Neritic Waters Research Articles

Exploitation of distant Antarctic waters and close neritic waters by short‐tailed shearwaters breeding in South Australia

AbstractIdentifying the primary foraging grounds of abundant top predators is of importance in marine management to identify areas of high biological significance, and to assess the extent of competition with fisheries. We studied the search effort and habitat selection of the highly abundant short‐tailed shearwater Puffinus tenuirostris to assess the search strategies employed by this wide‐ranging seabird. During the chick‐rearing period 52 individuals were tracked performing 39 short foraging trips (1–2 days), and 13 long trips (11–32 days). First‐passage time analysis revealed that 46% of birds performing short trips employed area‐restricted searches, concentrating search effort at an average scale of 14 ± 5 km. Foraging searches were more continuous for the other 54%, who travelled faster to cover greater distances, with little evidence of area‐restricted searches. The prey returned indicated that continuous searchers consumed similar prey mass, but greater prey diversity than area‐restricted search birds. On long trips 23% of birds travelled 500–1000 km to neritic (continental shelf) habitats, showing weak evidence of preference for areas of higher chlorophyll a concentration, and foraged at a similar spatial scale to short trips. The other 76% performed rapid outbound flights of 1000–3600 km across oceanic habitats commuting to regions with higher chlorophyll a. The spatial scale of search effort in oceanic habitat varied widely with some performing broad‐scale searches (260–560 km) followed by finer‐scale nested searches (16–170 km). This study demonstrates that a range of search strategies are employed when exploiting prey across ocean basins. The trade‐offs between different search strategies are discussed to identify the value of these contrasting behaviours to wide‐ranging seabirds.

Efforts to reduce sea turtle bycatch in the shrimp fishery in Northeastern Brazil through a co-management process

The neritic waters of the state of Sergipe in Northeastern Brazil is adjacent to the main nesting area of the olive ridley sea turtles ( Lepidochelys olivacea) in the Western Atlantic Ocean and an important area for shrimp trawl fishery. To address the problem of incidental mortality of sea turtles captured during trawling and reduce the risk of overexploitation of shrimp stocks, Projeto TAMAR/ICMBio, a Brazilian sea turtle conservation program, has adopted two main strategies: (1) the implementation of a marine monitoring program and (2) active participation in local forums. This paper describes the conflicts among stakeholders, the arrangements and established mechanisms of negotiation aimed to protect sea turtles and shrimp grounds, and strategies to reduce conflicts between user groups. The analysis of this co-management process highlights the importance of stakeholder participation in resource management decision-making through a cooperative process, the role assumed by non-governmental organizations as mediators, and the factors that influence this system. The key factors and actions learnt from the current study include clear identification of the conflicts, identification of stakeholders – both local and external, and local leaders, encouragement of actors and leaders to participate, support and strengthening of local groups, legitimization of the discussion forums through involvement with government, formalization of decisions taken through legislation, and monitoring of the management efficacy.

A new species of Centropages (Copepoda: Calanoida) from the neritic waters of Sharm El-Sheikh, the Red Sea

A new species of calanoid copepod, Centropages uedai sp. nov., is described from the neritic waters of the northern Red Sea. This species is characterized by: (1) symmetry of a globular female genital double-somite that is ornamented with an anterior irregular group of spinules as well as transverse and dorsolateral rows of spinules on each side; (2) second exopodal segment of female leg 5 bearing a strong trough medial process serrated along the distal 4/5 of its posterior margin; (3) second exopodal segment of male right leg 5 serrated laterally along distal 1/5 of its medial process; (4) third exopodal segment of male right leg 5 with medial seta bifurcated at its tip and with hyaline ridge on both sides; and (5) second exopodal segment of male right leg 4 asymmetrical with undulating, thicker and longer lateral spine than left leg. The new species does not belong to any known species groups of the genus.

