ALBERT

Description: Four research surveys of Falkland Island waters were carried out to determine the distribution and abundance of the early life-history stages of Loligo gahi (d'Orbigny, 1835) in the austral winter of 1988 and the austral springs of 1990, 1991 and 1992. Juveniles were caught during three of the four surveys in both Bongo nets and an RMT8 net. In each case, greatest numbers were consistently caught in waters of ≤100 m to the south and east of East Falkland. The use of an opening/closing net in 1992 showed that most L. gahi juveniles aggregate close to the sea floor and are more available to the sampling gear by night than by day. Limited temperature data for the 1991 and 1992 surveys suggest that distribution on the coastal shelf may be associated with water-column structure. In 1992 when temperature data implied a mixed water column, juveniles were caught in deeper water than in 1991 when the water column was stratified. The results suggest that the spawning grounds of L. gahi are probably situated to the south and east of the Falkland Islands, at least for squid hatched in the austral winter/spring.

Description: A total of 40 (29 female and 11 male) Ross seals were sampled in January over three years. Seals were weighed, measured and age determined by counting dentine lines in teeth. Stomach contents were identified against reference material and species of helminths were determined using standard techniques. Asymptotes in body mass and length are reached at some nine years of age. Age class varied from 2–20 years. Antarctic silverfish Pleurogrammma antarcticum was the only fish species identified. Psychroteuthis glacialis dominated the squid component. Fish was dominant in three samples, squid was the exclusive component in two samples and a minor component in another two. Glandicephalus antarcticus, Diphyllobothrium wilsoni and Contracaecum spp were the dominant helminths present. The high proportion of empty or nearly empty stomachs conforms with the knowledge that this species moults and consequently fasts in January.

Description: Geographic variation in the squid Loligo forbesi was investigated using multivariate analysis of morphometric and meristic characters in samples of squid taken from 13 localities in the Northeast Atlantic Ocean. Two character sets, body morphometrics and beak morphometrics, indicated similar patterns of variation, with squid from the Azores differing markedly from those on the continental shelf. No consistent pattern was apparent in meristic data. Partial Mantel tests indicated that similarity matrices for morphological data were significantly correlated with distance matrices for (a) geographic proximity, (b) whether the capture site was on the continental shelf or the Azorean bank, and (c) (beak data only) average seasurface temperature at site of capture. Partial Mantel tests on allozyme data for the same individuals support hypothesis (b). The results suggest that L. forbesi in the Azores may reasonably be regarded as a distinct stock, differing significantly from L. forbesi on the continental shelf.

Description: Abralia trigonura is a small squid that is an important member of the mesopelagic boundary community around Hawaii. Squids were aged by examining statolith growth increments, and various reproductive parameters were measured. Female longevity is ∼6 mo, and they become sexually mature at ∼3.5 mo. Male longevity is the same, but they become sexually mature at ∼2.5 mo. This species appears to be a multiple spawner, and peculiarities in the number of eggs found in the oviducts suggests that they spawn every few days. Possible advantages of this reproductive mode are examined.

Description: The home range system of the coelacanth Latimeria chalumnae was investigated along 11 km coastline at Grande Comore, Western Indian Ocean, between 1987 and 1991. 67 individuals were identified on individual white dot patterns. The home range consisted of daytime caves where fish aggregated in groups of up to 14 individuals while at night individuals moved singly downwards to a depth of 250 to 300 m in search of food. Site fidelity of at least 5 yr was found. The coelacanths used several caves within their home ranges. Cave size, cave occupation rate, average and maximum group size and cave preferences were studied. Tracking experiments with ultrasonic transmitters revealed horizontal home ranges of at least 8 km width. Population estimates of 200 to 230 individuals at Grande Comore confirm earlier counts. Large home ranges and highly mobility in a topographically narrow habitat apparently favoured inbreeding of the small local island population.

Description: Eleven fish species from the Weddell Sea (Antarctic) were examined for infestation with anisakid nematodes. Two species of the genus Contracaecum and the sealworm Pseudoterranova decipiens were isolated from the liver and the body cavity of fish affected. Only two specimens of P. decipiens (1.4%) partly invaded the belly flaps. The following fish species were infested by P. decipiens at the given prevalences: Cygnodraco mawsoni (74.4%), Trematomus scotti (23.2%), Pagetopsis maculatus (10.0%), Cryodraco antarcticus (7.1%), Trematomus lepidorhinus (3.0%), and Dolloidraco longedorsalis (2.7%). All of these, except Trematomus scotti, are new host records. Chaenodraco wilsoni, Chionodraco myersi, Gerlachea australis, Racovitzia glacialis and T. eulepidotus were not infested. The reasons for low prevalence and intensity of infestation are seen in the difficulties of P. decipiens in completing its benthic life cycle in the Weddell Sea environment, in the absence of shallow coastal waters due to the floating shelf-ice. Cygnodraco mawsoni is a crucial intermediate host, without which completion of the parasite life cycle might not be possible. In order to clarify the taxonomical position of Antarctic Pseudoterranova, morphological comparisons with specimens of P. decipiens from the German and Norwegian coast were made using scanning electron microscopy. Results revealed no differences; hence, all specimens studied belong to the same species P. decipiens.

Description: Coupling of physical, biological and chemical processes associated with particle resuspension and seston flux was investigated at three sites in the North Sea with contrasting water column (mixed/stratified) and seabed (cohesive/non-cohesive) characteristics.

Description: RNA/DNA ratios in individual herring (Clupea harengus) larvae (collected from Kiel Bay, Baltic Sea, in 1989) were measured and proved suitable for determining nutritional status. Significant differences between fed and starving larvae appeared after 3 to 4 d of food deprivation in larvae older than 10 d after hatching. The RNA/DNA ratio showed an increase with age or length of the larvae and was less pronounced in starving larvae compared to fed larvae. The individual variability of RNA/DNA ratios in relation to larval length of fed larvae and of larvae deprived of food for intervals of 6 to 9 d is presented. Based on the length dependency and the individual variability found within the RNA/DNA ratios, a laboratory calibration is given to determine whether a larva caught in the field has been starving or not. An example for a field application is shown.

Description: A hierarchy of ENSO (El Niño/Southern Oscillation) prediction schemes has been developed which includes statistical schemes and physical models. The statistical models are, in general, based on advanced statistical techniques and can be classified into models which use either low-frequency variations in the atmosphere (sea level pressure or surface wind) or upper ocean heat content as predictors. The physical models consist of coupled ocean-atmosphere models of varying degrees of complexity, ranging from simplified coupled models of the lsquoshallow waterrsquo-type to coupled general circulation models. All models, statistical and physical, perform considerably better than the persistence forecast on predicting typical indices of ENSO on lead times of 6 to 12 months. The most successful prediction schemes, the fully physical coupled ocean-atmosphere models, show significant prediction abilities at lead times exceeding one year period. We therefore conclude that ENSO is predictable at least one year in advance. However, all of this applies to gross indices of ENSO such as the Southern Oscillation Index. Despite the demonstrated predictability, little is known about the predictability of specific features known to be associated with ENSO (e.g. Indian Monsoon rainfall, Southern African drought, or even off-equatorial sea surface temperature). Nor has the relative importance for prediction of different regional anomalies or different physical processes yet been established. A seasonal dependence in predictability is well established, but the processes responsible for it are not fully understood.

Description: The Cenozoic margins of the Norwegian-Greenland Sea offer ideal conditions for passive margin studies. A series of structural elements, first observed on these margins, led to the concept of volcanic passive margins. Questions still remain about the development of such features and the location of the boundary between oceanic and continental crust. Despite the thin sediment cover of the margins, seismic reflection data are not able to image the deeper structures due to the occurrence of igneous rocks at shallow depth. This paper presents a 320-km long profile perpendicular to the strike of the main structural units of the Lofoten Margin in Northern Norway. A geological model is proposed, based on observations made with ocean bottom seismographs, which recorded seismic refraction data and wide angle reflections, along with a seismic reflection profile covering the same area. Ray-tracing was used to calculate a geophysical model from the shelf area into the Lofoten basin. The structures typical of a volcanic passive margin were found, showing that the Lofoten Margin was influenced by increased volcanic activity during its evolution. The ocean/continent transition is located in a 30-km wide zone landwards of the Vøring Plateau escarpment. The whole margin is underlain by a possibly underplated, high velocity layer. Evidence for a pre-rift sediment basin landwards of the escarpment, overlain by basalt flows, was seen. These structural features, related to extensive volcanism on the Lofoten Margin, are not as distinct as further south along the Norwegian Margin. Viewed in the light of the hot-spot theory of White and McKenzie (1989) the Lofoten Margin can be interpreted as a transitional type between volcanic and non-volcanic passive margin.

Description: Based on a combined data set of sea surface temperature, zonal surface wind stress and upper ocean heat content the dynamics of the El Niño phenomenon is investigated. In a reduced phase space spanned by the first four EOFs two different stochastic models are estimated from the data. A nonlinear model represented by a simulated neural network is compared with a linear model obtained with the principal oscillation pattern (POP) analysis. While the linear model is limited to damped oscillations onto a fix point attractor, the nonlinear model recovers a limit cycle attractor. This indicates that the real system is located above the bifurcation point in parameter space supporting self-sustained oscillations. The results are discussed with respect to consistency with current theory.

Description: Energy requirements of resting Adélie (Pygoscelis adeliae), Gentoo (P. papua) and Chinstrap (P. antarcticd) penguin chicks were determined with respect to body mass via respirometry in Antarctica. Resting metabolic rates of all Pygoscelid penguin chicks were similar (ANOVA p=0.91) and best described by E=0.0096 M0.98 (n=24, r2=0.97), where E is power (W) and M is mass (g). Using the results obtained here and data published in the literature, I determined a) the amount of food needed from hatching to fledging as 29.8, 31.7 and 56.4 kg per chick for Adélie, Chinstrap and Gentoo penguins, respectively and b) the average amount of food left daily to the parent after feeding the brood throughout the breeding period. Parents keep only a minimum of food for themselves just prior to the time when chicks begin forming crèches. Thereafter, nest relief intervals are increased, and the amount of food parents can keep for themselves rises. The results of both models are discussed with respect to available data on Pygoscelid penguin food requirements.

Description: Multiple opening-closing nets of 0.05 mm mesh size were employed to study the community structure and vertical distribution of microcopepods at selected stations in the Red Sea, Arabian Sea and Eastern Mediterranean Sea down to a maximum depth of 1850 m. Calanoids, cyclopoids (Oithona and Paroithona) and poecilostomatoids (mainly Oncaea) were the 3 most abundant orders. In the epipelagic zone (0–100 m), these orders occurred at similar abundance levels, whereas in the meso- and bathypelagic zones the poecilostomatoid genus Oncaea dominated numerically by about 60–80% of all copepodids. The species diversity of Oncaea in the Red Sea is compared with preliminary results from the two adjacent regions. In the deep Eastern Mediterranean Sea, the number of species appears to be similar to that in the deep Red Sea and low as compared to the deep Arabian Sea. In this latter area an extremely speciose Oncaea fauna was found at depth below the oxygen-minimum-zone (900–1850 m). The results are related to the differences in the hydrographic conditions of these 3 areas.

