be used either for buoyancy or as an accessory respiratory organ. Therefore, the presence of air-filled bladders or lungs in different groups of fishes is an example of convergent evolution. We propose that air breathing could not occur without the presence of a surfactant system and suggest that this system may have originated in epithelial cells lining the pharynx. Here we present new data on the surfactant system in swim bladders of three teleost fish ( the air-breathing pirarucu Arapaima gigas and tarpon Megalops cyprinoides and the non-air-breathing New Zealand snapper Pagrus auratus). We determined the presence of surfactant using biochemical, biophysical, and morphological analyses and determined homology using immunohistochemical analysis of the surfactant proteins (SPs). We relate the presence and structure of the surfactant system to those previously described in the swim bladders of another teleost, the goldfish, and those of the air-breathing organs of the other members of the Osteichthyes, the more primitive air-breathing Actinopterygii and the Sarcopterygii. Snapper and tarpon swim bladders are lined with squamous and cuboidal epithelial cells, respectively, containing membrane-bound lamellar bodies. Phosphatidylcholine dominates the phospholipid (PL) profile of lavage material from all fish analyzed to date. The presence of the characteristic surfactant lipids in pirarucu and tarpon, lamellar bodies in tarpon and snapper, SP-B in tarpon and pirarucu lavage, and SPs ( A, B, and D) in swim bladder tissue of the tarpon provide strong evidence that the surfactant system of teleosts is homologous with that of other fish and of tetrapods. This study is the first demonstration of the presence of SP-D in the air-breathing organs of nonmammalian species and SP-B in actinopterygian fishes. The extremely high cholesterol/disaturated PL and cholesterol/PL ratios of surfactant extracted from tarpon and pirarucu bladders and the poor surface activity of tarpon surfactant are characteristics of the surfactant system in other fishes. Despite the paraphyletic phylogeny of the Osteichthyes, their surfactant is uniform in composition and may represent the vertebrate protosurfactant.

Production of triploid Kuruma shrimp, Marsupenaeus (Penaeus) japonicus (Bate) nauplii through inhibition of polar body I, or polar body I and II extrusion using 6-dimethylaminopurine

This study investigated the chromosome ploidy level of Marsupenaeus (Penaeus) japonicus (Bate) non-viable (unhatched) embryos and nauplii after exposure to 6-dimethylaminopurine (6-DMAP), timed to stop either polar body (PB) I, or PBI and II extrusion. Embryos from eight separate families or spawnings were exposed to 150 or 200 mu M 6-DMAP from 1- to 3-min post-spawning detection (psd) for a 4- to 5-min duration (timed to stop PBI extrusion). Separate aliquots of embryos from five of the same spawnings were also exposed to 200 mu M of 6-DMAP from 1- to 3-min psd for a 16-min duration (timed to stop both PBI and II extrusion). For one spawning, a third aliquot of embryos was exposed to 400 p M of 6-DMAP from 1- to 3-min psd for a 16-min duration (timed to stop both PBI and II extrusion). At 18-h psd, non-viable embryo and nauplii samples were taken separately for fluorescent activated cell sorting (FACS). FACS revealed that there were diploids and triploids among all treated non-viable embryos and nauplii. All control non-viable embryos and nauplii were diploid. Percentages of triploid induction for the 4- to 5-min and 16-min durations were not significantly different (P > 0.05). Additionally, no difference was found in the triploidy level of nonviable embryos compared to nauplii in these treatments. The percentage of triploid embryos and nauplii when exposed to 6-DMAP for a 4- to 5-min duration ranged from 29.57% to 99.23% (average 55.28 +/- 5.45%) and from 5.60% to 98.85% (average 46.70 +/- 7.20%), respectively. The percentage of triploid embryos and nauplii when exposed to 6-DMAP for a 16-min duration ranged from 11.71% to 98.96% (average 52.49 +/- 11.00%) and from 47.5% to 99.24% (average 79.38 +/- 5.24%), respectively. To our knowledge, this is the first documentation of successful PBI or PBI and II inhibition in shrimp. This study conclusively shows that treatment of M. japonicus embryos with 6-DMAP at 1- to 3-min pscl for either a 4- to 5-min duration (timed to stop PBl extrusion) or 16-min duration (timed to stop both PBI and II extrusion) results in viable triploid nauplii. (c) 2006 Elsevier B.V. All rights reserved.