Diet and trophic position of the devil rays Mobula thurstoni and Mobula japanica as inferred from stable isotope analysis

This study confirms the diet and determines the trophic position of the bentfin devil ray (Mobula thurstoni) and spinetail devil ray (Mobula japanica) in the south-west Gulf of California. There has been an active fishery in the area for these filter-feeding elasmobranchs, which are highly susceptible to exploitation due to low fecundity and long lifespan. However, information on their basic biology is scarce. δ13C and δ15N values of devil rays and zooplankton (sorted according to trophic level: herbivores, carnivores and omnivores) were determined over a period of 11 months, to allow for isotopic temporal variations in isotopic signals at the base of the food web. On the basis of fractionation factors we determined that bentfin and spinetail devil rays fed mainly on Nyctiphanes simplex, the most abundant euphausiid in neritic waters of the Gulf of California. The trophic positions obtained for the devil rays correspond to second level consumers.

Influence of hydrographic features on larval fish distribution during the south‐westerly monsoon in the waters of Taiwan, western North Pacific Ocean

The spatial distribution patterns of fish larvae and the relationships with hydrographic conditions in the waters surrounding Taiwan were studied in August 2004 when the south-westerly monsoon prevailed. A total of 6566 fish larvae were identified, belonging to 80 families, 129 genera and 230 species. Cluster analysis revealed two station groups, one associated with the South China Sea Surface Current (SCSSC) and the other with the Kuroshio Current (KC). The SCSSC group was characterized by mostly coastal and neritic species, and the KC group was predominated by oceanic species. Larger fish larvae were generally more abundant in the neritic waters west of Taiwan where the SCSSC prevails than in the waters east of Taiwan where the KC prevails. The combination of chlorophyll a, zooplankton and nitrite best explained the relationship of larval fish distribution and environmental variables, implying that the distribution of fish larvae in summer was closely linked to the food source. The changing of monsoons potentially affects the succession of water masses and the transport and assemblage of fish larvae in this study area.

Impacts of variability of habitat factors on species composition of ichthyoplankton and distribution of fish spawning ground in the Changjiang River estuary and its adjacent waters

During June, August and October 2006, there were three multi-disciplinary surveys carried out in the Changjiang River estuary and its adjacent waters (122°00′–125°00′E, 27°50′–34°00′N) by R/V Beidou to study the species composition and abundance of ichthyoplankton (including fish eggs, larvae and juveniles), the spatial distribution of fish spawning ground and their relationship with habitat factors. There were 29, 29 and 25 grid stations sampled in the three cruises, respectively. The ichthyoplankton samples were collected by horizontally towing with a macro-plankton net (mouth diameter 80 cm, length 270 cm, mesh size 0.50 mm) at the sea surface, and the towing speed was 3.0 n mile/h at each sampling station. The towing lasted for 10 min. After hauling for each station, habitat factors including temperature and salinity were measured by Sea Bird-25 CTD. Samples were preserved in 5% formaldehyde solution immediately after sampling for analysis in laboratory. Since the trawl speed could not be accurately evaluated due to the effects of ocean currents and wind-induced wave, the amount of ichthyoplankton was evaluated by actual number of the sampling haul in each station. Ichthyoplankton collected were divided into three categories: dominant species, important species and main species by the index of relative importance ( IRI). There are 71 species (including 1200 fish eggs and 2575 fish larvae and juveniles) collected during 3 cruises and 59 species have been correctly identified to species level, which belongs to 50 genera, 37 families and 9 orders; while 5 species can only be identified to genera level, 1 species only identified to family level and 6 species identified to order level. These 59 species identified to species level and 5 species identified to genera level are divided into three ecological patterns, i.e., brackish water species, neritic water species and coastal water species. Warm water species have 34 species in those 59 species identified to species level, accounting for 57.63%, warm temperature species have 25 species, accounting for 42.37%. According to the analysis of IRI, the dominant species are Engraulis japonicus (in June and August, that is important species in October), Scomber japonicus (in August), and Johnius grypotus (in October) during the survey; important species are Cynoglossus joyneri (in June and August), Trichiurus lepturus (in June, August and October), Gonorhynchus abbreviatus (in August), Stolephorus commersonii (in October), Saurida undosquamis (in October) and Saurida elongate (in October), and main species have 12 species in June, 9 species in August and 10 species in October, respectively. The amount of fish eggs and larvae of the dominant species, important species and main species (28 species) are 97.50% and 97.13% of the total amount of fish eggs and larvae, respectively, which are the important composition of fish eggs and larvae in the Changjiang River estuary and its adjacent waters. In June and August of 2006, if compared with that in corresponding months in 1986, there are great changes in the habitat factors especially for temperature and salinity in the investigating areas: high salinity water from off-shelf is much closer to the coastal areas which results in the dramatic increase of sea surface salinity during all three surveys. Sea surface temperature, on the other hand, decreases distinctively in June, but significantly increases in August. The run-off of the Changjiang River greatly reduced due to the long-term drought in summer 2006, which is responsible for the great changes of habitat factors in the Changjiang River estuary and its adjacent waters. The habitat of the Changjiang River estuary is greatly changed, which consequently has significant influences on the spawning, breeding and the spatial distribution of spawning ground of neritic water species, such as Sardinella zunasi, Thryssa kammalensis, Thryssa mystax, Setipinna taty and S. commersonii ect, and coastal water species, such as Ilisha elongate and Konosirus punctatus ect.

