bluuebunny/crossref_metadata_2025 huggingface dataset:
Epizoan Communities on Marine Turtles
Authors: Frazier J. , Margarttoulis D. , Muldoon K. , Potter C. W. , Rosewater J. , Ruckdeschel C. , Salas S.
Published: May 2008

Abstract. Marine turtles harbour a variety of epizoa, some of which are specific to these hosts, but shelled gastropod and bivalve mollusks were previously unrecorded on marine turtles. Thousands of turtles of five species from all major oceans were examined. Loggerheads, Caretta caretta, from Greece and the states of Georgia and Florida, USA, were the most remarkable hosts to mollusks. At least 15 species of bivalves and 5 species of gastropods were found on turtles. Many turtles hosting mollusks carried only one species and few individuals. Edible oysters, the most common molluscan epizoan on Grecian Loggerheads, may grow to more than 10cm in diameter, so in some cases the mollusks may survive for several years on the turtle. Large epizoan bivalves may in turn serve themselves as substrates for epizoa, molluscan or otherwise. There are no known obligate relationships between turtles and mollusks, although there may be a parasitic relationship between the Loggerhead turtle, a spirorchid blood fluke, and a gastropod intermediate host. It is unknown if turtles carrying mollusks are at a disadvantage.
Growth Dynamics in Posidonia oceanica (L.) Delile
Authors: Pirc Helmut
Published: May 2008

Abstract. Amounts of photosynthate in the rhizomes, in photosynthetically inactive basal parts of the leaves and different old leaf blades were examined. Winter leaf growth was supported by mobilisation of starch in the rhizome. This winter growth enables Posidonia oceanica to utilize the increased energy influx in early spring via the substantial leaf area already developed and to approach highest productivity in spring. During summer and autumn considerable concentrations of soluble carbohydrates were found in the leaves and rhizomes. Starch was stored in the rhizomes in concentrations of up to 6.8 % of dry weight. Levels of nitrogen and free amino acids were correlated with growth rates. The percentage of total nitrogen present as free amino acid‐nitrogen decreased from November (35 %) to summer (less than 1 %), by which time leaf growth had stopped. In contrast to this, amounts of organic anions were low in winter and spring and reached their maximum in summer.

Within a shoot, sites of leaf growth were characterized by high amounts of total nitrogen and free amino acids (innermost leaves), while carbon Fixation was highest in the leaves #2–#4. Particularly high concentrations of soluble carbohydrates were found midway along leaf blades.

It is evident that this unusual growth rhythm of Posidonia oceanica was only possible because of the ability to store considerable amounts of carbon and nitrogen in the rhizomes.

The results of this investigation demonstrate on the one hand that the chemical composition of the plant is strongly correlated with growth and production, and on the other hand that it is dependent on environmental factors, such as energy influx and temperature, which change with season.
Zooplankton Feeding Ecology: Contents of Fecal Pellets of the Copepod Anomalocera ornata from Continental Shelf and Slope Waters of the Gulf of Mexico
Authors: Turner Jefferson T.
Published: May 2008

Abstract. The diet of the copepod Anomalocera ornata was examined by comparing contents of fecal pellets produced on natural diets with assemblages of available phytoplankton. Samples were collected in continental shelf and slope waters of the northern Gulf of Mexico. A wide size and taxonomic array of phytoplankters was ingested, and remains of phytoplankton taxa in fecal pellets reflected the composition of phytoplankton assemblages in the water. Absence of crustacean remains in fecal pellets suggests that A. ornata feeds primarily as an opportunistic grazer.
The Zonation of Epiphytic Hydroids on the Leaves of Some Posidonia oceanica (L.) DELILE Beds in the Central Mediterranean
Authors: Boero F. , Chessa L. , Chimenz C. , Fresi E.
Published: May 2008

Abstract. The vertical zonation of the hydroid fauna associated with Posidonia oceanica leaves in three different localities of the central Mediterranean reveals the presence of two distinct communities. This depth‐related zonation shows patterns that are independent on the geographic area.
Tricellaria inopinata, n. sp., un nouveau Bryozoaire Cheilostome de la faune méditerranéenne
Authors: D'Hondt Jean‐Loup , Ambrogi Anna Occhipinti
Published: May 2008

Abstract. Tricellaria inopinata n. sp., is described from the lagoon of Venice. This is the first record of the genus Tricellaria from the Mediterranean Sea.

Description ?une espèce nouvelle de Bryozoaire, trouvée dans la lagune de Venise, dans un canal navigable, près du centre de la ville. Elle appartient au genre Tricellaria, dont la distribution connue est surtout boréale et indo‐pacifique. Bien que présente dans quatre stations seulement, cette espèce apparait bien installée dans la communauté qui colonise le biotope étudié.
The Estimation of Secondary Production of the Marine Bivalve Spisula subtruncata (DA COSTA) in the Area of the Po River Delta
Authors: Ambrogi Romano , Ambrogi Anna Occhipinti
Published: May 2008

Abstract. The secondary production of Spisula subtruncata (somatic production) is calculated in the framework of a benthic monitoring study in a coastal area. The temporal trends of density, biomass and growth increments are examined in the three year‐classes present. These are compared to certain physical and chemical parameters.
Alkaline Phosphatase Activity in the Red‐Tide Dinoflagellate, Ptychodiscus brevis
Authors: Vargo G.A. , Shanley E.
Published: May 2008