Description: Many researchers use external recording or transmitting devices to elucidate the marine ecology of fish, mammals and birds. Deleterious effects of these instruments on the parameters researchers wish to measure are hardly ever discussed in the literature. Research has shown that, in penguins, volume and cross-sectional area of instruments negatively correlate with swimming speed. dive depth and breeding success, and that device colour affects bird behaviour. Here, a large (200 g, cross-sectional area 2100 mm2) streamlined device was attached to the lower back of Adélie penguins (Pygoscelis adeliae on Ardley Island, South Shetland Island in 1992) and its effects on bird swimming speed and energetics were measured in a water canal in Antarctica. Although the device was 10.5% of penguin cross-sectional area, swimming speed was reduced by only 8.3% and mean power input increased by only 5.6% while swimming. Although our streamlined device was five times more voluminous than one of our older units, the effect on swimming energetics could be reduced by 87%.

Description: We reconstructed past variations in CO2 partial pressure (local PCO2) in the surface waters of the East Atlantic equatorial upwelling zone over the last 330,000 years, based on the δ13C record of the (marine) organic matter in ‘Meteor’ core 16772. To deduce the initial δ13Corganic values of plankton and the CO2 solubility in surface water, the δ13C record was adjusted for i) past variations in (winter) sea surface temperature, ii) variations in the δ13C composition of inorganic carbon dissolved in the surface waters, using the δ13C values of G. ruber (white), and iii) isotopic fractionation during the degradation of settling organic matter in the water column and on the sediment surface. The calculated paleo-PCO2 variations in the surface waters show a strong signal at the obliquity frequency and are approximately parallel to the VOSTOK ice-core record of atmospheric PCO2 over the last 140,000 years. Holocene PCO2 values varied within the range of modern local PCO2, which is 350–400 ppmv compared to a pre-industrial atmospheric pCO2 level of 280 ppmv. This positive anomaly demonstrates the persistent CO2 release from upwelled subsurface water. The glacial-to-interglacial amplitudes of local PCO2 (at the core site) exceeded those of atmospheric pCO2 by 20–60%, with values of less than 250 to 300 ppmv during cold isotopic stages, which indicate a decreased net carbon outgassing from the ocean to the atmosphere. The close correlation between high paleo-PCO2 and low paleo-nutrient contents and paleoproductivity (r=0.7–0.8) suggests that the local PCO2 variations resulted mainly from CO2 transfer by phytoplankton production, especially over the last 170,000 years.

Description: Vesteris Seamount is a solitary submarine volcano located at 73-degrees-30' N, 9-degrees-10' W in the Greenland Basin. Steeply rising from a base depth of 3100 m to a minimum depth of approximately 130 m and striking 030-degrees/210-degrees, the feature lies approximately 300 km east of the east Greenland margin on an otherwise nearly flat and featureless seafloor. The main body of the seamount appears to have been formed episodically, the last of which culminated about 110 000 years ago. Subsequent, lower intensity volcanic activity continued sporadically until about 25 000 years ago, as evidenced by ash layers found in cores near the base of the feature. The smoothed surfaces at the summit make it likely that the seamount actually broached the surface during the Weichselian glacial period, between 8000 and 13 000 years ago. Two multibeam bathymetric investigations aboard PFS Polarstern during ARKTIS II/4 (1984) and ARKTIS VII/1 (1990), combined with geologic sampling. single-channel seismic profiling and underwater television coverage, have resulted in a new interpretation of both the morphology and origins of the seamount. Data collected aboard Polarstern from ARKTIS II/4 (1984) have been previously reported by Hempel et al. (1991), however, when combined with the ARKTIS VII/1 (1990) data set, a more detailed interpretation of the morphology and structure was feasible. This included the elongated shape of the feature and showed the existence of several small volcanic cones on the seamount flanks.

Description: Standing stock and size composition of the zooplankton comunity (〉100 μm) were studied in four depth strata of the upper 200 m of the water column during a “Meteor” cruise to the central Red Sea and Gulf of Aden in spring 1987. The central Red Sea was divided into a northern area of higher salinity and a less saline southern part. Both areas exhibited significant differences in zooplankton abundance and standing stock. The latter increased by the ratio 1:2:3 from the northern central Red Sea to its southern part and further south to the Gulf of Aden. For size structure analysis samples were fractionated into three size classes (100 to 300, 300 to 500, 500 to 5000 μm). In the central Red Sea the smallest size was dominant whereas in the Gulf of Aden the largest size fraction played a greater relative role than in the central Red Sea. This shift in size structure of the zooplankton community from the Red Sea to the Gulf of Aden is apparently primarily related to ecosystem difference between both areas, leading to a change in species composition. In addition, size reduction of individual species common to both seas may be of some significance in the extreme environment of the Red Sea.

Description: The application of microwave radiometry for rainfall estimation is discussed. The first part presents a description of processes by which hydrometeors affect microwave radiation. In order to show the state-of-art of rainfall estimation with space-borne microwave radiometry five algorithms are intercompared in the second part. Two are based on scattering, one on emission and two are mixed algorithms, which include both emission and scattering. The algorithms are applied to SSM/I observations over the Atlantic Ocean. The retrieved rainfall rates by the different algorithms partly differ a great deal. The differences depend on climatic regions, demonstrating that the algorithms are probably tuned to certain atmospheric conditions. The question arises whether a globally applicable algorithm is possible at all. A severe problem is the validation of the retrieved precipitation because hardly any direct observations are available. Thus an intercomparison of algorithms is today the only way to understand the behaviour of a scheme in different weather and climate situations and assess its results.

Description: In March/April 1991 hydrographic parameters (salinity, temperature) and hydrochemical parameters (concentrations of phosphate, nitrate, nitrite, ammonia, silicate and pH) were measured continuously in the surface water of the Baltic Sea and the North Sea. The hydrographic parameters were determined by means of a TS,pH probe and the chemical parameters were determined by means of an Auto Analyser. The cruise track through the Baltic Proper, the western Baltic Sea, the transition area to the North Sea and the North Sea with the mouth of the river Elbe was around 2050 nautical miles long and included some 2100 data-points. The different phases of the Baltic Sea's spring diatom bloom were inferred from the different nutrient concentrations measured; a comparison with the hydrographic data revealed that the bloom was largely unconnected to the hydrography. The same situation was encountered in the North Sea except that the spring bloom there had already reached a later phase. In those regions of the Baltic Sea where a plankton bloom had already occurred or was still under way, strong patchiness of the hydrochemical parameters was also observed; it was sometimes possible to relate it to the topography. This patchiness was far less pronounced in the North Sea and in regions of the Baltic Sea where conditions were still wintry. This paper discusses the advantages and possible applications of the method of continuous measurement of hydrochemical parameters across large areas with high temporal and spatial resolution.

Description: A method is presented to infer cloud liquid water path (LWP in kg/m2) over the ocean from passive microwave measurements of SSM/I. The algorithm to retrieve LWP is based on simulated satellite observations. They are calculated with a radiative transfer model applied to about 3000 radiosonde ascents over the Atlantic Ocean. Since radiosonde observations do not contain direct information about cloud water and ice, these parameters are parameterized based on relative humidity and temperature using modified adiabatic liquid water density profiles. A multiple linear regression is applied to the simulated radiances and the calculated LWP to derive the algorithm. The retrieval accuracy based on the regression analysis including instrumental noise is 0.03 kg/m2. Validation of the LWP-algorithm was pursued through a comparison with measurements of a ground-based 33 GHzmicrowave radiometer on board of R.V. “Poseidon” during the International Cirrus Experiment 1989 at the North Sea (ICE'89). The LWP values agree within the range of uncertainty caused by the different sampling characteristics of the observing systems. The retrieval accuracy for clear-sky cases determined using colocated METEOSAT data over the North Sea is 0.037 kg/m2 and confirms the accuracy estimated from regression analysis for the low liquid water cases. The algorithm was used to derive maps of monthly mean LWP over the Atlantic Ocean. As an example the Octobers of the 5 years 1987–1991 were selected to demonstrate the interannual variability of LWP. The results were compared with the cloud water content produced by the climate model ECHAM-T2 from the Max-Planck-Institut Hamburg. Observations during ICE'89 were used to check the accuracy of the applied radiative transfer model. Brightness temperatures were calculated from radiosonde ascents launched during the overpass of DMSP-F8 in cloud-free situations. The channel-dependent differences range from about −2 to 3 K. The possibility to identify different cloud types using microwave and infrared observations was examined. The main conclusion is that simultaneous microwave and infrared measurements enable the separation of dense cirrus and cirrus with underlying water clouds. A classification of clouds with respect to their top heights and LWP was carried out using a combination of SSM/I derived LWP and simultaneously recorded Meteosat IR-data during ICE'89.

Description: Some species of wide-spread tropical squids and pelgic octopuses (Histioteuthis hoylei, Alloposus mollis and others), based on beak findings in sperm whale stomachs, were common in the 1950s and early 1960s and widely distributed along the Kuril' Islands, eastern Kamchatka, in the Bering Sea, near the Aleutian Islands and the Gulf of Alaska, but later they were never recorded north of northwastern Honshu or southeast of the southern Kuril's. In 1990-1992 the squid Watasenia scintillans extended north to the middle Kuril's and, in smaller quantities, to the northern Kuril's while H. hoylei extended to the western Bering Sea. In the summer of 1992, Ancistrocheirus lesueurii, Mastigoteuthis dentata?, Eledonella pygmaea, and Allopsus mollis were also caught off the Shikotan, Kunashir, and Iturup Islands. A. lesueurii and E. pygmaea were caught in the Russian EEZ for the first time. We discuss why the warm-water species appear in the Russian Far Eastern seas again, after a long period of absence.

Description: Horizontal starch gel electrophoresis was used to investigate levels of genetic differentiation between four samples of the nominate squid species Martialia hyadesi Rochbrune and Mabille, 1889, obtained from regions of the Patagonian Shelf and Antarctic Polar Fron-tal Zone over 1000 km apart. M. hyadesi is an ecologically important South Atlantic ommastrephid squid and it is probable that, in the future, fishing effort will be increasingly directed towards this species. Details regarding the population structure of the species are therefore required. In comparison with the other three samples of M. hyadesi, one of the samples from the Patagonian Shelf (PAT 89II) exhibited fixed allelic differences at 16 of the 39 enzyme loci which were resolved (genetic identity, I=0.51). This high level of genetic differentiation contradicts the apparent morphological similarity between samples, indicating the presence of a cryptic or sibling congeneric species. Deviations from Hardy-Weinberg equilibrium and significant differences in allele distribution were also detected within and between the other three putative M. hyadesi samples, suggesting that the species fails to maintain effective panmixia across its geographical range. The occurrence of both temporal (1986 cf. 1989) and geographic structuring within the species complex is consequently indicated, caused possibly by an overlap of reproductively isolated stocks (stock mixing) outside their respective breeding areas. Low levels of genetic variability were detected throughout the samples examined, estimates of average heterozygosity per locus within the two species detected being in the order of 0.01 and 0.002. These values are discussed in relation to levels of genetic variability reported for other squid species, and in comparison with values typically expected for marine invertebrates.