The effectiveness of heat, cold and 6-dimethylaminopurine shocks for inducing tetraploidy in the Kuruma shrimp, Marsupenaeus japonicus (Bate)

In this study tetraploid Marsupenaeus japonicus (Bate) embryos were produced by preventing the first division in mitosis. The effectiveness of temperature and chemical shocks for producing tetraploid M. japonicus were assessed when applied at different times postspawning and for different durations. Tetraploid M. japonicus embryos (spawned at 27 degrees C) were produced by heat shocks at 35 degrees C and 36 degrees C in three and eight spawning samples respectively, and a cold shock at 5 degrees C in a single spawning sample. All temperature shocks inducing tetraploidy were applied 18-23 min postspawning for a 5-10 min duration. The percentage of spawnings successfully inducing tetraploid embryos (i.e., frequency of induction) ranged from 33.33% to 66.67% for the 21, 22 and 23 min postspawning heat shock treatment regimes. The percentage of tetraploid embryos within an induction (i.e., induction rate), as determined by flow cytometry, ranged from 8.82% to 98.12% (ave. S.E.) (34.4 +/- 21.4%) for the 35 degrees C shock treatments, from 13.12% to 61.02% (35.0 +/- 5.0%) for the 36 degrees C shock treatments and was 15% for the 5 degrees C cold shock treatment. No tetraploids were produced for spawnings that received heat shocks above 36 degrees C or below 35 degrees C, or for cold shocks above 5 degrees C for any of the tested postspawning treatment and duration times. Chemical shock with 150 mu M 6-dimethylaminopurine did not result in tetraploid M. japonicus embryos at any of the tested postspawning treatment times and durations. Tetraploid M. japonicus embryos were nonviable, with no tetraploid larvae being detected by flow cytometry. Based on our results heat shocking of M. japonicus embryos at 36 degrees C, 23 min postspawning for a 5-10 min duration is the most effective means to produce tetraploids through inhibition of the first mitotic division (taking into consideration the importance of frequency and induction rate equally).

The pearl oysters, Pinctada maxima and P margaritifera, respond in different ways to culture in dissimilar environments

Growth, Condition Index (CI) and survival of the pearl oysters, Pinctada maxima and R margaritifera, were measured in three size groups of oysters over 14 months at two dissimilar environments in the Great Barrier Reef lagoon. These were the Australian Institute of Marine Science (AIMS) in a mainland bay and Orpheus Island Research Station (OIRS) in coral reef waters. Temperature, suspended particulate matter (SPM) and particulate organic matter (POM) were monitored during the study. Temperature at AIMS fluctuated more widely than at OIRS both daily and seasonally, with annual ranges 20-31 degrees C and 22-30 degrees C, respectively. Mean SPM concentration at AIMS (11.1 mg l(-1)) was much higher than at OIRS (1.4 mg l(-1)) and fluctuated widely (2-60 mg l(-1)). Mean POM level was also substantially higher at AIMS, being 2.1 mg l(-1) compared with 0.56 mg l(-1) at OIRS. Von Bertalatiffy growth curve analyses showed that P. maxima grew more rapidly and to larger sizes than P. margaritifera at both sites. For the shell height (SH) of R maxima, growth index phi'=4.31 and 4.24, asymptotic size SHinfinity = 229 and 205 mm, and time to reach 120 mm SH (T-(120))= 1.9 and 2.1 years at AIMS and OIRS, respectively. While for P margaritifera, phi'=4.00 and 4.15, SHinfinity = 136 and 157 mm, and T-(120) = 2.5 and 3.9 years at AIMS and OIRS, respectively. R maxima had significantly lower growth rates and lower survival of small oysters during winter compared with summer. There were, however, no significant differences between the two sites in growth rates of P. maxima and final Cl values. In contrast, P. margaritifiera showed significant differences between sites and not seasons, with lower growth rates, survival of small oysters, final Cl values and asymptotic sizes at AIMS. The winter low temperatures, but not high SPM at AIMS, adversely affected P. maxima. Conversely, the high SPM levels at AIMS, but not temperature, adversely affected P. margaritifera. This was in accordance with earlier laboratory-based energetics studies of the effects of temperature and SPM on these two species. P maxima has potential to be commercially cultured in ca. > 25 degrees C waters with a wide range of SPM levels, including oligotrophic coral reef waters with appropriate particle sizes. It is possible to culture R margaritifera in turbid conditions, but its poor performance in these conditions makes commercial culture unlikely. (c) 2005 Elsevier B.V. All rights reserved.

Data compilation on the biological response to ocean acidification: environmental and experimental context of data sets and related literature

The exponential growth of studies on the biological response to ocean acidification over the last few decades has generated a large amount of data. To facilitate data comparison, a data compilation hosted at the data publisher PANGAEA was initiated in 2008 and is updated on a regular basis (doi:10.1594/PANGAEA.149999). By January 2015, a total of 581 data sets (over 4 000 000 data points) from 539 papers had been archived. Here we present the developments of this data compilation five years since its first description by Nisumaa et al. (2010). Most of study sites from which data archived are still in the Northern Hemisphere and the number of archived data from studies from the Southern Hemisphere and polar oceans are still relatively low. Data from 60 studies that investigated the response of a mix of organisms or natural communities were all added after 2010, indicating a welcomed shift from the study of individual organisms to communities and ecosystems. The initial imbalance of considerably more data archived on calcification and primary production than on other processes has improved. There is also a clear tendency towards more data archived from multifactorial studies after 2010. For easier and more effective access to ocean acidification data, the ocean acidification community is strongly encouraged to contribute to the data archiving effort, and help develop standard vocabularies describing the variables and define best practices for archiving ocean acidification data.