Erratum to: Oceanic residents, neritic migrants: a possible mechanism underlying foraging dichotomy in adult female loggerhead turtles (Caretta caretta)

To reveal the mechanism underlying intrapopulation variation in the use of feeding habitats (oceanic vs. neritic) by adult female loggerhead turtles (Caretta caretta), we compared telomere length in the epidermis (a proxy for age) between oceanic- and neritic-foraging recruits (first-time nesters). Based on egg-yolk stable isotope ratios, recruits at Yakushima Island, Japan, were clearly divided into small oceanic planktivores and large neritic benthivores. There were no significant differences in telomere length between oceanic and neritic foragers, suggesting that they start reproduction at similar ages. Turtles that experienced faster growing conditions during their oceanic early lives may achieve sexual maturity there, while others may move from oceanic areas into neritic habitats, switching diets from nutrient-poor macroplankton to nutrient-rich benthic fauna in order to compensate for their earlier slow growth rate and continue their sexual development, reaching maturity in neritic waters.

Characteristics and flux of settling particulate matter in neritic waters: The southern Yellow Sea and the East China Sea

The typology and flux of settling particulate matter (SPM) were investigated based on sediment trap sampling at six typical stations in the Yellow Sea and the East China Sea. The settling particulate matter in the neritic seas was sorted into three categories, lithogenic particles, living organisms, and particle aggregates. The mass of individual organisms is an important portion of particulate matter in the neritic waters. The aggregates contain six types, mucus aggregates, fecal pellets, diatom aggregates, silicoflagellate aggregates, tintinnids, and miscellaneous aggregates, of which the silicoflagellate aggregates and tintinnids are the most abundant in the Yellow Sea and the East China Sea. High particle fluxes, such as 215 to 874 g m(-2). day(-1) SPM in the bottom layer, were found at three stations where the water was well mixed, and the maximum flux was detected in the boundary area between the Yellow Sea and the East China Sea, where a wide nepheloid layer was present. Hence, particle flux in neritic waters can be easily shifted by water turbulence. The net vertical flux (123 to 961 mg C day(-1)), the contribution of lateral advection to resuspension flux (5 to 76%), and the particulate organic carbon export ratio (18 to 60%) were estimated for the other three stations where the water was stratified. The highest values were all found in the upwelling area off the Zhejiang coast, suggesting that the area of high productivity provides a high net vertical flux of SPM. (C) 2010 Elsevier Ltd. All rights reserved.