Abstract. Alkaline phosphatase activity (APA) was found in a nearshore, natural population of the red‐tide dinoflagellate Ptychodiscus brevis. Initial hydrolysis rates were enhanced by two orders of magnitude within 24 h upon addition of ammonium. Other nutrient (additions) or no additions also lead to a higher, although less pronounced increase in activity. Enhanced growth after nutrient additions combined with specific APA indicated that the bloom was both N and P limited. Since the natural population was a mixture of diatoms and the dinoflagellate, APA was also measured in unialgal cultures of P. brevis. APA was not reduced but enhanced by the addition of low concentrations of orthophosphate (0.5 and 1 μM). Higher orthophosphate concentrations (5 to 20 μM) reduced APA, although activity returned to control levels within 2 to 6h. Repression occurred within 30 sec after a 20 μM orthophosphate addition. Cells which had APA repressed by an orthophosphate addition regained their initial activity within 2 h after washing with phosphate‐free media. Phosphorus‐deficient cells of P. brevis possess an alkaline phosphatase system which is capable of continued activity at low in situ orthophosphate levels.
Polymorphic Zooids in Deitaic Species Populations of Conopeum seurati (CANU, 1928) (Bryozoa, Cheilostomata)
Authors: Poluzzi Angelo , Sabelli Bruno
Published: May 2008

Abstract. Deltaic populations of Conopeum seurati from diverse environmental settings have variable phenotypes related to strong competitive regimes and to dissolved oxygen minima. Under extremely stressful conditions, the poorly canalized phenotype of C. seurati displays new additional features such as kleistozooids (kleistós= closed) and chaotic celleporoid layers. Kleistozooids are clearly distinguishable polymorphs characterized by the presence of a compact, imperforate frontal membrane and by a strongly reduced lumen of the “opesium”. They commonly aggregate in clusters of regularly‐arranged individuals that store a large quantity of proteic material. The inferred function of these cell‐like structures is to supply nutrients for basic colony activities. Celleporoid layers are, possibly, a developmental relaxation of the colony of C. seurati for a more efficient use of space in competitive interactions.

Both celleporoid layers and kleistozooids reveal the magnitude of intracolony variability of a widespread opportunistic bryozoan species.
Chlorophyll in Copepod Faecal Pellets: Changes in Pellet Numbers and Pigment Content during a Declining Baltic Spring Bloom
Authors: Bathmann Ulrich , Liebezeit Gerd
Published: May 2008

Abstract. Zooplankton stock as well as faecal pellet numbers were monitored over 2 weeks during May in the central Baltic. Considerable changes in concentrations of chlorophyll and its derivates in copepod faecal pellets as well as in surface sediments were found during this period. The maximum concentration of 1.05 ngchl. a faecal pellet‐1, measured on 12 May, decreased by the end of the month to 0.08 ngchl. a faecal pellet‐1. This decrease was positively correlated with the disappearance of intact diatoms inside faeces. A flux of 1.53mgchl.a‐m‐2‐day‐1 via faecal pellets was calculated for the deep water layer (60–80 m) in mid May. This decreased to 0.005mgchl.a m‐2 day‐1 by the end of May. Chi. a accounted for up to 10 % of total pigments in samples from the top centimetre of the sediment surface. The means of transportation of faecal pellets as well as their function as a food supply to deeper ecosystems are discussed.
Growth, Production, and a Partial Energy Budget for the Amphipod, Talorchestia capensis (Crustacea; Talitridae) in the Eastern Cape, South Africa
Authors: SENUS P. VAN , MCLACHLAN A.
Published: May 2008

Abstract. .A population of Talorchestia capensis was sampled in dune slacks over the period of one year. Two hatching periods, one in March and one in September, were observed. Growth was rapid, the amphipods reaching a size of 8.4 mm standard length in 18 months. Maximum growth occurred in spring and minimum growth in winter. Annual mortality rates for summer‐ and winter‐hatched individuals were low, 0.22‐y“1 and 0.16‐y”1. Average production for the summer classes was 7.2g‐y˜‘ (dry mass) and for the winter classes 2.9‐y“1, with a P/B ratio of 2.25‐y”’. Production values peaked during autumn and summer. Abundance and biomass estimates showed maxima during summer and minima in early spring. Reproductive output was low, 0.1 kJ ? m‐2 y“1, indicating that 7 % of the total production is used for reproduction and 93 % for somatic production. The assimilated energy flow through the population was estimated to be 16.3 kJ m˜2 y˜‘ and consumption about 81.6 kJ m‐2 y_’.
Preliminary Observations on the Feeding Activity of Fishes during Tidal and Diel Cycles in the Loire Estuary: The Bib Trisopterus luscus L. 1758
Authors: ROBIN J. P. , MARCHAND J.
Published: May 2008

Abstract. .Series of experimental trawls repeated over the same area during both 12 and 24 h cycles coupled with an analysis of the stomach contents of the bib demonstrated quantitative and qualitative variations in the predator's diet. The population studied feeds continuously over 24 h, the coefficient of “fullness” is relatively constant, and freshly eaten prey can be observed both during the day and at night. The proportion of brown shrimp in the food increases after high tide, especially when this occurs at night, coinciding with the shrimp's period of maximum activity. However, the overall impact of the bib on the shrimp population depends more on the abundance of the former than on variations in their individual food intake.
Victims of Avicularia
Authors: WINSTON JUDITH E.
Published: May 2008