Description: Lower and upper survival temperatures of microthalli of 25 species of South American Phaeophyceae isolated from central Peru (14°S) to the Canal Beagle (55°S) were determined using 2-wk exposure for the upper and 4-wk exposure for the lower limit. All species survive 4 wks at -2°C. With respect to the upper limit, species reported only from southernmost South America tolerate 19.9 to 24.5°C (n=8), and species occurring from Cape Horn to central Chile 24.6 to 27.4°C (n=7). Three species that occurred as far north as northern Chile and Peru before the 1982–1983 El Niño event, and whose northern limit was dramatically shifted southwards in 1983, tolerate 20.8 to 25.3°C, whereas five species that have survived in Peru tolerate 25.6 to 28.5°C. Tinocladia falklandica which tolerates 27.8 to 28.1°C but lives only in southernmost South America and Striaria attenuata, which tolerates 31.6 to 31.9°C but occurs at ca. 42°S, are exceptional. Their high temperature tolerance may have no adaptive value in South America. They are restricted to the cold-temperate region due to low temperature requirements for reproduction or for reasons yet unknown. In general, the northern distributional limits of the Phaeophyceae studied along the temperate Pacific coast of South America are reproduction boundaries, except in El Niño years when they are redefined according to the species' upper suvival limits. Temperature tolerance of isolates from northern Chile and Peru agrees well with maximum temperatures reached during the 1983 El Niño.

Description: During a cruise in the Baltic Sea in March/April 1991, dissolved lipids were concentrated from acidified sea water by adsorption on reversed phase material; the free fatty acids in the lipids were isolated. Titration of the acids with 0.01 mol/l methanolic KOH resulted in a very poor titration curve; assessing total concentration of organic acids in sea water by base titration appears to be impractical. After derivatization with p-phenylphenacyl bromide under crown ether catalysis the fatty acids were analyzed by micro-bore HPLC with UV-detection and comparison with standard reference substances. Some unknown fatty acids were characterized by GC/MS. Total concentrations were in the range from 1 to 4.5 nmol/l. They were the same in parallel samples liquid/liquid extracted with dichloromethane. The HPLC spectra of the fatty acids in both kinds of samples were also quite similar. This confirms earlier observations that adsorptive concentration of dissolved fatty acids and non-polar lipids from sea water is as effective as liquid/liquid extraction. Higher amounts of fatty acids can be concentrated by adsorption from large water volumes, thus lowering detection limits. Palmitic acid had by far the highest concentration in every sample followed by myristic acid, lauric acid, and stearic acid. Palmitoleic acid and oleic acid were the most abundant unsaturated acids. The other saturated and unsaturated acids had medium to low concentrations.

Description: Crossing studies revealed an intraspecifìc sterility barrier on the level of zygote formation between Japanese Sphaerotrichia divaricata and isolates of the same species from the Northeast Pacific and the North Atlantic. Because no consistent morphological differences exist between sporophytes from Japan and other areas, we propose not to distinguish the intersterile populations as different species. Japanese Sphaerotrichia and isolates from a recently detected population in the Étang de Thau, French Mediterranean coast, are interfertile. The crossing studies support the assumption that this Mediterranean population is a recent introduction from Japan.

Description: Regurgitations were collected from 41 black-browed albatross adults feeding chicks at Bird Island (54°S 38°W), South Georgia in February 1986. The samples were sorted into recognisable food categories and weighed. Cephalopods were identified by means of the lower beak, or in some cases the gladius, and allometric equations were used to calculate mantle length and wet body weight represented by beaks. The samples contained 35.5%Euphausia superba, 30.9% cephalopods and 27.1% fish, by weight. A total of 21 samples contained recognisable cephalopod remains and 20 contained specimens that could be identified. In all, 50 cephalopod specimens, representing an estimated 6,866 g wet weight, were identified. The diet was dominated in terms of numbers, weight and percent occurrence by the ommastrephid squidMartialia hyadesi, and in most cases the entire squid was present with only partial digestion of the skin and arm armature. The cranchiid squidGaliteuthis glacialis was the only other cephalopod of numerical importance but no soft parts were present suggesting that, although significant in the diet of the adults, this species was not being fed to chicks. One specimen each ofGonatus antarcticus, Chiroteuthis sp.,Histioteuthis sp. B. and the octopodidPareledone polymorpha were also present. The cephalopod composition of the diet corresponded closely with a collection made 10 years earlier. The commonest species in the bird's diet,M. hyadesi, has not been found in net and jig samples at South Georgia although it has been taken from the Antarctic Polar Frontal Zone to the west of the Island. The presence of almost complete, undigested, specimens ofM. hyadesi in the bird's diet indicates that it occurs relatively close to South Georgia.M. hyadesi preys largely on myctophid fishes, which themselves prey on small zooplankters, so a significant component of the black-browed albatross diet depends on a food chain which largely by-passesE. superba.

Description: The accumulation of parasites in a fish host is modelled as a function of the total amount of prey consumed. The accumulated parasite load is then expressed as a function of fish length so that the asymptotic growth, L∞, of any population of commonly infected fish can be estimated. Estimates of L∞ are obtained for orange roughy (Hoplostethus atlanticus), albacore tuna (Thunnus alalunga) and the New Zealand southern arrow squid (Nototodarus sloanii).

Description: This chapter records the benthonic foraminifera associated with a biogenic gas seep in the North Sea. A sample from an actively seeping site contains a benthonic foraminiferal assemblage statistically distinct from that of a control site. The distinctions are in terms of, firstly, abundance, diversity and dominance, secondly, taxonomic composition, and thirdly, proportions of epifaunal (surface-dwelling) and infaunal (sediment-dwelling) morphotypes.

Description: Turbulence in the Planetary Boundary Layer has been a topic of research for a long time. Its theory, however, is hampered by the fact that we have fewer fundamental equations than unknowns when dealing with turbulent motions. The search for additional “laws” to match the number of equations with the number of unknowns in turbulence theory is commonly labelled the turbulent closure problem. Despite considerable effort, this problem has not been solved. There is a variety of approaches available. However, these have not converged towards a commonly accepted PBL theory, like the Monin-Obukhov similarity for the surface layer. The Working Group on Boundary Layer Dynamics and Air-Sea interaction of ICDM/IAMAP therefore invites the scientific community to discuss these problems and possible solutions. The present paper intends to stimulate such a discussion.

Description: The objective of the study was to produce a size-based matrix model of a Laminaria digitata (L.) Lamour. population. ‘Hard’ data for insertion in the matrix were collected in a 9 year cohort analysis of size and age specific survival and fertility for a stand in south west Nova Scotia, Canada. The product of the square matrix containing these values and a column vector containing the densities of size classes was used to project the size class structure one year later. The projected estimates were found to fit empirical estimates with some confidence. In contrast, an age-based fertility life table wrongly predicted a population declining in density by 45% per year. The study supports, in theory, the use of size-based matrix models for management of harvested stands. In reality, the amount of work required to obtain ‘hard’ data and the site specific nature of the projections may preclude the use of such an approach to broad scale management.

Description: Die häufigsten vulkanischen Volatilen sind H2O, CO2, SO3 und Halogene. Zusammensetzung, Menge und Injektionsraten von vulkanischen Gasen und Partikeln in die Troposphäre und Stratosphäre hängen ab von der chemischen Zusammensetzung eines Magmas, dem plattentektonischen Milieu sowie Eruptionsmechanismen und Eruptionsraten. Über 90% der eruptierten Magmen sind basaltischer Zusammensetzung mit niedriger Viskosität, relativ geringen Volatilengehalten und meist niedrigen Eruptionsraten sowie wenig explosiven Eruptionen überwiegend entlang der mittelozeanischen Rücken in großen Wassertiefen. Magmen in Inselbögen und Subduktionszonen an Kontinenträndern sind H2O-reich, in anderen plattentektonischen Milieus überwiegt in basaltischen Magmen CO2. In mafischen Magmen ist CO2 schlecht löslich und kann daher schon mehrere Kilometer unter der Erdoberfläche als Gasphase aus einem Magma entweichen. Felsische (hochdifferenzierte) Magmen, H2O-reich und CO2-arm, eruptieren oft hochexplosiv, insbesondere an Subduktionszonen, und mit hohen Eruptionsraten, z.B. El Chichón (Mexiko, 1982) und Pinatubo (Philippinen, 1991). Ihre Eruptionssäulen (Gas-/Partikelgemische) können bis ca. 40 km Höhe erreichen und sind Hauptlieferant der in die Stratosphäre injizierten Gasmengen.

Description: In the subtropical belt highly productive ecosystems are formed by coral reefs in oligotrophic seas. Towards more eutrophic conditions, coral reefs diminish and are subsequently replaced by highly productive kelp forests. In high latitudes framework constructing carbonate production is enhanced by the growth of branching coralline algae which predominantly generate maerl-type deposits. On a global view, these coralline algal ecosystems show an island-like distribution pattern within the phaeophytic kelp belt. Compared to kelp ecosystems, coralline-algaldominated ecosystems have low rates of productivity. Therefore, it is reasonable to seek the pronounced competitive value of the extremely slow-growing corallines. Due to their low annual growth increment, the coralline algae studied are very endangered by abiotic physical disturbances and by overgrowth of rapidly growing filamentous algae or sessile invertebrates. To overcome fouling pressure and storm-triggered physical disturbances, coralline algae thrive well in wave-sheltered headlands or skerry areas and generate characteristic ‘denuded areas’ by intense herbivory. This general distributional pattern is also true for high-boreal to subarctic coralline algal bioherms in northern Norway. Such a complex biological feedback maintains a high potential of self-regulation or self-organization in the algal reef bioherms. The different proponents involved in feedback processes include bacterial colonization, diatom microfouling and selective induction of larval metamorphosis. The negative impact of diatom microfouling and the important role of herbivores are relevant activities in the feedback system on a microscopic scale. Macroscopically, intense herbivory on coralline algae create denuded conditions, which are a widespread phenomenon in coralline algal ecosystems.

Description: Paragenetic mineral assemblages have been established based on mineralogical, chemical, and isotope (S, Pb) studies, and the sequence of deposition has been defined in hydrothennal sulfide structures in a typical back-arc basin. The ores in the Manus basin have a prominent Zn specialization (sphalerite, würtzite, and fe-sphalerite). An association of Fe-spbalerite and galena with Ag sulfosalts is noted that is not characteristic of typical midocean ridge hydrothennal systems. The average 34S in the sulfide minerals is 3.5%o, which corresponds to the medium-temperature sphalerite stage in hydrothermal mineral fonnation. It is suggested that the metal source is located in the relatively acid rocks of the island-arc tholeiitic series and possibly in sediments.