Distribution of diatom species as abundance estimates from vertical multinet hauls from 150 m water depth in the Indian Ocean

During the Indian Ocean Expedition of R/V METEOR phytoplankton samples were taken with a multiple closing net (Multinet) at 103 stations. In this material the diatoms were investigated. In all 247 taxa could be identified which belong to 242 species and 5 varieties of formae of 80 genera. Of these 1 variety, 15 pecies, and 3 genera are newly described. New combinations were made for 18 species, and a number of old combinations was reinstated.

Stable carbon and oxygen isotope record of foraminifera from DSDP Hole 30-289

Sediments accumulate on the sea floor far from land with rates of a few millimetres to a few centimetres per thousand years. Sediments have been accumulating under broadly similar conditions, subject to similar controls, for the past 10 8 years and more. In principle we should be able to study the distribution of climatic variance with frequencies over the range 10**-3 to 10**-7 cycles per year with comparative ease. In fact, nearly all our data are heavily weighted towards the youngest part of the geological record. We study frequencies higher than 10**-4 cycles per year in the special case of a Pleistocene interglacial (the present one), and frequencies in the range 10**-4 to 10**-5 cycles per year in the special case of an ice-age. Although these may be of more direct interest to mankind than earlier periods, it may well be that we will understand the causes of climatic variability better if we can examine their operation over a longer time scale and under different boundary conditions. Rather than review the available data, I have collected some new data to show the feasibility of gathering a data base for examining climatic variability without this usual bias toward the recent. The most widely applicable tool for extracting climatic information from deep-sea sediments is oxygen isotope analysis of calcium carbonate microfossils. It is generally possible to select from the sediment both specimens of benthonic Foraminifera (that is, those that lived in ocean deep water at the sediment-water interface) and specimens of planktonic Foraminifera (that is, those that lived and formed their shells near the ocean surface, and fell to the sediment after death). Thus one is able to monitor conditions at the surface and at depth at simultaneous moments in the geological past. The necessity to analyse calcareous microfossils restricts investigation to calcareous sediments, but even with this restriction in sediment type there are many factors governing the rate of sediment accumulation. On a global scale, sediment accumulates so as to balance the input to the oceans from continental erosion. Even when averaged globally, long-term accumulation rates have varied by almost a factor of ten (Davies et al., 1977, doi:10.1126/science.197.4298.53). At the regional scale, surface productivity and deep-water physical and chemical conditions also affect the sediment accumulation rate. Since all these are susceptible to variation and may well vary in response to climatic change as well as other factors, it is extremely hazardous to attempt to express any climatic variable as a function of time on the basis of measurements originally made as a function of depth in sediment. Although time has been used as a basis for plotting Figs. i-8, these should be regarded as freehand sketches of climatic history rather than as time-series plots.

Benthic assemblages associated with native and non-native oysters are similar

Invasive species can impact native species and alter assemblage structure, which affects associated ecosystem functioning. The pervasive Pacific oyster, Crassostrea gigas, has been shown to affect the diversity and composition of many host ecosystems. We tested for effects of the presence of the invasive C. gigas on native assemblages by comparing them directly to assemblages associated with the declining native European oyster, Ostrea edulis. The presence of both oyster species was manipulated in intertidal and subtidal habitats and reefs were constructed at horizontal and vertical orientation to the substratum. After 12 months, species diversity and benthic assemblage structure between assemblages with C. gigas and O. edulis were similar, but differed between habitats and orientation, suggesting that both oyster species were functionally similar in terms of biodiversity facilitation. These findings support evidence, that non-native species could play an important role in maintaining biodiversity in systems with declining populations of native species.

Microbial community of black band disease on infection, healthy and dead part of scleractinian Montipora sp. colony at Seribu islands, Indonesia

It is crucial to understand the microbial community associated with the host when attempting to discern the pathogen responsible for disease outbreaks in scleractinian corals. This study determines changes in the bacterial community associated with Montipora sp. in response to black band disease in Indonesian waters. Healthy, diseased, and dead Montipora sp. (n = 3 for each sample type per location) were collected from three different locations (Pari Island, Pramuka Island, and Peteloran Island). DGGE (Denaturing Gradient Gel Electrophoresis) was carried out to identify the bacterial community associated with each sample type and histological analysis was conducted to identify pathogens associated with specific tissues. Various Desulfovibrio species were found as novelty to be associated with infection samples, including Desulfovibrio desulfuricans, Desulfovibrio magneticus, and Desulfovibrio gigas, Bacillus benzoevorans, Bacillus farraginis in genus which previously associated with pathogenicity in corals. Various bacterial species associated with uninfected corals were lost in diseased and dead samples. Unlike healthy samples, coral tissues such as the epidermis, endodermis, zooxanthellae were not present on dead samples under histological observation. Liberated zooxanthellae and cyanobacteria were found in black band diseased Montipora sp. samples.