Abstract..The function of the sessile “trap‐door” avicularia of cheilostome bryozoans has been the subject of much speculation but relatively little observation. During studies of reef dwelling cheilostomes, avicularia of this type were seen to capture syllid polychaetes. This diverse group of small predatory worms, commonly found in the same habitats as bryozoan colonies, may be important factors in bryozoan ecology and evolution.
Size Selective Predation by the Asteroid Pisaster ochraceus on the Bivalve Mytilus calif ornianus: A Cost‐Benefit Analysis
Authors: Mcclintock James B. , Robnett Truman J.
Published: May 2008

Abstract. When simultaneously presented with equal numbers of four sizes of clumped Mytilus californianus (20, 35, 55 and 85 mm shell length), Pisaster ochraceus (arm length of 70‐110mm R) showed a preference for the medium sizes (35 and 55mm length). Prey‐size preference was positively correlated with predator size. Mean prey‐digestion times (insertion of the stomach, opening of the valves and digestive period) decreased significantly following fiiing of an artificial gape between the valves of mussels. When presented with different sizes of clumped filed mussels, starfish still chose medium mussels, indicating that stomach insertion, valve opening, and digestion rate may not be important constraints determining size selective predation. Measurements of the force required to dislodge mussels from the substratum and conspecifics showed an increasing exponential relationship with mussel size. Size selective feeding may be an energy maximizing and time minimizing strategy, where energy gained from choosing larger mussels is balanced against disproportionately increased costs in energy and time of removing large mussels from the substratum.
Seasonal Variation in the Biomass of Marine Macrophyta from Greek Coasts
Authors: Haritonidis S. , Nikolaidis G. , Tsekos I.
Published: May 2008

Abstract. The marine plant communities of the littoral zone in different biotopes of the Greek coasts were investigated in 1980‐81. Seasonal distribution and variation of marine plant biomass were assessed. The communities of Cystoseira crinita and C. compressa were outstanding with maximum biomass during the summer months. Corallina officinalis and Pterocladia capillacea + Viva rigida communities predominated with maximum biomass in autumn and exhibited a decrease in winter, except in stressed biotopes. The species diversity and productivity of seaweeds along the Greek coasts are interpreted in relation to a number of environmental parameters.
Picoplankton: Contribution to Phytoplankton Production in the Strait of Messina*
Authors: Magazzù Giuseppe , Bruni Vivia , Piccione Augusto , Platt Trevor , Irwin Brian , Rao D. V. Subba
Published: May 2008

Abstract. Biomass and primary production rates derived from photosynthesis‐light curves on picoplankton (< 1 um fraction) and total phytoplankton were compared for the Strait of Messina. Picoplankton biomass ranged between 0.063 and 0.094 mg Chi a m‐5 and accounted for 56–63 % of the total. Total primary production rates were between 0.22 and 1.56 mg C‐m‐2‐h‐1 of which the picoplankton contribution ranged from 24 to 43%. In this turbulent nearshore environment, the contribution of picoplankton to total phytoplankton production is considerably less than in calmer open‐ocean waters. Carbon assimilation numbers (Pmb), the initial slope (a), adaptation parameter (Ik), optimal irradiance (Im) and compensation intensity (Lm,) for the picoplankton were lower than for the > 1 μm fraction. Fitted respiration (RmB) for the picoplankton was, however, on the average higher (10.3 % of PmB) than for the > 1 μrn fraction (6.6 %). Assimilation numbers for the > 1 μm fraction in the southern stations were of higher magnitude (8.5–12.0 mg C mg Chi a‐1 h‐1) than in the northern station, possibly due to the impact of upwelled water flowing southward along the Sicilian coast.
Polychaete Vertical Zonation along a Littoral Cliff in the Western Méditerranean
Authors: ABBIATI M. , BIANCHI C.N. , CASTELLI A.
Published: May 2008

Abstract. Along the vertical cliff of Romito (Leghorn, Italy) 97 polychaete species were found from 0 to 6 m depth. Three depth related communities could be identified by trends in structural parameters (abundance, number of species, and diversity), by changes in species composition, and by the distribution of ecological and trophic groups. Such a zonation is consistent with the principal models proposed for the Méditerranean and seems mainly related to algal conditioning of the substrate.
Burrow Structure and Burrowing Activity of the Funnel‐feeding Enteropneust Balanoglossus aurantiacus in Bogue Sound, North Carolina, USA
Authors: Duncan P. Bruce
Published: May 2008

Abstract. This study of the enteropneust, Balanoglossus aurantiacus, in Bogue Sound, NC, provides information on the general structure and variability in geometry of its burrow, B. aurantiacus employs a funnel at the anterior end of its burrow to cave in surface sediments. It ingests, processes, then deposits these sediments back on the surface as fecal castings. Measurements made on resin casts of burrows and on photographs of surface features (burrow openings and funnels) revealed a new and consistent pattern of burrow construction. This pattern distinguishes B. aurantiacus burrows from those reported for other funnel feeders and enteropneusts (except, perhaps, forB. clavigerus). Laboratory and field observations revealed that, within its burrow, B. aurantiacus is elongated, can double‐back on itself, and can use anterior burrow openings for subsequent fecal castings. Tests for significant changes in location of surface features gave estimates of how frequently individuals in aquaria and field populations abandon old burrow locations and construct new burrows. Field observations showed that B. aurantiacus will reopen a blocked burrow opening.
Patterns of Activity of the Sea Urchin Paracentrotus lividus in the Bay of Port‐Cros (Var, France, Mediterranean)
Authors: Dance Catherine
Published: May 2008