Description: The Platanar volcanic center is dominated by a calc-alkaline, basalt-andesite-dacite-rhyolite magma series with unusual LREE enrichment. Adjacent and overlapping the calc-alkaline rocks are the most alkaline basalts found along the volcanic front of Central America. These basalts are mafic, LIL- and LREE-enriched transitional to alkaline basalts. Several are found on the north flank of Platanar in the Aguas Zarcas region, where there are nine cinder cones and a few isolated flows. However, they are also found in isolated lava outcrops at least as far south as Porvenir volcano along the volcanic front. The addition of mafic alkaline magmas with high La/Yb and low Ba/La into the Platanar magma chamber or chambers may contribute to the LREE-enriched character of the Platanar basaltic andesites and andesites. At Platanar the field and geochemical evidence suggest mixing between calc-alkaline and alkaline magmas, a process that has probably occurred throughout the development of the Cordillera Central of Costa Rica. The presence of negative Ce anomalies in several of the calc-alkaline lavas also make the Platanar complex very unusual compared to the rest of the Central American volcanic front. In the center of the Platanar complex is the Chocosuela caldera, an apparent remnant of an avalanche caldera created by the collapse in the Middle Pleistocene of an ancestral stratovolcano toward the NNW in a directed blast-type eruption. Rhyolite is present as pumice lapilli in pyroclastic flow deposits outside the caldera rim. Whole lapilli analyses span the daciterhyolite range. The previous eruption of high silica tephra as pyroclastic flows, the current long dormant period and the repeated occurrence of earthquake swarms on the flanks of the Platanar complex make it a candidate for volcanic hazard mapping, detailed geological mapping and emergency planning.

Description: Here we describe experiments aimed at developing an element-selective ion source for thorium (Th). The technique applied is resonance ionization spectroscopy (RIS) with a thermal atom beam. Ionization schemes for isotopically nonselective ionization of Th as well as for isotopically selective ionization of 230Th are proposed. The RIS-scheme used is two-photon two-colour ionization with excitation in the ultraviolet spectral range between 244 nm and 267 nm or in the visible spectral range between 485 nm and 529 nm. Ionization of the excited atoms is performed either by ultraviolet photons or by visible photons, depending on the energy required for this process.

Description: The spatial distribution and species composition of high-Antarctic ichthyonekton was investigated during the EPOS 3 cruise by RV Polarstern in the eastern Weddell Sea during January–February 1989. A multiple rectangular midwater trawl was used to collect samples from the surface to near the sea floor at 11 stations along a 245 kra transect off Halley Bay. Early larval stages of 18 species, representing about 24% of the known Weddell Sea ichthyofauna, were present in the water column. The Antarctic silver-fish, Pleuragramma antarcticum, over-whelmingly dominated the catches comprising 84.5% of the 5022 specimens caught. The abundance of this species markedly increased towards the offshore end of the transect with the highest numbers occurring near the shelf-break front associated with the westerly current of the southern limb of the Weddell Gyre. The increased abundance of P. antarcticum in continental slope waters was attributed to deflection of the East Weddell Coastal Current beyond the shelf/slope break by fringing ice shelves. Most larval and juvenile fish were found in the seasonally warmed upper 0–70 m layer of the Antarctic Surface Water where conditions occurred that appeared to be favourable to both feeding and growth. Cluster analysis indicated that inner-, central-and outer-shelf assemblages were represented and that the species composition was most effectively described by reference to water mass and depth.

Description: Coral reef bleaching, the whitening of diverse invertebrate taxa, results from the loss of symbiotic zooxanthellae and/or a reduction in photosynthetic pigment concentrations in zooxanthellae residing within the gastrodermal tissues of host animals. Of particular concern are the consequences of bleaching of large numbers of reef-building scleractinian corals and hydrocorals. Published records of coral reef bleaching events from 1870 to the present suggest that the frequency (60 major events from 1979 to 1990), scale (co-occurrence in many coral reef regions and often over the bathymetric depth range of corals) and severity (〉95% mortality in some areas) of recent bleaching disturbances are unprecedented in the scientific literature. The causes of small scale, isolated bleaching events can often be explained by particular stressors (e.g., temperature, salinity, light, sedimentation, aerial exposure and pollutants), but attempts to explain large scale bleaching events in terms of possible global change (e.g., greenhouse warming, increased UV radiation flux, deteriorating ecosystem health, or some combination of the above) have not been convincing. Attempts to relate the severity and extent of large scale coral reef bleaching events to particular causes have been hampered by a lack of (a) standardized methods to assess bleaching and (b) continuous, long-term data bases of environmental conditions over the periods of interest. An effort must be made to understand the impact of bleaching on the remainder of the reef community and the long-term effects on competition, predation, symbioses, bioerosion and substrate condition, all factors that can influence coral recruitment and reef recovery. If projected rates of sea warming are realized by mid to late AD 2000, i.e. a 2°C increase in high latitude coral seas, the upper thermal tolerance limits of many reef-building corals could be exceeded. Present evidence suggests that many corals would be unable to adapt physiologically or genetically to such marked and rapid temperature increases.

Description: The fish component in the diet of Antarctic fur seals, Arctocelaphus gazella, was investigated at Laurie Island, South Orkney Islands from mid January to April 1988. Fish otoliths occured in 78.8% of faecal droppings. Most of the otoliths extracted from scats belonged to Myctophid fish (93.4%), mainly Electrona antarcitca and Gymnoscopelus nicholsi. These two fish species thus constituted the bulk of the diet. A greater percentage of the otoliths from G. nicholsi (31.1%) in this study were considered suitable for measurement in comparison with 10.3% from scats at Heard island in 1990 and 11.4% atMacquarie Island in 1988/98. This lesser degree of erosion would suggest that foraging areas of fur seals during this study were closer to land than during previous studies. During the period studied, the commercial fishery around the South Orkneys was not based on Myctophid fish so there was no direct competition for fish between the fur seals and fisheries.

Description: This paper concludes a collection of contributions presented at the 8th Workshop of the International Association of Phytoplankton Taxonomy and Ecology. It derives a consensus as to the virtues and strengths of J. H. Connells Intermediate Disturbance Hypothesis (IDH), its applicability to phytoplank- ton ecology and its theoretical and practical weaknesses. The view is expressed that the IDH is too useful a concept to reject and that, as a word model, it provides a powerful link between diversity and dis- turbance. The more robust investigations that are necessary to consolidate the tenancy of IDH need to concentrate upon the separation and quantification of the stimulus- and response-components of dis- turbance.

Description: Phytoplankton diversity was studied in two North German lakes of comparable nutrient chemistry but different exposure to winds. In both lakes, phytoplankton was primarily N-limited but diatoms were Si-limited. Plußsee had a very constant mixing depth during summer, while week-to-week changes of several meters were quite common in the more exposed Behler See. In Plußsee, phytoplankton biomass during summer came closer to the carrying capacity as defined by the available total N. In Plußsee there was a marked decline of diversity during the summer maximum of biomass, while this decline was less pronounced in Behler See. It is concluded that disturbances which prevented phytoplankton from reaching the carrying capacity also maintained a high level of diversity. A negative response of diversity to undisturbed conditions became apparent, after phytoplankton biomass had exceeded about 5% of the carrying capacity.

Description: In Lake Constance, after several decades of cutrophication, a decrease in phosphorus loading over the last decade has lead to a partial recovery from eutrophication. Here we analyse the shift in the taxonomic composition of phytoplankton during the first decade of oligotrophication in Lake Constance. During the 1980s, spring total P concentrations decreased from ca. 130 to less than 50 mgr·l–1. This decrease was reflected by an approximately proportional decrease in summer phytoplankton biomass while spring phytoplankton biomass seemed unresponsive. Major taxonomic changes occured during both growth seasons. In spring, the proportion of diatoms, green algae and Chrysophyta increased while the proportion of Cryptophyta decreased. The summer trend was very different: the relative importance of diatoms decreased and Cryptophyta and Chrysophyta increased, while Chlorophyta reached their peak around 1985. These trends are also analysed at the genus level. Comparison with taxonomic trends during the eutrophication period shows the expected reversals in most cases. Comparison with other lakes shows general similarities, with the notable exception that Planktothrix rubescens has never been important in Lake Constance. The increase of diatoms during spring is attributed to their improved competitive performance with increasing Si:P ratios. Their decrease during summer is explained by the increasing silicate removal from the epilimnion by increasing spring populations.

Description: This paper introduces a collection of contributions presented at the 8th Workshop of the International Association of Phytoplankton Taxonomy and Ecology. It compares the substance of with what to limnologists is the more familiar lsquoparadox of the planktonrsquo posed by G. E. Hutchinson. The utility of Connell's Intermediate Disturbance Hypothesis in plankton ecology is, potentially, more instructive but inherent difficulties in relating response to stimulus have to be overcome. A copy of the brief distributed to contributors before the workshop is appended.

Description: Despite extensive discussions during the last 20 years stromatolites are still used by many geologists as unequivocal indicators of very shallow-water conditions. We investigated four stratigraphic units from the Lower and Middle Jurassic of southern Germany (Posidonien-Schiefer, Amaltheen-Ton) and of the Northern Calcareous Alps (Adneter Kalk, Klauskalk), which were formerly interpreted as shallow marine sediments by some authors due to the occurrence of stromatolites. Our interpretations of the macro-, micro- and ultrafacies of these sediments are not compatible with shallow-water settings. We therefore propose a deep-marine, aphotic origin of these stromatolites. Former interpretations of the Posidonien-Schiefer as a shallow-water deposit are mainly based on the occurrence of stromatolites. We favour the model of a temporarily stagnant, deep, aphotic basin for these planktonrich sediments. Particles resembling ooids, but lying within mudstones cannot be taken as evidence for shallow agitated water. They either formed within the mud or are allochthonous. The deep-water setting of the red limestone of the Alpine Early and Middle Jurassic is indicated by a lack of platform-typical components like coated grains and phototrophic benthos and by shells of plankton and nekton forming a major part of the sediment. Stromatolites occur on the steep slope of a drowned Rhaetian reef with an estimated relief of 50–100 m and immediately below and within radiolarian limestones, deposited below the aragonite compensation depth (ACD). The aphotic stromatolites show some morphological differences to their shallow water counterparts. In all of our sections they occurred during intervals of reduced sedimentation. They form only thin horizons and probably grew very slowly. Mineralizations by Fe−Mn oxides and phosphate are very common. The presence of a microbial film is evident from binding of sedimentary particles, but the nature of the microbes is not known. Growth habits within the very distinct environments of red limestone and black shales show some common features, but also clear differences. The microproblematicum Frutexites Maslov is a very common component in deep-water stromatolites, but may also itself form small crusts or dendrolites. It occurs in two different forms. Opaque, slender forms with indistinct outlines probably grew within the weakly lithified sediment. Thicker, transparent forms with well defined outlines are found in cavities and probably also grew on the seafloor. Well preserved specimens display an internal fabric of radially arranged fibres of Fe−Mn oxides and calcite. It is suggested that calcite or aragonite were one original mineralogy ofFrutexites, which was later replaced by Fe−Mn oxides or phosphate. It is not certain whether Frutexites is an organic, biomineralized structure or an inorganic mineralization, but the variable mineralogy and growth forms in different environments point to an organic origin. But even if organic, the occurrence in cryptic habitats and negative phototactic growth-directions make it clear that Frutexites was not phototrophic

Description: Klimawirkungsforschung untersucht die Auswirkungen von Klimaänderungen hinsichtlich ökologischer und zivilisatorischer Effekte auf den Menschen und seine Umwelt durch Erarbeitung von Handlungsstrategien. Dieser Statusbericht vermittelt einen Einblick ins Treibhaus aus verschiedenen Blickwinkeln: auf den globalen und regionalen Wandel, als Blick zurück in das geologische Archiv sowie auf die Klimaauswirkungen, auf die Hydro-Morphodynamik und Küstensicherheit, auf die Flora und Fauna, auf Ökosysteme und Stoffkreisläufe sowie auf sozio-ökonomischer Ebene am Beispiel der südlichen Nord- und Ostsee. Küsteningenieure, Geographen und Raumplaner, Geologen, Biologen, Klima-, Sozial- und Wirtschaftsforscher sowie Verantwortliche in den Küstenverwaltungen erhalten einen bisher nicht verfügbaren Überblick über die Zusammenhänge des globalen Wandels an diesem konkreten Raumbeispiel.