Genetic effect of domestication selective pressures on Pacific oyster at larval stage

Among bivalve species, the Pacific oyster, Crassostrea gigas, is the most economically important bivalve production over the world. Today, C. gigas is subject to an important production effort that leads to an intensive artificial selection. Larval stage is relatively unknown, specifically in a domestication context. Genetic consequence of artificial selection is still at a preliminary study. We aimed to tackle the consequence of inconscient domestication on the variance reproductive success focusing on larval stage, keystone of the life cycle. We studied two kinds of specific selective processes that common hatchery rearing practices exert : the effect of discarding the smallest larvae on genetic diversity and the artificial environment rearing effect via the temperature providing a contrast resembling wild versus hatchery conditions (20 and 26°C). In order to monitor the effect of the selection of fast growing larvae by sieving, growth variability and genetic diversity in a larval population descended from a factorial breeding was studied. We used a mixed-family approach to reduce potentially confounding environmental biais. The retrospective assignment of individuals to family groups has been performed using a three microsatellite markers set. Two different rearing were carried out in parallel. For three (replicates) 50-l tanks, the smallest larvae were progressively discarded by selective sieving, whereas for the three others no selective sieving was performed. The intensity of selective sieving was adjusted so as to discard 50% of the larvae over the whole rearing period in a progressive manner. As soon as the larvae reached the pediveliger stage, ready to settle larvae were sampled for genetic analysis. Regarding the artificial environment rearing effect via the temperature, we used a similar mixed-family approach. The progeny from a factorial breeding design was divided as follows: three (replicates) 50-l tanks were dedicaced to a rearing at 26°C versus 20°C for three others 50-l tanks. The whole size variability was preserved for this experiment. Individual growth measurements for larvae genetically identified have been performed at days 22 and 30 after fertilization for both conditions. In a same way, we collected individual measurements for genotyped juvenile oysters (80 days after fertilization). At a phenotypic scale, relative survival and settlement success for larvae with sieving were higher. Sieving appears as a time-saving process associated with a better relative survival ratio. But in the same time, our results confirm that a significant genetic variability exist for early developmental traits in the Pacific oyster. This is congruent with the results already obtained that investigated genetic variability and genetic correlations in early life-history traits of Crassostrea gigas. Discarding around 50% of the smallest larvae can lead to significant selection at the larval stage.

Apport d'un programme de génétique à une filière de production aquacole : l'exemple de l'ostréiculture

Two oyster species are currently present along the French coasts : the indigenous European flat oyster (Ostrea edulis), and the Pacific cupped oyster (Crassostrea gigas), that has been introduced from Japan since the beginning of the 70ies. The flat oyster successively suffered from two protozoan diseases during the 60ies and its production decreased from 20 000 tons/year by that time to 1 500 tons/year nowadays. Consequently, the oyster production is principally (99%) based upon the Pacific oyster species with approximately 150 000 tons/year among which 90% are grown from the natural spat. However, the hatchery production of this species is developing and was estimated to 400 to 800 millions spat in 2002. Moreover, strengthened relationships between IFREMER and the 5 commercial hatcheries, that all joined the SYSAAF (Union of the French poultry, shellfish and fish farming selectors), allow to plan for new genetic breeding programs. At the end of the 80ies, IFREMER initiated a genetic breeding program for the resistance of the European flat oyster to the bonamiosis, and obtained strains more tolerant to this disease. After two generations of massal selection, molecular markers had identified a reduced genetic basis in this program. It was then reoriented to an intra-familial selection. However, we were confronted to a zootechnic problem to manage such a scheme and we compromised by an intra-cohorts of families selection scheme managed using molecular markers. The program has now reached the transfer level with experimentation at a professional scale. Concerning the Pacific cupped oyster, and in parallel with the obtaining and the study of polyploids, performance of different Asian cupped oyster strains were compared to the one introduced in France thirty years ago and currently suffering from summer mortalities. The local strain exhibited better performance, certainly based upon a good local adaptation. In other respects, although early growth is a relevant criteria for selection for growth to commercial stage, it is not to be privileged in the context of an oyster producing region with a limited food availability. Contrary, the spat summer mortality became a priority for numerous teams (genetic, physiology, pathology, ecology,...) joined in the MOREST program. The first results showed important survival differences between fullsib and halsib families. They indicate a genetic determinism to this character "survival" and promote for its selection.