Abstract. Tagged individuals of the sea urchin Paracentrotus lividus followed in Port Cros Island showed mostly nocturnal movements, with individual peaks of activity which were not coordinated for the population during the night period. The straight line distance travelled in 24 h has a mean value of 49 cm, with a range of 0 to 240 cm. Neither sea urchin size nor depth affect activity. The urchins living on rocky substrate moved significantly more than those on seagrass beds. From one day to another, the distance travelled by the population of urchins varies significantly; this is not related to season. The activity is negatively correlated with the mean wind speed; during a period of turbulence lasting several hours, movement was significantly oriented to the deep. Periods of inactivity of 1 or 2 days were observed; they are not coordinated for the individuals followed, and the relation between feeding and movement is not clear. Urchins seem to stay in a quite small area, at least for some months.
Organic Matter Derived from a Seagrass Meadow: Origin, Properties, and Quality of Particles
Authors: Velimirov Branko
Published: May 2008

Abstract. An investigation of the properties of particles found in wrack beds and suspended in the water body of a Posidonia oceanica system led to the following conclusion: except for the period of the leaf fall and at times of strong water movement (e. g. winter storms), the majority of the particles in the water show no similarity with seagrass particles. This is based on the comparison of C: N ratios and SEM inspection. Information on the magnitude of DOC fluxes in this system led to the formulation of the phase shift hypothesis from DOM to POM. Because wrack particles were shown to have relatively fast settling rates, it is expected that processes like adsorption onto inorganic particles, micellation and aggregate formation have more importance in regulating particle density in the water body than the resuspension of directly fractionated Posidonia debris. The implication of these findings are discussed and the importance of the Mediterranean seagrass P. oceanica as an energy source supporting secondary production in adjacent ecosystems is questioned.
The Effect of Salinity and Temperature Gradients on the Distribution of Littoral Microalgae in Experimental Solar Ponds, Dead Sea Area, Israel
Authors: Dor Inka , Ehruch Aline
Published: May 2008

Abstract. Several species of cyanobacteria, diatoms and one euglenid alga populated the littoral zone of hypersaline solar ponds investigated over a period of three years. The composition of the microalgae community changed with salinity and temperature. In the shallow marginal zone the diatoms predominated in winter and spring, at salinities of 30–72 g‐1‐1 and at temperatures not exceeding 30o°C, whereas in summer, cyanobacteria were the most abundant. In the deeper zone, at higher salinities and temperatures, cyanobacteria predominated throughout the year. The depth limit of algal growth was 60‐80cm, where salinity and temperature exceeded 211 g‐1‐1 and 48°C.

The most euryhaline and eurythermal among cyanobacteria were Aphanolhece halophytica Fremy and Phormidium hypolimneticum Campbell, among diatoms Nitzschia sp. aff. N. rostellata Hustedt, Amphora coffeaeformis (Agardh) Kutzing, and Navicula massadaea Ehrlich.
Intertidal Invertebrate and Algal Communities on the Rocky Shores of the Bay of Morbihan, Kerguelen (South Indian Ocean)
Authors: Lawrence John M. , McClintock James B.
Published: May 2008

Abstract.Both the emergent surfaces and tide pools of the rocky intertidal shores of the Bay of Morbihan, Kerguelen are depauperate in number of macroinvertebrate and macroalgal species. Diversity (H') was high and similar for macroinvertebrates in tide pools from the high to low intertidal and on the emergent surface exposed at extreme low‐tide when calculated in terms of numbers of individuals. H' was lower when calculated in terms of energy and twice as high for the tide pool in the high intertidal than the lower tide‐pools and the emergent surface. H' for macroalgae was 0 in the highest tide‐pool and highest in the lower tide‐pools. The density/species‐rank curves for the macroinvertebrates and the macroalgae are logarithmic but vary in linearity. Algal biomass was 37 % of the macroinvertebrate biomass on the emergent surface at the extreme low‐tide, but 106% in the highest tide‐pool. Twenty‐three months after denudation of the tide pools, the ratios of total densities of the macroinvertebrates (ind m‐2) to the original densities were 48 % for the pool in the high intertidal, 25 % for the middle tide‐pool, and 4 % for the pool in the low intertidal. The diversity indexes for the macroinvertebrates were similar to the original ones. Recolonization at Kerguelen is slow and shows an intertidal gradient. The composition of the rocky intertidal community at Kerguelen results from the rigorous physical environment and the small number and functional types of species. In the absence of major predators on macroinvertebrates and of herbivores on macroalgae, interaction among the species present seems to be competitive in nature.
The Influence of Metoclopramide and Melatonin on Activity and Schooling Behaviour in Chromis viridis (CUVIER, 1830; Pomacentridae, Teleostei)
Authors: Sparwasser Klaus
Published: May 2008

Abstract. The role of prolactin (PRL) in the neuroendocrine control of schooling behaviour and activity in the demoiselle Chromis viridis is analysed by administration of a prolactin‐releasing drug, metoclopramide (Paspertin®). In addition, the dependence of the activity state, schooling time, and colour changes on the administration of an epiphysial hormone, melatonin, is examined. Each substance tested affects schooling behaviour and activity by a different mechanism.
The Biology of Upogebia pusilla (PETAGNA) (Decapoda, Thalassinidea)
Authors: Dworschak Peter C.
Published: May 2008