Description: Samples of the squid Martialia hyadesi were collected aboard two Japanese squid-jigging vessels carrying out commercial fishing trials at the Antarctic Polar Frontal Zone, north Scotia Sea, in February 1989. The dissected stomachs of 61 specimens were classified according to fullness and the contents were examined visually. Identifiable food items included fish sagittal otoliths, crustacean eyes, the lappets on euphausiid first antennule segments and cephalopod sucker rings. The most frequent items in the squid's diet were the myctophid fishes Krefftichthys anderssoni and Electrona carlsbergi, the euphausiid Euphausia superba and a hyperiid amphipod, probably Themisto gaudichaudi. A small proportion of the sample had been feeding cannibalistically. Total lengths of the fish prey were estimated from sagittal otolith size using published relationships. All fish were relatively small; 7 to 35% of squid mantle-length. However, it is possible that some heads of larger fish are discarded by the squid and so are not represented by otoliths in the stomach contents. Over the size range of squid in the sample there was no relationship between size of fish prey and size of squid. Similarly, when the squid sample was divided into groups according to prey categories: crustaceans, crustaceans+fish, fish, cephalopod, there was no evidence that dietary preference was related to squid size. The prevalence of copepod-feeding myctophids in the diet of this squid, which is itself a major prey item of some higher predators in the Scotia Sea, suggests that a previously unrecognised food chain: copepod-myctophid-M. hyadesi-higher predator, may be an important component of the Antarctic oceanic ecosystem.

Description: The diet of the Wandering Albatross at Subantarctic Marion Island was studied by inducing recently fed chicks to regurgitate and by stomach flushing adults about to feed chicks. Liquid comprised 70.2% of stomach content mass recovered from chicks. Solid material comprised cephalopods (58.6% by mass), fish (36.5%) and crustacean, cetacean and seabird material as minor items. Twenty-three taxa of cephalopods were identified, the onychcteuthid squid Kondakovia longimana being the most important. Estimated average mass of squid was 694 g with a maximum of over 8 kg. Diet of the Wandering Albatross at Marion Island was broadly similar to that at other studied localities. The high proportion of cephalopods known to float after death in the diet, and the deep-water habits of the few fish identified, suggest that scavenging plays an important role in foraging behaviour.

Description: The reproductive strategy of the cirrate octopods Opisthoteuthis agassizii and O. vossi (collected off Namibia from 1988 to 1990) was analyzed. Ovarian oocyte size frequency analysis for both species revealed continuous egg production over the entire adult life span. Mature eggs were stored in the single oviducal gland and distal oviduct, but oviducal gland fullness was not related to body size (p〉0.2). All O. agassizii male specimens from 95 to 5400 g total weight were sexually mature, as were all females from 190 to 1650 g, indicating that considerable growth takes place after the onset of sexual maturity. “Continuous spawning” is defined as a single, extended and continuous period of egg maturation and spawning. This model of reproductive strategy is previously unreported in cephalopods. All O. vossi male specimens from 750 to 3050 g total weight, and females from 800 to 1300 g, were sexually mature. Mature males and females of both species were collected in all seasons of the year. The adaptation of cirrate octopods to non-scasonal deep-sea environments is considered. The sexual maturity characteristics of males were analyzed, and examination of the spermatophore revealed opercular structures previously unreported in cephalopods. For females, the micropyle of the eggs are described and the mineral analysis of the egg shell disclosed that sulphur was the major element present.

Description: Turbulent fluxes have been measured in the atmospheric surface layer from a boom extending upwind from the Dutch offshore research platform Meetpost Noordwijk (MPN) during HEXMAX (Humidity Exchange over the Sea Main Experiment) in October–November, 1986. We started out to study eddy flux of water vapour, but discrepancies among simultaneous measurements made with three different anemometers led us to develop methods to correct eddy correlation measurements of wind stress for flow distortion by nearby objects. We then found excellent agreement among the corrected wind stress data sets from the three anemometers on the MPN boom and with eddy correlation measurements from a mast on a tripod. Inertial-dissipation techniques gave reliable estimates of wind stress from turbulence spectra, both at MPN and at a nearby ship. The data cover a range of wave ages and the results yield new insights into the variation of sea surface wind stress with sea state; two alternative formulas are given for the nondimensional surface roughness as a function of wave age.

Description: In tropical and subtropical regions of the world, jellyfish stings cause fatalities by means of venom injecting nematocysts. For nematocyst discharge an adequate combination of chemical and mechanical stimulation is required. In order to test whether skin care products can protect against nematocyst discharge, we tested two sunscreens and one lotion applied to pieces of live human skin and exposed them to Cyanea capillata tentacles. (Test specimens were collected in 1990 along the shore of Rømø, Denmark and in the Flensburger Förde.) The fine structure analysis of the cnidom of C. capillata showed a high grade of variation in shape and size. The basic distinctive characteristic for stomocnides and astomocnides, the terminal opening at the tubule tip, could not be found. The identification of spines at the basal tubule of atrichous isorhizas suggested that these should be characterized as basitrichous isorhizas. An association between nematocyst morphology and a special function such as penetration or entanglement was not observed. All nematocyst types penetrated unprotected skin. Parafilm (an inert material) and unprotected skin substrates served as controls. The discharged nematocysts on the skin and Parafilm surfaces were counted using scanning electron microscopy. The percentage of discharged nematocysts on test substance protected skin surfaces ranged from only 7.7 to 38.2%, compared to 100% on the unprotected control skin. In addition to this marked reduction in nematocyst discharge, the relatively few discharged nematocysts on protected skin showed malfunctions, and the injection of venom would have failed because the tubules of the nematocysts did not penetrate the skin. The results indicate a general possibility that human skin may be protected against nematocyst discharge of jellyfish with the application of sunscreen or lotion.

Description: Samples of the squid Martialia hyadesi were collected aboard two Japanese squid-jigging vessels carrying out commercial fishing trials at the Antarctic Polar Frontal Zone, north Scotia Sea, in February 1989. The dissected stomachs of 61 specimens were classified according to fullness and the contents were examined visually. Identifiable food items included fish sagittal otoliths, crustacean eyes, the lappets on euphausiid first antennule segments and cephalopod sucker rings. The most frequent items in the squid's diet were the myctophid fishes Krefftichthys anderssoni and Electrona carlsbergi, the euphausiid Euphausia superba and a hyperiid amphipod, probably Themisto gaudichaudi. A small proportion of the sample had been feeding cannibalistically. Total lengths of the fish prey were estimated from sagittal otolith size using published relationships. All fish were relatively small; 7 to 35% of squid mantle-length. However, it is possible that some heads of larger fish are discarded by the squid and so are not represented by otoliths in the stomach contents. Over the size range of squid in the sample there was no relationship between size of fish prey and size of squid. Similarly, when the squid sample was divided into groups according to prey categories: crustaceans, crustaceans+fish, fish, cephalopod, there was no evidence that dietary preference was related to squid size. The prevalence of copepod-feeding myctophids in the diet of this squid, which is itself a major prey item of some higher predators in the Scotia Sea, suggests that a previously unrecognised food chain: copepod-myctophid-M. hyadesi-higher predator, may be an important component of the Antarctic oceanic ecosystem.

Description: Specimens of the squidAbralia veranyi were collected off the Bahamas in 1989. The bioluminescence of the ventral photophores was recorded on videotape at 11 to 12°C and 24°C, in conjunction with measurements of the spectral emission at the same temperatures. At 11 °C, the spectrum was unimodal, peaking at 490 nm with a narrow bandwidth. At the higher temperature a shoulder at about 440 nm appeared in the emission spectrum. The short, bright flashes from the subocular photophores had a broader bandwidth and a shorter wavelength emission maximum (475 nm) than that of the ventral photophores. Video recordings at the two temperatures showed no changes in either the identities of the luminescing photophores or their relative intensities. One structurally distinct type of photophore was not illuminated. We conclude that the observed spectral changes were produced within one group of photophores, and that recruitment of the unilluminated photophores would produce an additional spectral component, previously reported from another species ofAbralia (A. trigonura).

Description: The concentrations of 11 heavy metals (Ag, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn) were measured in the tissues (digestive gland, branchial hearts, gills, digestive tract, kidney, genital tract, muscle, skin, shell) of the two cephalopods Eledone cirrhosa (d'Orb.) and Sepia officinalis (L.) collected from the French coast of the English Channel in October 1987. The tissues of both species displayed a similar pattern of heavy-metal accumulation: the digestive gland, branchial hearts and kidney were the major sites of concentration for all 11 metals; the digestive gland accumulated silver, cadmium, cobalt, copper, iron, lead and zinc, the branchial hearts high concentrations of copper, nickel and vanadium, and the kidney high concentrations of manganese, nickel and lead. The digestive gland, which constituted 6 to 10% of the whole-animal tissue, contained 〉80% of the total body burden of Ag, Cd and Co and from 40 to 80% of the total body burden of the other metals. The ratios between heavy metal concentrations in the digestive gland and those in the muscle separated the elements into three groups, those with a ratio ≤10 (Cr, Mn, Ni, Pb, V, Zn), those with a ratio 〉10 to 〈50 (Co, Cu, Fe), and those with a ratio ≥50 (Ag, Cd). The digestive gland of cephalopods (carnivorous molluscs whose age can be easily calculated with great accuracy) would seem to constitute a good potential indicator of heavy metal concentrations in the marine environment.