Use of stable isotopes to quantify seasonal changes of trophic niche and levels of population and individual specialisation in seabirds

Niche variation is a widespread phenomenon that has important implications for ecolog- ical interactions and conservation biology, but few studies have quantified the trophic niche width (TNW) and its within- and between-individual components. We used stable isotopes of body feathers to investigate (1) seasonal isotopic niche changes of 4 southern procellariiforms and, (2) the level to which individuals are specialised relative to their population within each season. (1) δ 13 C and δ 15 N values of chicks and adults indicated a well-defined trophic segregation within the seabird assem- blage during both the breeding and poorly known moulting (inter-nesting) periods, and they under- lined marked species-specific seasonal changes. One species (light-mantled sooty albatross) remained within the Southern Ocean both during breeding and body feather moult, while the 3 others migrated either to oceanic subtropical waters (wandering and sooty albatrosses) or high isotopic marine areas (e.g. productive neritic waters; white-chinned petrel) during the moulting period. (2) Isotopic vari- ances and TNW were generally low, indicating that birds belong to isotopic specialist populations within a given period. Variances and TNW were larger for white-chinned petrel chicks and light-man- tled sooty albatross adults, respectively, indicating isotopic generalist populations and revealing 2 new foraging behaviours. Individual white-chinned petrel chicks segregated by their feather iso- topic signatures, thus indicating individual/pair specialisation of parent birds during the chick-rearing period. The light-mantled sooty albatross population included mostly isotopic generalist individuals during the moulting period, with individuals using different habitats and diets. The study highlights the utility of feather isotopic signature for determining TNW and points out the necessity to develop such new approaches to better depict niche variations at both population and individual levels.

Spatiotemporal habitat use by breeding sooty shearwaters Puffinus griseus

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 391:209-220 (2009) - DOI: https://doi.org/10.3354/meps07932 Spatiotemporal habitat use by breeding sooty shearwaters Puffinus griseus Scott A. Shaffer1,*, Henri Weimerskirch2, Darren Scott3, David Pinaud2, David R. Thompson4, Paul M. Sagar5, Henrik Moller3, Graeme A. Taylor6, David G. Foley7,8, Yann Tremblay1,9, Daniel P. Costa1 1Ecology and Evolutionary Biology and Institute of Marine Sciences, University of California, 100 Shaffer Road, Santa Cruz, California 95060-5730, USA 2Centre d’Etudes Biologiques de Chizé, CNRS, 79360 Villiers en Bois, France 3Department of Zoology, University of Otago, 340 Great King Street, Dunedin, New Zealand 4National Institute of Water and Atmospheric Research, 301 Evans Bay Parade, Wellington, New Zealand 5National Institute of Water and Atmospheric Research, 10 Kyle Street, Riccarton, Christchurch, New Zealand 6Department of Conservation, PO Box 108, Kilbirnie, Wellington, New Zealand 7Joint Institute for Marine and Atmospheric Research, University of Hawaii, 1000 Pope Road, Honolulu, Hawaii 96822, USA 8National Oceanic and Atmospheric Administration, Southwest Fisheries Science Center, 1352 Lighthouse Avenue, Pacific Grove, California 93950, USA 9Centre de Recherche Halieutique Méditerranéenne et Tropicale, IRD, 34203 Sète cedex, France *Email: shaffer@biology.ucsc.edu ABSTRACT: Breeding sooty shearwaters Puffinus griseus cycle between long (11 to 14 d) and short (1 to 2 d) foraging bouts at sea, but no information exists on bird behavior during these trips. We tested the hypothesis that shearwaters use these long trips to travel to distant Antarctic waters compared to remaining in local waters. Patterns of habitat use of 28 breeding sooty shearwaters were studied using 6 g archival data loggers that recorded location, environmental temperature, and diving behavior. Dive activity was compared to remotely-sensed environmental data to characterize the habitats visited by shearwaters on long and short trips. Sooty shearwaters traveled predominantly (70% of all long trips) to cold oceanic waters along the Polar Front (mean ± SD, 1970 ± 930 km from colony) on long trips or remained within warmer neritic waters of the New Zealand shelf (515 ± 248 km from colony) on short trips. Diving depths (mean depth 15.9 ± 10.8 m, max depth 69.9 m, n = 2007 dives) were not significantly different between excursion types. Activity patterns suggest that shearwaters commuted between distant foraging grounds (e.g. Polar Front) and the breeding colony and that more than 95% of diving activity occurred during daylight hours. Although shearwaters traveled primarily to Antarctic waters on long trips, occasional trips around New Zealand waters were observed; all but 2 birds were from the northern-most study colony. Oceanic habitats in Antarctic waters were substantially different from neritic habitats around New Zealand, indicating that shearwaters experience dramatically different environmental conditions associated with each excursion type. The ability of sooty shearwaters to use 2 vastly different habitats provides greater flexibility for maximizing resource acquisition during breeding and reduces competition near the colony. KEY WORDS: Activity · Archival data logger · Diving · Geolocation · Puffinus griseus · Tracking ·Sea surface temperature · Sooty shearwater Full text in pdf format PreviousNextCite this article as: Shaffer SA, Weimerskirch H, Scott D, Pinaud D and others (2009) Spatiotemporal habitat use by breeding sooty shearwaters Puffinus griseus. Mar Ecol Prog Ser 391:209-220. https://doi.org/10.3354/meps07932 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 391. Online publication date: September 28, 2009 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2009 Inter-Research.