Abstract. The distribution of the thalassinidean shrimp Upogebia pusilla was studied at four sites in the North Adriatic Sea: 1) a tidal flat in the lagoon of Grado, 2) a tidal flat at Lido di Staranzano near the mouth of the Isonzo, 3) a mud flat seawards of a salt marsh in a protected bay north of Rovinj, and 4) a sublittoral station in 6m depth near Aurisina. Information on grain size distribution, organic content, amount of debris, redox profiles and pH of sediment as well as temperature and salinity is given. Density, as determined by hole counts and a hole: burrow relationship derived from resin casting, generally increased with increasing water depth in the intertidal. The upper limits ranged between +10cm (Rovinj) and ‐20cm (Grado); densities between mean water and low water level varied strongly due to microtopography and macrophyte cover. Maximum densities in the intertidal ranged from 189 (Grado) to 2420 (Rovinj, juveniles) animals m2. Shrimp density at the sublittoral station ranged between 80 and 230 m“2. The zonation of the Upogebiidae and Callianassidae with respect to environmental parameters is discussed.
Marine Mangrove Fungi
Authors: Hyde K. D. , Jones E. B. G.
Published: May 2008

Abstract.Driftwood, prop roots and other mangrove samples were collected from the intertidal regions of Brillant and Anse Boileau mangrove stands, in the Seychelles. This material was examined for the presence of higher marine fungi. Forty seven species of marine fungi were collected (37Ascomycotina, 1Basidiomycotina, 9 Deuteromycotina), withHalocypluna villosuthe most common fungus, whileAniptodera mungrovii, Antennospora quudricorruita, Halosarpheia marina, Ascomyccte sp. (4), andLulworthiu grandisporawere collected frequently. The mycota of the two mangrove stands arc compared. A list of fungi recorded from mangroves is compiled.
Growth and Production of the Ark Shell Scapharca inaequlvalvis (BRUGUIÈRE) in a Lagoon of the Po River Delta
Authors: Mistri Michele , Rossi Remigio , Ceccherelli Victor Ugo
Published: May 2008

Abstract. Scapharcu inuequivalvis is an Indopacific bivalve which has recently immigrated to the Adriatic Sea and has progressively replaced dominant species within some infauna communities. Density, growth, and secondary production of this Arcidae were investigated between 1984 and 1985 in a bed located in a brackish environment of the Northern Adriatic coast.
The Biology of Upogebia pusilla (PETAGNA) (Decapoda, Thalassinidea)
Authors: Dworschak Peter C.
Published: May 2008

Abstract. Populations of the thalassinidean shrimp Upogebia pusilla were studied on tidal flats in the Northern Adriatic Sea. Biometric analysis showed a sexual dimorphism, especially in propodus size. Size frequency distributions revealed the presence of large animals during all seasons; recruitment by juveniles occurred in autumn. Moult intervals and moult increments were determined in the laboratory and used to generate growth curves which were compared with those calculated from size frequency distributions. The life span of U, pusilla is over 5 years. Ovigerous females occurred between March and September. Egg numbers were high in spring, lower in summer and increased with body size. The incubation time of embryos was 35 days; a female produces an estimated number of three egg batches during the breeding season. A total annual production of 994 kJ was estimated for a theoretical population of 100 animals; 13.5 % is spent for somatic growth, 31 % for egg production of females, and 55.2% is lost as exuviae. The population structures, growth and breeding patterns, as well as embryonic and larval development within the Upogebiidae and Callianassidae are discussed.
Metamorphose des Larves d'Echinides en Pleine Eau Metamorphosis of Echinoid Larvae in Midwater
Authors: Fenaux Lucienne , Pedrotti Maria Luiza
Published: May 2008

Abstract. Postlarvae and competent larvae of five species of echinoids (Genoadaris metadata, Arbticia lixula, Puracentrolus lividus, Echinocyamus pusillus, and Ediinocardiurn cordulum) were found in vertical hauls taken in the upper layer of the water column (30‐0 m). Competence of larvae was associated with both the extrusion of the adult rudiment and the retraction of the epidermis of the arms. Postlarvae of A. lixida were found offshore in areas where the sea floor is at a depth of more than 2(K)C.m. The occurrence of postlarvae far from their settlement grounds questions the necessity of a suitable benthic substrate to induce metamorphosis. Hypotheses dealing with the possibility of undergoing metamorphosis in midwater are discussed.

Des larves compétentes et des post‐larves de trois échinides réguliers: Arbacia lixula, Genocidaris maculata, Paracentrotus lividus et du clypéastréide Echinocyamus pusillus ont été trouvées dans des pêches verticales effectueés dans des couchesd'eaux superficielles (30‐0 m). Les larves compétentes montrent les caractéristiques consideréés comme des phénomènes irréversibles de la métamorphose: évagination du rediment et rétraction de 'épiderme des bras larvaires. Des post‐larves de 'oursin A. lixula ont été récoltées dans des pêches pratiquées loin de la côte au‐dessus de fonds de plus de 2000m. La présence de ces post‐larves loin des sites de recrutement des juvéniles pose le problème de la necessité du choix d'un substrat benthique pour que les évènements qui caractérisent la métamorphose puissent être induits. Ce problème et les hypothèses sur la possibilité d'une induction en pleine eau est discuté.
Contribution of the Bacterial and Microphytobenthic Microflora in the Energetic Demand of the Meiobenthos in an Intertidal Muddy Sediment (Kerguelen Archipelago)
Authors: Bouvy Marc
Published: May 2008