Description: Adélie penguins (Pygoscelis adeliae) carrying dummy instruments were used to determine field metabolic rates using double-labelled water. All penguins injected with double-labelled water showed a marked loss of body mass (-4.5%) during the period of the experiments (20–131 h), irrespective of the time of the breeding season. Total body water averaged 57.3% and water flux estimates of field metabolic rates correlated with double-labelled water estimates of field metabolic rate (r2=0.68), indicating that Adélie penguins do not ingest significant amounts of sea water. Brooding Adélie penguins had a mean field metabolic rate of 10.1 W·kg-1 and at sea a field metabolic rate of 13.3 W·kg-1, both of which compare well with previously published estimates based on time/activity budgets and respirometry. Mean field metabolic rate in penguins with crèching chicks was 14.1 W·kg-1, and the birds spent 65 h absent from the nest as opposed to previous estimates of 7.1 W·kg-1 and 21 h. The effects of weather, disturbance and manipulation on the behaviour and field metabolic rate of penguins late in the breeding season are discussed. Adélie penguins (crèching chicks) equipped with externally attached instruments spent more time absent from the nest than noninstrumented controls (76 vs 54 h), but had a lower field metabolic rate.

Description: The effect of spray droplets in the marine surface layer on evaporation is considered. Independent evidence from energy constraints, from visibility and from sea salt content of air is used. The estimation shows that, except perhaps for hurricane wind strength, the increase of total evaporation from evaporating droplets is negligible. This is in agreement with recent experimental evidence.

Description: The location of spawning grounds of the squid Loligo vulgaris reynaudii (D'Orbigny) was investigated in the years 1988–1990. At least 39 spawning sites were found during this period along the inshore areas of the Eastern Cape coastline between Algoa Bay and Plettenberg Bay. The substrate chosen for egg laying was mostly fine sand or flat reef, frequently in large and relatively shettered bays. Spawning was found to occur sporadically throughout the year, and some spawning sites were used repeatedly within a particular year and in subsequent years. Squid migrate in discrete schools separated by sex in the vicinity of the spawning sites; these schools mix during spawning. Mating and egg deposition behaviour is described from observations made on the spawning grounds. Cannibalism was seen on a number of occasions, but no post-spawning mortality was recorded. Egg beds consisted mostly of large concentrations of egg strands (〉3 m in diameter), with smaller aggregations of one to ten egg strands surrounding these, with single strands in the immediate vicinity. Three basic patterns of echotraces were identified and interpreted according to diving observations. These patterns were classified as loose patches, dense patches, and complex patterns. The first two represent non-spawning schooling patterns and the third, mating and egg laying behaviour. This observation led to the general classification of squid aggregations: schools (non-spawning mode) and concentrations (spawning mode). Concentrations as far as Loligo vulgaris reynaudii was concerned were further divided into two patterns: suprabenthic and benthic (spawning) squid.

Description: Locomotion and fin coordination of the only living crossopterygian fish Latimeria chalumnae were studied with submersibles in the fish's natural habitat at around 200 m depth off Grand Comoro, western Indian Ocean. Latimeria is a highly specialized predatory fish adapted for nocturnal drift hunting with good fast start capability. Twelve different forward movements and manoeuvres were found and described. The movements of the paired and unpaired fins were analysed. Propulsion was accomplished with downstrokes of the pectoral fins and right-left or left-right strokes of the unpaired lobed fins. The paired fins were not used for walking on the bottom. Swimming velocity, stroke amplitudes and stroke duration were analysed from films and videos taken in the wild. Stroke duration of the paired and unpaired lobed fins was similar and varies between 1.9 to 5.8 sec. Paired fins alternated synchronously. The coordination at approximately ø = 180° between opposite paired fins is stable and independent of locomotory pattern and velocity. A phase deviation of about 90°–100° exists between paired and unpaired fins. A model is developed that describes the functional implication of this deviation as a method of producing a steady swimming performance which smooths recoil movements and prevents rotation of the body. The novel slow and fast swimming mode of Latimeria is named in accordance with Breder's (1926) descriptive nomenclature as ‘coelacanthiform’. This study indicates a primary swimming function for the primitive sarcopterygian fin and confirms earlier evolutionary assumptions of a more open-water life style of coelacanth fishes. Paleoethological models of the walking habits of Latimeria have to be rejected. Synchronous alternation of paired fins originating from hydrodynamic demands could be a pre-adaptation and a shared derived character in sarcopterygian fishes that facilitated the fish-tetrapod transition.

Description: Sediment cores from the Central Pacific Basin were studied to determine (a) stratigraphic hiatuses, (b) sedimentation rates, and (c) their relationship to topography and the occurrence of deep-sea manganese nodules. The results of core studies and of detailed examination of two selected areas in the Central Pacific Basin led to the following conclusions. (1) Hiatuses of Neogene through Quaternary age occur widely in the Central Pacific Basin. A close relationship exists between the distribution pattern of the hiatuses and areas of low sedimentation rate, indicating the strong influence of a bottom current on sedimentation processes. (2) The hiatuses within the cores are dated as late Miocene, late Pliocene, and latest Pliocene to early Pleistocene. (3) The areas where the hiatuses are most common, and where sedimentation rate varies locally, are divided into two types: topographic highs in flat basin plains (“abyssal hill type”), and narrow, elongated topographic lows (“valley type”). They show different styles of sedimentation and hiatus formation related to the intensity of bottom current. (4) Local variation in the style of occurrence of manganese nodules depends on the relative importance of the bottom current. The differences in the manganese nodule types (r- and s-types) reflect the chemical environment where nodules have been formed. The r- and s-type nodules are related to poorly oxygenated and well oxygenated environments, respectively. Sedimentation rate is the main control on the chemical environment and nodule characteristics, determining the positions of nodule growth in the vicinity of the water-sediment interface; sedimentation rate varies inversely with the support strength of the surface sediments.

Description: Lipopolysaccharides were isolated from the moderate halophilic Ectothiorhodospira shaposhnikovii slight to and Ectothiorhodospira mobilis and from the extremely halophilic Ectothiorhodospira halophila by the hot phenol-water and purified by the phenol-chloroform-petroleum ether methods. The isolated lipopolysaccharides of all three species contained 3-deoxy-d-manno-octulosonic acid and d-glycero-d-mannoheptose indicating the existence of a core. They contained additionally glucose and uronic acids (E. shaposhnikovii and E. mobilis) or glucose, uronic acids and threonine (E. halophila). Sodium deoxycholate gel-electrophoresis of the three lipopolysaccharides, each showing only one major band, indicated R-type character of the lipopolysaccharides of the three Ectothiorhodospira species. The lipid A fractions of the lipopolysaccharides from E. shaposhnikovii and E. mobilis represented phosphorylated “mixed” lipid A types with both 2,3-diamino-2,3-dideoxy-d-glucose and d-glucosamine. The lipid A from E. halophila contained also phosphate and 2,3-diamino-2,3-dideoxy-d-glucose but only traces of d-glucosamine, which would indicated lipid ADAG. The fatty acid spectra were characterized by amide-bound 3-OH-10:0 and 3-OH-12:0 (E. shaposhnikovii), 3-OH-10:0 (E. mobilis), or 3-OH-10:0,3-OH-14:0, and 3-oxo-14-0 (E. halophila). The predominant ester-bound fatty acids were 14:0 and 16:0 (E. shaposhnikovii and E. mobilis), or 12:0 and 14:1 (E. halophila).

Description: The 14.1 Ma composite welded ignimbrite P1 (45 km3 DRE) on Gran Canaria is compositionally zoned from a felsic lower part to a basaltic top. It is composed of four component magmas mixed in vertically varying proportions: (1) Na-rhyolite (10 km3) zoned from crystal-poor to highly phyric; (2) a continuously zoned, evolved trachyte to sodic trachyandesite magma group (6 km3); (3) a minor fraction of Na-poor trachyandesite (〈1 km3); and (4) nearly aphyric basalt (26 km3) zoned from 4.3 to 5.2 wt% MgO. We distinguish three sites and phases of mixing: (a) Mutual mineral inclusions show that mixing between trachytic and rhyolitic magmas occurred during early stages of their intratelluric crystallization, providing evidence for long-term residence in a common reservoir prior to eruption. This first phase of mixing was retarded by increasing viscosity of the rhyolite magma upon massive anorthoclase precipitation and accumulation. (b) All component magmas probably erupted through a ring-fissure from a common upper-crustal reservoir into which the basalt intruded during eruption. The second phase of mixing occurred during simultaneous withdrawal of magmas from the chamber and ascent through the conduit. The overall withdrawal and mixing pattern evolved in response to pre-eruptive chamber zonation and density and viscosity relationships among the magmas. Minor sectorial variations around the caldera reflect both varying configurations at the conduit entrance and unsteady discharge. (c) During each eruptive pulse, fragmentation and particulate transport in the vent and as pyroclastic flows caused additional mixing by reducing the length scale of heterogeneities. Based on considerations of magma density changes during crystallization, magma temperature constraints, and the pattern of withdrawal during eruption, we propose that eruption tapped the P1 magma chamber during a transient state of concentric zonation, which had resulted from destruction of a formerly layered zonation in order to maintain gravitational equilibrium. Our model of magma chamber zonation at the time of eruption envisages a basal high-density Na-poor trachyandesite layer that was overlain by a central mass of highly phyric rhyolite magma mantled by a sheath of vertically zoned trachyte-trachyandesite magma along the chamber walls. A conventional model of vertically stacked horizontal layers cannot account for the deduced density relationships nor for the withdrawal pattern.

Description: An intercomparison is undertaken of the tropical behavior of 17 coupled ocean-atmosphere models in which at least one component may be termed a general circulation model (GCM). The aim is to provide a taxonomy—a description and rough classification—of behavior across the ensemble of models, focusing on interannual variability. The temporal behavior of the sea surface temperature (SST) field along the equator is presented for each model, SST being chosen as the primary variable for intercomparison due to its crucial role in mediating the coupling and because it is a sensitive indicator of climate drift. A wide variety of possible types of behavior are noted among the models. Models with substantial interannual tropical variability may be roughly classified into cases with propagating SST anomalies and cases in which the SST anomalies develop in place. A number of the models also exhibit significant drift with respect to SST climatology. However, there is not a clear relationship between climate drift and the presence or absence of interannual oscillations. In several cases, the mode of climate drift within the tropical Pacific appears to involve coupled feedback mechanisms similar to those responsible for El Niño variability. Implications for coupled-model development and for climate prediction on seasonal to interannual time scales are discussed. Overall, the results indicate considerable sensitivity of the tropical coupled ocean-atmosphere system and suggest that the simulation of the warm-pool/cold-tongue configuration in the equatorial Pacific represents a challenging test for climate model parameterizations.

Description: Enzymatic activity and quantity of the protease trypsin were measured in individual herring larvae (Clupea harengus L.). The enzymatic activity assay was done using a fluorescence technique, and a radioimmunoassay was used for quantification of trypsin. The results are compared and the differences between the techniques discussed. Both methods gave similar results, as high or low values in trypsin quantity were reflected in high or low values of tryptic activity. Quantity and activity were linearly and positively correlated, but small differences between methods were found at the lowest detection limits. Both techniques reflect high variability between individual larvae.