Temporal and size-related variation in the diet, consumption rate, and daily ration of mackerel tuna (Euthynnus affinis) in neritic waters of eastern Australia

AbstractGriffiths, S. P., Kuhnert, P. M., Fry, G. F., and Manson, F. J. 2009. Temporal and size-related variation in the diet, consumption rate, and daily ration of mackerel tuna (Euthynnus affinis) in neritic waters of eastern Australia. – ICES Journal of Marine Science, 66: 720–733. The diet, food consumption, and ration of mackerel tuna (Euthynnus affinis) were studied in Australian neritic waters. Overall, 43 prey taxa were identified from 271 stomachs. The diet was primarily pelagic clupeoids (78% by wet weight, WW; 71% by frequency of occurrence, FO) and demersal fish (19% WW; 32% FO). Multivariate regression tree analysis revealed that temporal differences, followed by fish size, explained most of the variation in the diet composition. Autumn diets differed from those in other seasons because tuna ate virtually only engraulids then. During other seasons, engraulids were still the dominant taxon in the diet, but fish also consumed a greater variety of other prey. Small tuna seemed to target small pelagic crustaceans and teleosts, and medium and large tuna to consume larger pelagic and demersal teleosts. Prey consumption increased with tuna size from 26.42 to 108.03 g d−1 for small and large tuna, respectively. Conversely, daily ration decreased with increasing tuna size from 4.10 to 1.95% body weight per day for medium and large tuna, respectively. Mackerel tuna consumed an estimated 25 036 t year−1 in the study region (170 990 km2). Diet studies are becoming increasingly important in informing ecosystem models, and this study confirmed the need for sampling regimes to capture temporal and size-related variation in diet composition, to maximize the utility of data for use in such models.

Temporal Variation of Early Larval Stages of the Long-Spined Sea UrchinDiadema antillarumin La Parguera, Puerto Rico

This study describes temporal variations of early larval stages of the long-spined sea urchin, Diadema antillarum in neritic waters of La Parguera, Puerto Rico. Larvae were sampled with oblique plankton tows between the new and full moons at monthly interval from April 2005 to July 2006, and September 2006. Early pluteus stages (< 5 days old) were found in 13 out of the 16 months of sampling, indicating that Diadema spawns throughout the year. Mean abundances were significantly higher during April and July 2005 compared to the other months, suggesting higher reproductive activity during these months. Larval abundances were variable between years and successive months possibly reflecting a patchy distribution of larvae. Drogues released during the April spawning season from an area of high aggregations of mature adults indicated that a neritic, topographically steered flow fringing the inner shelf forereef platforms confined the early larval stages of Diadema within the insular shelf of La Parguera.