Abstract. An intertidal mud sediment in the Kerguelen Archipelago was sampled weekly from January 1982 to March 1983. Measurements were taken for organic matter (carbon and nitrogen) and biological (bacteria, microphytobenthos, and mciofauna) parameters. The sediment is rich in organic matter, with a mean organic carbon content of 130gC‐ m‐2. Benthic living components yield low mean biomasscs in relation to the total organic pool. Besides some marine inputs, the main allochthonous source was identified as terrestrial inputs. Benthic activities seemed strongly governed by food availability and not by temperature. Obvious seasonal changes in bacterial abundances (direct counts), primary production, and mciofauna distributions were observed. Photosynthctic production reached high values (up to 2275 mg C‐m‐2‐d‐1), reflecting the presence of a dense microphytobenthos. Preliminary energy budgets for two seasons (spring and winter) have been constructed. In both periods, the measured primary production can support the high mciofauna production.
Habitat Selection and Space Partitioning among two Mediterranean Blenniid Species
Authors: Koppel Veronika H.
Published: May 2008

Abstract. The utilization of the spatial resources of two syntopic blenniid species ‐ Blennius cunevue and Blennius incognitas ‐ has been investigated in silu and under laboratory conditions. Both species occupy bore holes of the mussel Lithophugu in the sublittoral zone. B. cunevue dominates the more shallow zone (x̄= 0.68 m) and prefers smaller (x̄= 12.76 mm diameter) and horizontal bore holes. B. incognitus inhabits the same depth range as B. cunevue but occupies larger bore holes (x̄= 14.57 mm) in a deeper zone (x̄= 0.86 m). Individuals of B. incognitus do not prefer a special inclination angle. The two blenniid species defend territories with different intraspecific sizes: the mean territory radius of B. cunevue is 6.87 mm, of B. incognitusx̄= 10.95. Mechanisms to reduce competition include different activity rhythm, interspecific social dominance, and differences in territoriality. B. cunevue is the dominant species; its territories arc defended against conspecifics and against B. incognitus.
The Influence of Primary Production Rate on the Population Dynamics of Patella granulans, an Intertidal Limpet
Authors: Bosnian A. L. , Hockey P. A. R.
Published: May 2008

Abstract. The production rates of intertidal algae at seven study sites in the Saklanha Bay area. South Africa, were measured monthly for 15 months. Algae grew rapidly and formed extensive, permanent mats on shores that were enriched with nutrients from the dissolved guano of seabirds. The most significant correlate of limpet (Patella granulans) growth was the rate of algal production; more rapid limpet growth on nutrient‐rich shores, combined with the effects of predation by African Black Oystercatchers Haematopus moquini on limpets, led to differences in the size structures and life‐history patterns of populations of limpets on enriched and unenricheci shores. The rate of primary production affected relationships between intertidal organisms at all trophic levels and influenced patterns of organization within the community.
The Effects of Zn, Mn, and Co Accumulation on Growth and Chemical Composition of Fucus vesiculosus L under Different Temperature and Salinity Conditions
Authors: MUNDA IVKA M. , HUDNIK V.
Published: May 2008

Abstract. Combined effects of temperature, salinity, and metal enrichment (Zn, Mn, Co) on the growth rate and chemical composition of Fucus vesiculosus L. were studied in culture. Factorial combinations of two temperatures and three salinities were used. The results indicated that the accumulation of Zn and Mn into algal tissue was enhanced by dilution of the media, whereas Co accumulation exhibited maxima at the medium salinity. Zn accumulation was enhanced by temperature, while the opposite was true for Mn and Co.

In the presence of metals the usual dilution‐induced changes in growth activity and chemical composition of Fucus plants were altered, while responses to the temperature factor remained unchanged. In diluted media, growth activity and mannitol content decreased along with a simultaneous increase of protein content. In the presence of Zn and Mn the mannitol content exhibited peaks at the medium salinity; in the presence of Co the dilution‐induced pattern remained unchanged. Salinity‐induced changes in growth and protein content were altered in the presence of metals. Maxima in growth rates were found at the medium salinity. Growth was higher in extremely diluted media than in scawater, indicating an inversion of responses to the salinity factor. Both the growth rate and mannitol content were lowest under the influence of Zn.
A Map of the Posidonia oceanica Beds of Marina ?Elbu (Corsica, Mediterranean)
Authors: Meinesz Alexandre , Boudouresque CharlesF. , Lefevre Jean‐robert
Published: May 2008

Abstract. A large‐scale map of the Posidonia oceanica seagrass beds as well as other benthic substrata and communities was compiled for a cove of a marine reserve free from pollution and man‐made disturbance. An extensive diving survey of the cove and the interpretation of aerial colour photographs were used. The greater part of the cove is occupied by the P. oceanica meadow. Patches of dead “matte” were observed at a depth of between 7 and 14 m. They may be the result of a natural hydrodynamic equilibrium between building and erosion.
Reasons for Spatial Microdistributions of Foraminifers in an Intertidal Pool (Northern Adriatic Sea)
Authors: Hohenegger Johann , Piller Werner , Baal Christian
Published: May 2008

Abstract. The spatial microdistribution of foraminifers was tested by the method of quadratic samplings on 2 sample grids in an intertidal pool of the northernmost Adriatic sea. Abundant species of foraminifers exhibit patchy distributions throughout; the distribution‐patterns of some species correspond nearly completely. Using statistical methods (regression‐ and correlation‐analyses) correlations to abiotic and biotic factors (water depth, exposure rate, seagrass, benthonic algae) were ascertained. The significant correlations of the foraminiferal frequencies to blue‐green algae and/or diatoms enable an interpretation of these connexions as food dependences. Several foraminiferal species seem to have specific diets.
Biogeography, Substrate Preference, and Feeding Types of North Adriatic Intertidal Collembola
Authors: Christian Erhard
Published: May 2008