Description: We used five transects radiating from the South Orkney Islands to describe the distribution and abundance of marine birds during three days in late summer 1983. We found elevated numbers of birds at most crossings of steep physical gradients (fronts), but species were not equally attracted to each front. Our data suggest that the fronts around the South Orkney Islands, especially the Weddell-Scotia Confluence, provide important foraging habitat for birds. Albatrosses and fulmars appeared to aggregate preferentially near fronts overlying the insular slope, whereas Chinstrap Penguins were most abundant over the shelf.

Description: From mid January to April 1988 a total of 105 faecal samples of non breeding male fur seals, Arctocephalus gazella, was collected at Mossman Peninsula, Laurie Island. Examination of scats containing prey remains showed that fur seals fed mainly on krill, occuring in 100% of samples but fish were also a common food item (78.8%). Myctophids constituted more than 90% of fish taken by fur seals. Squid beaks occured in 34.3% of scats, being more common in the autumn period.

Description: Abschnitt 2.6 Bohrlochgeophysik, 10 S.

Description: The moult fast in emperor penguin (Aptenodytes forsteri) chicks was studied during January 1990 at Drescher Inlet, eastern Weddell Sea. In early January feeding of the chicks had stopped and about 4,000–5,000 chicks were in the inlet. The number of starving chicks decreased rapidly until 26 January when all chicks had either left the inlet or died. Mean body mass loss of starving chicks was 257 g/day and the evaluated specific daily mass loss was 25 g/kg body mass. The critical body mass, i.e. the mass below which chicks die, during moulting starvation was estimated to be 4 kg. Mean body mass was higher and mass loss lower in chicks at more advanced moult stages. Chicks left the inlet before moult was completed, although the sea-ice was still stable.

Description: The areas of marine pollen deposition are related to the pollen source areas by aeolian and fluvial transport regimes, whereas wind transport is much more important than river transport. Pollen distribution patterns ofPinus, Artemisia, Chenopodiaceae-Amaranthaceae, and Asteraceae Tubuliflorae trace atmospheric transport by the northeast trades. Pollen transport by the African Easterly Jet is reflected in the pollen distribution patterns of Chenopodiaceae-Amaranthaceae, Asteraceae Tubuliflorae, andMitracarpus. Grass pollen distribution registers the latitudinal extension of Sahel, savannas and dry open forests. Marine pollen distribution patterns of Combretaceae-Melastomataceae,Alchornea, andElaeis reflect the extension of wooded grasslands and transitional forests. Pollen from the Guinean-Congolian/Zambezian forest and from the Sudanian/Guinean vegetation zones mark the northernmost extension of the tropical rain forest.Rhizophora pollen in marine sediments traces the distribution of mangrove swamps. Only near the continent, pollen ofRhizophora, Mitracarpus, Chenopodiaceae-Amaranthaceae, and pollen from the Sudanian and Guinean vegetation zones are transported by the Upwelling Under Current and the Equatorial Under Current, where those currents act as bottom currents. The distribution of pollen in marine sediments, reflecting the position of major climatic zones (desert, dry tropics, humid tropics), can be used in tracing climatic changes in the past.

Description: In den 1980er Jahren wurden umfangreiche Bestandsaufnahmen zur Formenvielfalt der Fischkrankheiten sowie der saisonalen und regionalen Fluktuation ihrer Befallsraten in deutschen Küstengewässern angestellt. Sowohl Formenvielfalt als auch viele der Befallsraten scheinen im Wattenmeer und insbesondere in den dortigen Flußmündungen größer zu sein als in Vergleichsgewässern. Drei “neue” Krankheitsformen werden vorgestellt: die nahrungsinduzierte Maulgranulomatose des Stints, die vermutlich durch Flexibacter-Bakterien verursachte Gelbe Pest des Kabeljaus und eine Fibrom des Steinpickers, in dem lentivirusähnliche Partikel nachgewiesen wurden. Das Schwergewicht der bisherigen Forschungsvorhaben lag auf dem Sammeln von Felddaten. Mangels experimenteller Arbeitsansätze müssen viele wichtige Fragen zur Bedeutung dieser Krankheiten daher heute noch unbeantwortet bleiben. So bleibt die Vermutung unbewiesen, daß ein Reihe von parasitenbedingten Krankheiten einen entscheidenden Beitrag zur natürlichen Sterblichkeit vor allem von jungen Nutzfischen im Wattenmeer liefert. Auch das komplizierte Wirkungsgefüge anthropogener und natürlicher Faktoren bei der Entstehung von Fischkrankheiten im Gebiet wird ohne gezielte experimentelle Arbeiten nicht aufzudecken sein. Das Auftreten von Gelber Pest, Ichthyophonus-Krankheit und lentivirusähnlichen Partikeln in Fischtumoren stellt ein beträchtliches Gefährungspotential für die deutsche Fischwirtschaft dar. Allgemein ist festzustellen, daß in Deutschland eine große Empfänglichkeit gegenüber Umweltproblemen auf dem Gebiet der Marinen Pathologie besteht. Die nationalen Forschungskapazitäten sind aufgrund anderer, meist kurzfristig angelegter Arbeitsschwerpunkte jedoch nicht ausreichend darauf vorbereitet, diese Probleme auch erfolgreich zu analysieren und zu bewerten. Als Konsequenz wird gefordert, der bislang vernachlässigten Grundlagenforschung auf dem Gebiet der Marinen Pathologie neben der reinen Datenerhebung auf See künftig eine größere Bedeutung zuzumessen. Das gilt insbesondere für experimentelle und für biochemisch- und mikroskopisch-diagnostische Arbeiten. Künftig auftretende Probleme werden nur dann rechzeitig zu bewerten und zu lösen sein, wenn sich ein ausreichend breit angelegtes und fundiertes Wissenspotential kontinuierlich weiterentwickeln kann.

Description: The present study demonstrates that a distinct land-associated community of mesopelagic micronekton exists around the Hawaiian Islands. This “mesopelagic-boundary community” replaces the oceanic mesopelagic community over bottom depths of approx 400 to 700 m and includes about 14 species of fishes, 5 of shrimps and 4 of squids. Similar species of the mesopelagic micronekton have been reported in association with other landmasses at the boundary between the oceanic mesopelagic realm and upper continental or island slopes. These species may form a cosmopolitan “mesopelagic-boundary community” which shows regional differences in taxonomic composition, abundance and diversity. Boundary communities, with populations which are both tightly constrained geographically and relatively accessible to shore-based research programs, offer unique opportunities for studying biological processes of the mesopelagic realm and the interactions between neritic and oceanic populations. Data is presented from three midwater and two neuston sampling projects undertaken around the main Hawaiian Islands between 1987 and 1989; additional evidence from the literature is also discussed.

Description: A seabird and mammal census was carried out in the north-eastern Weddell Sea during the austral winter of 1986. The German research icebreaker Polarstern operated in heavy pack ice along the Greenwich Meridian between the northern sea ice boundary and the Antarctic coast. Crabeater seals (Lobodon carcinophagus), minke whales (Balaenoptera acutorostrata), Adélie penguins (Pygoscelis adeliae), Antarctic petrels (Thalassoica antarctica) and snow petrels (Pagodroma nivea) were found to be more abundant in the vicinity of the submarine Maud Rise, about 700 km north of the continental margin, than in other areas of substantial ice cover traversed during that cruise. The aggregations of birds and mammals are expected to reflect aggregations of their principal food, krill (Euphausia superba) wintering underneath the ice cover. The distribution pattern of krill predators coincides with the course of a warm water belt upwelling near Maud Rise. This upwelling could induce local ice melting which in turn may result in an increased release of sea ice algae.

Description: In 1987 and 1989 coelacanths were observed for the first time in their natural habitat with the help of submersibles. Coelacanths were found between 150–253 m depth, their preferential depth seems to be around 200 m; the water temperature ranged between 16.5–22.8° C. During the day coelacanths aggregate in small non-aggressive groups in sheltered lava-caves. Caves might be a limiting factor for distribution. At night they leave the caves for hunting by drifting singly along the steep lava slopes. They migrate between different caves located within a large home range covering more than 8 km coastline. Coelacanths are site-attached, some for a period of at least 2 years. Our own observations and earlier catch records show that only the west coast of Grand Comoro is a suitable coelacanth habitat with more structural complexity and prey fish abundance than other coastlines of the island. From our survey we estimated a total coelacanth population off Grand Comoro to be 150–210 individuals; a saturated population would be 370–510 individuals. This small relict population seems to be stable. International protection of coelacanths against commercial interests is needed.

Description: We report first observations on social behavior ofLatimeria chalumnae in its natural environment at around 200 m depth in the Comoro Archipelago, Western Indian Ocean. Coelacanths aggregate in small nonaggressive groups in sheltered lava-caves. They live in open site-attached social systems with individuals occupying large overlapping home ranges of more than 8 km coastline, some for a period of at least 2 years.

Description: This paper describes (i) the Recent distribution pattern of various types of carbonate sediments in Troms county (northern Norway), and (ii) the onset of carbonate sedimentation after the final deglaciation of the Fennoscandian ice-shield. The distribution of major facies belts is strongly dependent on hydrographic and topographic constraints. The main bulk of carbonate deposits is derived from maerl-producing coralline algal biotopes that are restricted to the photic zone of waveprotected areas and influenced by tidal currents. Furthermore, extended mollusc and echinoderm-rich arenites are present in the area investigated. In deeper subtidal areas, terrigenous sediments of Late Weichselian to Early Holocene age are preserved. However, these are strongly influenced by later winnowing processes, generating a coquina lag deposit that serves as a secondary hardground for a diverse fouling community. The Holocene facies successions can be seen in several raised outcrops, containing the transition from glacigenic to Recent non-glacigenic depositional conditions. Autochthonous radiocarbon dated rhodolith banks, which mark the onset of carbonate sedimentation, yielded surprisingly young ages of 5,500 YBP. Around 5,500 YBP, present-day oceanographic and climatic conditions had already been firmly established. This time-lag can be explained with the behaviour of postglacial sea level fluctuations in the area. From 10,000 their cooperation in this project. We address our sincere thanks specifically to Prof. T.O. Vorren, Dr. M. Hald, Dr. B. Gulliksen, Dr. J. Hansen, Dr. J.J. Møller, Dr. E. Thomsen, and Dr. G. Corner for their dedicate help in organizing our field trips in Troms and for extensive scientific discussions. Special thanks to capitain K. Bendiksen for his patience and professional skill while operating the vessel ‘OTTAR’ in the skerry area even under bad weather conditions. S. Rasmussen and G. Ellingsen assisted during the cruises and very kindly introduced us to the Norwegian way of life. Special thanks to the two reviewers (Prof. Dr. W.-Ch. Dullo and anonymus) for their critical but constructive remarks. J. Welling and Dr. M. Kaminski improved the language of the final version of the manuscript. This project is part of the German Science Foundation’s main research program ‘Globale und regionale Steuerungsprozesse biogener Sedimentation”. Financial support was kindly provided by the Deutsche Forschungs-gemeinschaft (He 1671/1-1, 2).