Macrobenthic biodiversity and sea floor landscape structure

Ascertaining the patterns and determinants of soft-sediment biodiversity is critical to our overall understanding of coastal and marine processes. Studies of diversity in the deep sea and neritic waters have largely focused on levels of species diversity, differences in these levels along depth and geographic gradients, and how environmental characteristics within and among different geographic areas may drive the differences and patterns found. Among the environmental characteristics examined, habitat structure and heterogeneity have been identified as potentially playing a key role they play in shaping biodiversity patterns. Although habitat-related factors such as sediment characteristics have always been considered, it has been in the absence of any quantified benthic landscape framework. A benthic landscape, or benthoscape, is comprised of a set of patches that are repeated over a kilometers -wide area. Such patches have within-patch structure and in soft-sediments are often defined by their geophysical characteristics, although distinct biotic patches also can comprise a benthoscape. Benthoscapes contain the habitats that generate and support soft-sediment species diversity, and these habitats indeed are a component of overall biodiversity. Although, the study of benthoscape structure and dynamics is only now emerging, marrying this with research on biodiversity patterns will move our understanding of both forward. A landscape framework would provide a quantitative spatial context for analyses of biodiversity at multiple scales and can help resolve how habitat heterogeneity and structure affect biodiversity in soft-sediment environments. Such information may substantively help in sea floor management and conservation.

Radiolarian flux at an IMAGES site at the western margin of the subarctic Pacific and its seasonal relationship to the Oyashio Cold and Tsugaru Warm currents

Seasonal changes of radiolarian flux in the far western area of the Western Subarctic Gyre in the Pacific Ocean were examined based on samples from a sediment-trap experiment deployed at a site off the northern Honshu Island of Japan from June 2002 to May 2003. Warm and neritic water species associated with the Tsugaru Warm Current (TGC), originating from the Japan Sea, were dominant, while the cold-water species associated with the Oyashio Cold Current were relatively few, in spite of the location of the site in the subarctic province. R-mode cluster analysis was used to divide species-specific flux patterns into 5 groups of fauna associated with: (1) the TGC forerunner in June 2002, (2) the TGC main flow from September to November 2002, (3) the neritic water in December 2002, (4) the Oyashio Cold Current in May 2003, and (5) surface productivity in the spring of 2002/2003 together with the TGC in summer 2002.

Stomach contents of common dolphin (Deiphinus sp.) from New Zealand waters

This paper provides the first report of stomach contents of common dolphin (Deiphinus sp.) from New Zealand waters. We examined 53 stomachs from 42 stranded and 11 by‐caught common dolphin from the North Island of New Zealand between 1997 and 2006. Although the diet of by‐caught and stranded common dolphin comprised a diverse range of fish and cephalopod species, the prevalent prey were arrow squid Nototodarus spp., jack mackerel Trachurus spp., and anchovy Engraulis australis. Stranded dolphins that originated from coastal waters, and dolphins by‐caught within neritic waters, fed on both neritic and oceanic prey. Moreover, this mixed prey composition was evident in the diet of common dolphin by‐caught in oceanic waters, suggesting inshore/offshore movements of common dolphin on a diel basis.

Isotopic niches of emperor and Adélie penguins in Adélie Land, Antarctica

The emperor and Adelie penguins are the only two species of penguins that co-occur at high-Antarctic latitudes. We first measured and compared their isotopic niches on the same year in Adelie Land in spring, when the two species co-exist. Emperor and Adelie penguins segregated by their blood isotopic signatures, with adult δ13C values (−24.5 ± 0.2 and −25.4 ± 0.2‰, respectively) suggesting that emperor penguins foraged in more neritic waters than Adelie penguins in spring. At that time, difference in their δ15N values (4.1‰, 12.0 ± 0.4 vs. 7.9 ± 0.1‰) encompassed more than one trophic level, indicating that emperor penguins preyed mainly upon fish (and squids), while Adelie penguins fed exclusively on euphausiids. Second, we compared the food of breeding adults and chicks. The isotopic signatures of adults and chicks of emperor penguins were not statistically different, but δ15N value of Adelie penguin chicks was higher than that of adults (10.2 ± 0.8 vs. 9.0 ± 0.2‰). The difference showed that adult Adelie penguins captured higher trophic level prey, i.e. higher-quality food, for their chicks. Third, the isotopic signatures of Adelie penguins breeding in Adelie Land showed that adults fed on Antarctic krill in oceanic waters in spring and shifted to neritic waters in summer where they preyed upon ice krill for themselves and upon fish and euphausiids for their chicks. A comparison of isotopic niches revealed large overlaps in both blood δ13C and δ15N values within the community of Antarctic seabirds and pinnipeds. The continuum in δ15N values nevertheless encompassed more than one trophic level (5.2‰) from Adelie penguin and crabeater seal to the Weddell seal. Such a broad continuum emphasizes the fact that all Antarctic seabirds and marine mammals feed on varying proportions of a few crustacean (euphausiids) and fish (Antarctic silverfish) species that dominate the intermediate trophic levels of the pelagic neritic and oceanic ecosystems.