Abstract. A survey of North Adriatic intertidal Collembola is given, including the first records of Friesea acuminata, Archisotoma interstitialis, Entomobrya dollfusi, and Pseudosinella hauseri. Granulometric and biococnological analyses of culittoral loose sediments allowed determination of the animals' substrate preference. The limitation to cuhaline habitats is tested by comparison with mixohaline shores nearby. Life‐form typology is applied to elucidate the largely unknown relations of intertidal Collembola to the sediment surface or superficial strata. The different modes of nutrition are distinguished by mouthparts and by gut content analyses.
Book Reviews
Authors: Nebelsick Monika
Published: May 2008

Book reviewed in this article:

Westheide, W. & C. O. Hermans (Eds.): The Ultrastructure of Polychaeta. Microfauna Marina, Vol. 4. Ed.: P. Ax, Veröffentl. der Akademie der Wissenschaften u. der Literatur, Mainz. Gustav Fischer Verlag, Stuttgart, New York, 1988. 494 pp., numerous figs. Hard cover; DM 118,—.
Seasonal Changes in Soluble Carbohydrates, Starch, and Energy Content in Mediterranean Seagrasses
Authors: Pirc Helmut
Published: May 2008

Abstract. In all scagrass species investigated, rhizomes were the main storage organs for soluble carbohydrate reserves, and the highest levels were found in Cymodocea nodosa (Ucria) Ascherson. Sucrose was the primary soluble carbohydrate identified in Posidonia oceanica (L.) Delile, and Zostera noltii Hornem. This disaccharide was dominant in Cymodocea nodosa roots, as well as in its rhizome in winter. Myo‐inositol was the main cyclitol in Zostera noltii. In Cymodocea nodosa leaves 1‐chiro‐inositol was the main sugar component; it was also present to a lesser extent in the roots and rhizomes. The amounts of glucose and fructose were correlated with growth to a certain extent in all species. Higher amounts of starch were stored in the rhizomes of Posidonia oceanica and Zostera noltii. The energy content of Mediterranean scagrasses was significantly higher than in tropical species. No distinct seasonal trend in energy content could be observed.
Regional Commercial Sponge Extinctions in the West Indies: Are Recent Climatic Changes Responsible?
Authors: Vicente Vance P.
Published: May 2008

Abstract. Long‐term changes in the distributional patterns of commercial sponges (Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater (e. g., Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles (e. g., Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera (Spongia and Hippospongia) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned.
Circannual Cycle and Oxygen Consumption in Eudendrium glomeratum (Cnidaria, Anthomedusae): Studies on a Shallow Water Population
Authors: Arillo A. , Bavestrello G. , Boero F.
Published: May 2008

Abstract. The oxygen consumption of Eudendrium glomeratum was measured monthly, throughout the period of active presence of the species in the field, to obtain indications on its physiological condition in the different phases of the cycle. Sets of one hundred polyps were assayed in the laboratory under normothermic (according to field temperature: 14–19°C) and hyperthermic conditions (22–25°C). The different response to identical temperatures at the extremes of the cycle, together with a differential ability to face stressful conditions in the same periods, suggests that other factors, besides temperature, regulate the seasonal cycle of Eudendrium glomeratum.
Ecology of Nematodes in the Mediterranean Seagrass Posidonia oceanica (L.) Delile 1. General Part and Faunistics of the Nematode Community
Authors: Novak Rudolf
Published: May 2008

Abstract. The nematode fauna of the phytal region of a stand of the Mediterranean seagrass Posidonia oceanica (L.) Delile was studied in a shallow subtidal location (5 m) at the island of Ischia (Gulf of Naples, Italy). During a one year's growth‐cycle of the seagrass, abundance and faunal composition of the nematode community were investigated in a stratified sampling survey. Ninety seven species of nematodes were found.

Nematode density and biomass ranged from 1.3 · 105 indiv. · m‐2 (0.02g dwt · m‐2) in winter to 5.5 · 105 indiv. · m‐2 (0.08 g dwt · m‐2) in early autumn. Density and biomass of nematodes were much lower and showed more marked seasonal fluctuations in the leaf strata than in the stem stratum of the seagrass.

Diversity and seasonal homogeneity (expressed with Riedl's index) were much lower in the two leaf strata (25–36 species, 29.6 ho%) than in the stem stratum (60–70 species, 42.5 ho%).

The nematode community of the leaf stratum can be characterized as a Chromadora nudicapitata – Monhystrella sp. –Symplocostoma tenuicolle– community and is clearly set off from the stem stratum community (9.2% Riedl's ho%), which is characterized as a Molgolaimus sp. 1 –Epsilonema sp. 1 –Chromadora nudicapitata– community.

In the seasonal succession, the leaf stratum fauna shifts from a chromadorid‐dominated community (from winter to summer) to a monhysterid‐dominated community in early autumn. The stem stratum fauna shifts from a epsilonematid‐dominated fauna in winter to a molgolaimid‐dominated fauna in summer and early autumn.

The distribution of nematode size classes showed a clear selection toward small animals (< 1 mm lenght), although marked seasonal fluctuations in size class distribution were observed. A modified approach for describing the trophic structure of the nematode fauna is presented.