Description: In the Atlantic sector of the Southern Ocean, data from vertebrate predators and commercial fisheries suggests that the distribution of the ommast rephid squid Martialia hyadesi is related to the Antarctic Polar Frontal Zone, but it spreads further to the north in some years (Rodhouse, in press). A mass stranding of M. hyadesi occurred on Macquarie Island in 1971 (O'Sullivan et al. 1983) suggesting that its distribution is c ircumpolar (Rodhouse and Yeatman 1990). However, apart from a single beak collected from the s tomach of a wandering albatross at Mar ion Island (Imber and Berruti 1981) its presence has not, until now, been confirmed in the Indian Ocean sector and in particular it is not included in the list of cephalopods from the Kerguelenian Province (Lu and Mangold 1978). M. hyadesi is a major prey item of the grey-headed albatross, Diomedea chrysostoma, and the southern elephant seal, Mirounoa leonina, at South Georgia (Rodhouse et al. 1990; Rodhouse et al., unpublished data) and is present in the diet o f several other predators in the Scotia Sea area including the wandering albatross, Diomedea exulans (Rodhouse et al. 1987) and the giant petrels, Macronectes halli and M. gioanteus (Hunter 1983). It occasionally occurs as a significant by-catch in the lllex argentinus fishery on the Pa tagonian Shelf and has been taken during commercial squid jigging trials in the Scotia Sea at the Antarctic Polar Frontal Zone (Rodhouse, in press). It appears to have potential for commercial exploitation in the sub-Antarctic waters of the Atlantic sector of the Southern Ocean (Rodhouse 1990). In view of the ecological importance of M. hyadesi to Antarctic predators, and the likelihood that it will be commercially exploited in the future, it is important to thoroughly establish its geographical range, and in particular to confirm its circumpolar distribution.

Description: Seit jeher will der Geologe wissen, aus welchem Material die Erde besteht, wie ihre Struktur aussieht und welche physikalischen, chemischen und biologischen Vorgänge dabei im Laufe der Erdgeschichte zusammengewirkt haben. Indessen muß er sich, wie alle Historiker, auch heute noch weitgehend damit bescheiden zu ermitteln, wie und wann etwas geschehen ist, und nicht, warum. Daran ist vor allem die Komplexität der Fragen schuld und die Schwierigkeit, einschlägig zu experimentieren.

Description: Factors influencing the fate of ice algae released from melting sea ice were studied during a R V Polarstern cruise (EPOS Leg 2) to the northwestern Weddell Sea. The large-scale phytoplankton distribution patterns across the receding ice edge and small-scale profiling of the water column adjacent to melting ice floes indicated marked patchiness on both scales. The contribution of typical ice algae to the phytoplankton was not significant. In experiments simulating the conditions during sea ice melting, ice algae revealed a strong propensity to form aggregates. Differences in the aggregation potential were found for algal assemblages collected from the ice interior and the infiltration layer. Although all algal species collected from the ice were also found in aggregates, the species composition of dispersed and aggregated algae differed significantly. Aggregates were of a characteristic structure consisting of monospecific microaggregates which are likely to have formed in the minute brine pockets and channels within the ice. Sinking rates of aggregates were three orders of magnitude higher than those of dispersed ice algae. These observations, combined with the negligible seeding effect of ice algae found during this study, suggest that ice algae released from the melting sea ice are subject to rapid sedimentation. High grazing pressure at the ice edge of the investigation area is another factor eliminating ice algae released during melting. Data presented here were collected during the European Polarstern Study (EPOS) sponsored by the European Science Foundation

Description: Zooplankton was sampled by a Rectangular Midwater Trawl (RMT 1 + 8) in Weddell Sea surface waters (0 to 300 m) between 66 and 78°S during austral summer (February – March 1983). Sixty-nine taxa including different developmental stages were considered and divided into 16 size classes between 〈1 and 〉39.5 mm length. Biomass was determined by taxon and size class for three different meso- and macroplankton communities in the oceanic region, on the northeastern shelf and on the southern shelf of the Weddell Sea. The highest biomass of 11.2 mg DW m−3 (3.4 g DW m−2) was found in the northeastern shelf community (70 to 74°S), where juvenile and adultEuphausia crystallorophias accounted for 3.7 mg DW m−3 (1.1 g DW m−2). Although not quantitatively sampled, early copepodite stages (CI to CIII) ofCalanoides acutus andCalanus propinquus ranked second with 2.7 mg DW m−3 (0.8 g DW m−2). Biomass in the northeastern shelf community was concentrated in the size ranges 1 to 4 mm and 19.5 to 39.5 mm. The oceanic community of the central Weddell Sea was dominated by copepods smaller than 5 mm, which made up half of the total oceanic biomass. The tunicateSalpa thompsoni (7.0 to 8.5 mm) was the dominant single species with 1.6 mg DW m−3 (0.5 g DW m−2). Euphausiids, mainly juvenile and adult krillEuphausia superba, comprised 1.2 mg DW m−3 (0.4 g DW m−2). Total standing stock in the oceanic community was 9.4 mg DWm−3 (2.8 g DW m−2). Lowest biomass values were found in the southern shelf community (south of 75°S) with 4.0 mg DW m−3 (1.2 g DW m−2), concentrated in the 1 to 4 mm and 14.5 to 34.5 mm size classes. Abundant species were the pteropodLimacina helicina (1 to 2 mm; 0.7 mg DW m−3; 0.2 g DW m−2) andE. crystallorophias (24.5 to 39.5 mm; 0.9 mg DW m−3; 0.3 g DW m−2). The data reveal that it is essential to distinguish among subsystems in the Southern Ocean. This leads to a better understanding of the structure and function of those pelagic food webs which represent alternatives to the paradigmatic krill-centered system.

Description: The dependence of results from coarse-resolution models of the North Atlantic circulation on the numerical advection algorithm is studied. In particular, the sensitivity of parameters relevant for climate simulations as e.g., meridional transport of mass and heat and main thermocline thickness is investigated. Three algorithms were considered: (a) a central difference scheme with constant values for horizontal and vertical diffusion, (b) an upstream scheme with no explicit diffusion, and (c) a flux-corrected transport (FCT) scheme with constant and strictly isopycnal diffusion. The temporal evolution of the three models on time scales of centuries is markedly different, the upstream scheme resulting in much shorter adjustment time whereas the central difference scheme is slower and controlled by vertical diffusion rather than advection. In the steady state, the main thermocline structure is much less diffusive in the FCT calculation which also has much lower heat transport. Both horizontal circulation and overturning in the meridional-vertical plane are strongest in the upstream-model. The results are discussed in terms of the effective vertical (diapycnal) mixing in the different models. A significant increase in vertical resolution would be required to eliminate the high sensitivity due to the numerical algorithms, and allow physically motivated mixing formulations to become effective.

Description: Planktonic foraminifera first appeared in the Early Jurassic, approx. 200 million years ago. They occurred in great abundance in the oceans only after an important marker Ievel of 130 million years (Early Cretaceous). Since that time, planktonic foraminifera are the most important first ranking Stratigraphie markers and indicators forachanging world's ocean. Knowledge of the ecological demands of living planktonic foraminifera help one to understand their environment in the past because of their high sensitivity to environmental changes; thus, they can be used to reconstruct the oceanic paleoclimate by means of their morphology, faunal assemblage and chemical composition.

Description: Predation among pelagic cnidarians and ctenophores is reviewed. The diets of semaeostome scyphomedusae and hydromedusae commonly include other gelatinous zooplanktivores. However, few species of siphonophores and ctenophores are known to consume other gelatinous species. Most of these species can be said to exhibit intraguild predation, since they consume species that potentially compete with them for food. In addition, some hydromedusan and ctenophore species may consume other gelatinous zooplanktivores exclusively. Characteristics of cnidarians and ctenophores as predators and as prey of other gelatinous species are discussed.

Description: Using bacteria that tolerate fairly high sodium sulphate concentrations and reduce sulphate and a coarse clay with buffering properties as solid electrolytes, biological fuel cells have been developed for providing electrical energy discontinuously. The biological active anodes, which accumulate fuel, contained a metal hydroxide catalyst that was converted during the biological process into a metal sulphide catalyst and functioned in a solidified aqueous electrolyte that contained sodium sulphate. The active carbon or titanium cathodes employed were activated with cobalt oxide spinels, molybdenum/vanadium compounds or metal chelates. When employed in continuous service for discontinuous energy consumption, fuel cells were capable of being operated with humus constituents or sugar waste as fuel over a period of 5 years without malfunction and maintenance. Positive results were achieved in the purification of waste-water with a modified type of fuel cell in which the production of energy was not dominant.

Description: A large-scale trawl survey in August 1989 and data from other surveys indicate that the mesopelagic zone (depth 200-500m) of the Sea of Okhotsk is most densely populated with squids, wit maximum catches of more than 500kg/h. The greatest concentrations occur above the continental slope, particularly in the northern TINRO basin and off the southwestern coast of Kamchatka, adjoining the most productive regions of the sea. Five squid associations are distinguished in terms of the makeup of the catches.

Description: The energy consumption of Adélie penguins while at rest in water (8.4 W·kg-1 at 4°C) or swimming below the surface was determined using a 21 m long canal fitted with respiration chambers at each end. Penguins chose to swim 86% of the time at speeds recorded in nature. Cost of transport was lowest (7.9 J·kg-1·m-1) at 1.7–2.3 m·s-1, corresponding to a power input of 15.8 W·kg-1, and only 50% as high as previously reported. Assuming a muscle efficiency of 0.25, propulsion efficiency is 0.4 and overall efficiency is 0.1. Calculated food requirements vary between 1060 g krill per adult and foraging trip at the beginning of the breeding season and 2500 g at the period of highest demand, prior to crèching of the chicks.

Description: Climatologists generally expect an anthropogenic global warming that could raise sea level 50-150 centimeters in the next century and more thereafter. One of the impacts would be the loss of coastal wetlands. Although the inundation of adjacent dry land would enable new wetlands to form, much of this land is or will soon be developed. If developed areas are protected, wetlands will be squeezed between an advancing sea and the land being protected, which has already happened in China and the Netherlands, where people have built dikes for centuries. Unlike those countries, the United States has enough land to accommodate the landward migration of wetlands; but governments lack the funds to purchase all the coastal lowlands that might be inundated and the legal authority to prohibit their development. We propose a third approach: allowing property owners to use coastal lowlands today as they choose, but setting up a legal mechanism to ensure that the land is abandoned if and when sea level rises enough to inundate it. Although compensation may be required, this approach would cost less than 1 percent as much as purchasing the land, and would be (1) economically efficient by enabling real estate markets to incorporate expectations of future sea level rise; (2) constitutional by compensating property owners; and (3) politically feasible by pleasing people who care about the long-term fate of the coastal environment without disturbing people who either are unconcerned about the distant future or do not believe sea level will rise. Because planning today would be more effective than reacting later, the U.S. government should develop a long- term strategy in the next three years.