Metal and metalloid concentrations in the giant squid Architeuthis dux from Iberian waters

This study investigated 14 trace elements (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V and Zn) in the tissues of the giant squid Architeuthis dux from the Mediterranean and Atlantic Spanish waters. As for other families of cephalopods, the digestive gland and the branchial hearts of Architeuthis showed the highest concentrations of Ag, Cd, Co, Cu, Fe, Ni, Se, V and Zn, highlighting their major role in the bioaccumulation and detoxification processes. With the exception of Hg, the muscles showed relatively low trace element concentrations. Nevertheless, this tissue contained the main proportion of the total As, Cr, Hg, Mn, Ni, and Zn body burden because muscles represent the main proportion of the squid mass. These findings suggest that the metal metabolism is overall the same as other cephalopod families from neritic waters. In females, Zn concentrations increased in the digestive gland with the squid’s weight likely reflecting physiological changes during sexual maturation. Comparing the trace element concentrations in the tissues of Architeuthis, higher Ag, Cu, Hg and Zn concentrations in the squid from the Mediterranean reflected different exposure conditions. In comparison to other meso-pelagic squids from the Bay of Biscay, Cd concentrations recorded in the digestive gland suggest that Architeuthis might feed on more contaminated prey or that it displays a longer life span that other cephalopods.

Redescription of the Tintinnid Stenosemella pacifica Kofoid and Campbell, 1929 (Ciliophora, Spirotricha) Based on Live Observation, Protargol Impregnation, and Scanning Electron Microscopy

The tintinnid ciliate Stenosemella pacifica Kofoid and Campbell, 1929 was occasionally recorded from the pelagial of temperate, subtropical, and tropical neritic waters. Since its cytological features were unknown, the species is redescribed from material collected in the pelagial of the Irish Sea, using live observation, protargol impregnation, and scanning electron microscopy. Furthermore, the species diagnosis is improved to include new characteristics, e.g. the somatic ciliary pattern comprising a ventral, dorsal, and posterior kinety as well as a right, left, and lateral ciliary field. The stomatogenesis of S. pacifica is typical for species with such a complex somatic ciliary pattern: the oral primordium develops hypoapokinetally posterior to the lateral ciliary field. The presence of windows in the lorica collar of Stenosemella ventricosa, the type of the genus, necessitates (i) an improved genus diagnosis, (ii) a synonymization of the genus LuminellaKofoid and Campbell, 1939, and (iii) a transfer of the Luminella species to the genus Stenosemella, including Luminella neocalifornica, which becomes Stenosemella neocalifornica nov. comb. Owing to the lack of a description, Stenosemella crateri is considered a nomen nudum.

First record of Challengeron diodon (Protozoa: Radiolaria: Phaeodaria) from the Aegean Sea

Challengeron diodon is reported for the first time from the north-eastern Aegean Sea. The specimen was collected on 18 February 2001 from subsurface (0.5 m) neritic waters with a depth of 30 m, off Bozcaada Island in the Aegean Sea.The primary hydrographic parameters, temperature 13.8°C, salinity 37.4 psu and dissolved oxygen 7.47 mg l −1 , were recorded at the sampling station. A synonymy is given, together with a brief diagnosis based on morphological characters and supported by micrographs.

First record of Planktoniella sol (Wallich) Schütt, 1893 from Turkish coasts

Planktoniella sol is reported for the first time from Turkish coasts. The specimen was collected on 6 June 2001 with a 55 μm plankton net from subsurface (0.5 m) neritic waters with a depth of 30 m, off Bozcaada Island in the Aegean Sea. The primary hydrographic parameters, temperature, salinity and dissolved oxygen were 18.5 oC, 35.2 psu and 8.54 mg l -1 , respectively. A brief diagnosis based on morphological characters are described in detail and information about its ecological distribution is given.