The observed abundance patterns and changes of community composition are discussed in relation to the development of habitat complexity and in relation to trophic conditions in the scagrass stand according to the seasonal growth rhythm of the plants and their aufwuchs‐community.
Cyclic Changes along Posidonia oceanica Rhizomes (Lepidochronology): Present State and Perspectives
Authors: Pergent Gérard , Boudouresque Charles‐François , Crouzet Alain , Meinesz Alexandre
Published: May 2008

Abstract. Leaf sheaths in the seagrass Posidonia oceanica can persist for millcnia and they show, according to their insertion rank, cyclic variations in parameters such as thickness and tissue structure. The principal cycles are always annual, but pluriannual cycles can also be detected. Annual cycles may be changed by environmental parameters such as light, temperature, or water movement. In a fashion analogous to the study of annual tree rings (dendrochronology), the study of cyclic changes in Posidonia oceanica sheaths is thus a technique allowing the study of past yearly changes in the near‐shore environment.
Shallow‐Water Gasohydrothermal Vents of Ushishir Volcano and the Ecosystem of Kraternaya Bight (The Kurile Islands)
Authors: Tarasov V. G. , Propp M. V. , Propp L. N. , Zhirmunsky A. V. , Namsakakv B. B. , Gorlenko V. M. , Starynin D. A.
Published: May 2008

Abstract. A marine ecosystem in the crater of the Ushishir Volcano (Kraternaya Bight, Yankich Island, the Kuriles) showing gasothcrmal activity was studied for hydrographical, hydrochemical, and biological characteristics. Maximal changes in chemical and biological characteristics were observed in the surface water layer of 0–5 m. This layer had higher water temperature, was saturated with volcanogcnic carbon dioxide (up to 2000 10‐6 torr), ovcrsaturatcd with oxygen (up to 200 %), and contained high concentrations of chlorophyll a. Hydrogen sulfide was found in the surface water layer and at a depth of 15 m in the area of maximal effect of volcanic effluents.

The planktonic community is characterized by high rates of production and destruction of organic matter only in the 0–5 m layer. Daily vertical migrations of the ciliatc Mesodinium rubrum were observed, which caused “red tides”.

Bacterial, algobacterial, and diatom mats developed on the bottom of the bight in the zone of gasohydrothermal vents and in areas of volcanic water seeping. The rate of organic matter production in algobacterial mats reached 33.4g C‐rrr2‐d‐l, chcmolithotrophy predominating. Bottom settlements had high population density and great animal biomass, which reached 10 kg m‐2 in gasohydrothermal fields. They obtain sufficient energy from primary production of microphy‐tobenthos, algobacterial, and bacterial mats. Bcnthic species dominant in the bight were not found off the Ushishir Islands.

Some species of macrobenthos inhabiting the Kraternaya Bight differ markedly in size and biomass from the same species found beyond the bight.
Artificial Reefs in the Low Productive Marine Environments of the Southeastern Mediterranean
Authors: Spanier E. , Tom M. , Pisanty S. , Almog‐Shtayer G.
Published: May 2008

Abstract. Fishery yields in the oligotrophic waters of the Southeastern Mediterranean arc low due to habitat and food limitations. A four year study of a complex of artificial structures established in the coastal waters of Israel points to several possible solutions to these problems. One approach is the artificial enrichment of the man‐made reef with trash fish. This, together with the configuration of the reef, caused a significant increase in the abundance of fish predators such as groupers of the genus Epinephclus. Omnivores and herbivores were attracted only by the presence of artificial structures. Some species, such as the slipper lobster Scyllurides lulus, only use the man‐made reef for shelter during part of the day or season; they forage over a much larger area the rest of the time and are important “importers” of food to the artificial habitat. Artificial kelp were effective in recruiting juveniles and small fishes to the site.
Temporal Variations of Benthic Bacterial Microflora on the Northwestern Mediterranean Continental Shelf and Slope
Authors: Delille Daniel , Guidi Laurence D. , Cahet Guy
Published: May 2008

Abstract. Bacterial (direct and heterotrophic counts, heterotrophic potentials) and organic matter (org C, org N) parameters were studied over 2 years in the surface sediments of 3 stations located on the continental shelf (station A: 15m; station B: 35m) and slope (station C: 910m) in the northwestern Mediterranean Basin.

Although logistic constraints did not allow a satisfactory sampling periodicity in the offshore survey, some seasonal trends were still observable at the deepest station. Variations were quantitatively more important in the two shallow sediments (from 3×102 heterotrophic bacteria – ml‐1 in December 1984 to 107 heterotrophic bacteria‐ml‐1 in March 1986). Epifluorcsccncc direct counts were relatively constant (5×108 cells‐ml‐1), while heterotrophic potentials (with 14C labelled glucose and glutamic acid) showed a succession of very short pulses over the year. Different concentrations of organic matter (from 0.2% orgC at 15m to 0.8% orgC at 35m) appeared to sustain very similar bacterial numbers. Nevertheless, a certain relation between the seasonal evolution of bacterial and organic matter parameters was discernable. Although depth apparently had no measurable effect on maximal spring bacterial densities, it seemed to lessen the summer and winter decreases in the two shallow stations.
Summer Phytoplankton Physiognomy in Coastal Waters of the Gulf of Naples
Authors: Zingone Adriana , Montresor Marina , Marino Donato
Published: May 2008

Abstract. Thirteen sampling cruises were conducted at weekly intervals in the inner part of the Gulf of Naples in the summer of 1983 to investigate the effects of excess nutrient inputs on phytoplankton communities. High surface phytoplankton concentrations (up to 1.15 ×108 cells 1‐1) were recorded, particularly near Naples harbour and along the eastern coast, two locations that receive most of the area's sewage and industrial discharge. Phytoplankton populations were generally dominated by small species, mainly diatoms, which were associated with small phytoflagcllatcs. Species diversity values were relatively high (H′≤ 3.62) in most samples. Throughout the sampling period a high spatial and temporal variability for phytoplankton abundances and species composition was observed.