Rapid Change of Foraminiferal Communities and Assemblages in the Setiu Estuary, Terengganu, Malaysia: Anthropogenic Drivers

In November 2013, an artificial inlet was opened in the barrier island that separates the waters of the Setiu estuary-lagoon system of Terengganu, Malaysia, from the South China Sea. The inlet was opened to stabilize salinity and improve tidal flushing so that fish-farming could be expanded but, as a result, another inlet that was open in 2009 closed naturally by November 2015. These geomorphic changes caused salinity in the Setiu estuary to undergo significant increase from November 2013 to November 2015. To investigate the foraminiferal response to these salinity changes, 24 of 56 foraminiferal sampling stations occupied in 2009 were resampled in 2016. Salinity increased throughout the estuary from 2009 (mean 6.6, range 0–28.7) to 2016 (mean 33.3, range 23.3–34.8) and foraminiferal live communities and dead assemblages changed. Diversity of dead assemblages increased significantly (mean number of species/sample in 2009 = 10.9 versus 2016 = 25.8) as the result of transport of specimens of nearshore, neritic species into the estuary through the new inlet. Diversity of live populations increased slightly (2008 = 4.6 versus 2016 = 6.2). Dead assemblages and live populations dominated by agglutinated foraminifera in 2009 were co-dominated by calcareous hyaline foraminifera in 2016. Live calcareous porcelaneous foraminifera were rare in 2009 and 2016, but dead miliolids were more common and more widespread in 2016. Stations in higher energy environments immediately adjacent to the two different inlets of 2009 and 2016 were characterized by few live or dead foraminiferal tests. Changes in foraminiferal diversity, abundance, and distribution between the two sampling times of early June 2009 and late May 2016 were significant and took place within the 30-month interval between November 2013 (when the artificial inlet was opened) and May 2016 when samples were collected, but they most likely occurred over a shorter interval of time.

About first records of tintinnid Tintinnopsis mortensenii Schmidt, 1902 (Spirotrichea, Choreotrichia, Tintinnida, Codonellidae) in the Sevastopol Bay plankton (Black Sea)

The tintinnid ciliate Tintinnopsis mortensenii Schmidt, 1902 was detected in estuary of the Chernaya River in 2009 for the first time. Next time it was recorded in August 2016 at the mouth of Sevastopol Bay. This neritic species is rare and demonstrate tropical occurrence. Morphological differences from the close Black Sea species T. campanula are shown.

Deep-water ostracods from the Middle Anisian (Reifling Formation) of the Northern Calcareous Alps (Austria)

A diverse silicified ostracod aassemblage from Middle Anisian, Middle Triassic, intra-shelf basin deposits (Reifling Formation) is described. It comprises 32 species, of which 5 are new species (Bairdia biforis n. sp., B. schneebergiana n. sp., Mirabairdia praepsychrosphaerica n. sp., M. plurispinosa n. sp., Bairdiacypris aequisymmetrica n. sp.). The assemblage consists of both neritic species and deep-water taxa which have been considered as representatives of the ‘Thuringian Ecotype’ or the ‘Palaeopsychrospheric Fauna’. Lithofacies, palaeogeographical setting and taxonomic composition are suggestive of a deep neritic to upper bathyal depositional environment. ‘Archaic’ faunal elements are relatively rare and include the genera Spinomicrocheilinella and Processobairdia, which were formerly known only from the Palaeozoic and are now recorded for the first time from the Mesozoic.

Environmental driving forces determining the epipelagic decapod larval community distribution in the Balearic Sea (western Mediterranean)

The decapod larvae community inhabiting the Balearic Sea surface waters was studied from plankton surveys carried out in the spring and summer of 2004 and 2005 between 38°N 0.5°E and 42°N 6°E. A total of 84 taxa were identified, from seven taxonomic orders. The mean larval densities varied from 0.01-240 (±11.69) individuals 100 m−3in 2004 to 0.40-600 (±26.89) individuals 100 m−3in 2005. The analysis of larval spatial patterns in relation to the observed inter-annual environmental variability indicated that they were associated with the different hydrodynamic conditions. In 2004, mesoscale gyres, both anticyclonic and cyclonic, influenced the surface larval distribution by trapping and retaining larvae near the islands, and these larvae constituted an identifiable community different from a second one occupying the oceanic area, characterized by the presence of mesopelagic species larvae. In 2005, most of the area was occupied by resident surface Atlantic waters, which hindered the northern progression of fresher recent Atlantic waters. This environmental homogeneity resulted in a less contrasting scenario, and a unique community including larvae both of neritic and oceanic decapod species was found in most stations. The contrasting hydrographical situations studied in these years allowed to detect shift boundaries in the larval distribution of neritic species, indicating that the hydrographically more homogeneous years may lead to a higher dispersion of neritic decapod larvae.

Paleoecology of the K-Pg mass extinction survivor Guembelitria (Cushman): isotopic evidence from pristine foraminifera from Brazos River, Texas (Maastrichtian)

The late Maastrichtian sediments of the Mullinax-1 and Mullinax-3 boreholes from Brazos River, Texas, offer pristine material. These cores are prime candidates for providing an extraordinary window into the ecology of Guembelitria, a key genus in the K/Pg mass extinction event, as well as information on the habitats of other neritic species. Stable oxygen and carbon isotope analyses were performed on six planktic species (Guembelitria cretacea, Globigerinelloides asper, Heterohelix globulosa, Paraspiroplecta navarroensis, Pseudoguembelina costulata, Rugoglobigerina rugosa) and three benthic genera (Gavelinella, Cibicides, and Lenticulina). Our records support the contention that Guembelitria was fully planktic, as indicated by its δ18O values, which overlap the other planktic species, despite its possible origin from a tychopelagic benthic ancestor. However, Guembelitria is distinctly ranked very low in δ13C values, which overlap the benthic records. The anomalously low δ13C values of Guembelitria may represent an isotopic disequilibrium due to fast shell growth, like in its modern analogue Gallitellia vivans. Another explanation may be that these values are attributable to a neustonic life mode in the uppermost part of the oceans, where photosynthesis is inhibited by high UV and the near absence of nutrients. Because these waters are not photosynthetically depleted, calcification using carbon directly from these waters should yield δ13C values consistent with those found in Guembelitria. The ecological strategy that Guembelitria species used to deal with the nutrient-poor surface-water environments was an opportunistic blooming during stressful times of Maastrichtian global warming events and later during the K-Pg catastrophe.

Provisioning and Growth Rates of Shy Albatrosses at Albatross Island, Tasmania

We used electronic weighing platforms inside artificial nests to remotely study chick provisioning and growth in Shy Albatrosses (Thalassarche cauta) at Albatross Island, Tasmania, from 1996 to 1998. Pairs of birds concurrently carried radio-transmitters, allowing each meal to be attributed to an individual parent. Chicks received relatively small meals (372 g) once every 22 hr, and were provisioned at 392 g day−1 from the end of the brooding period to fledging. Meal size increased with chick age while the feeding frequency decreased, such that chicks were provisioned at a relatively constant rate until reaching peak mass (5.5 kg at 109 days). Provisioning subsequently declined and chicks lost mass, leaving the nest after 127 days weighing 5.0 kg. Male chicks were fed for 10 days longer than females, they received 27% more food, grew faster, and attained higher peak and fledging masses. Between hatching and fledging, overall food consumption by chicks was estimated at 44.9 kg. Rates of chick provisioning and growth were constant between years. Overall, adult males and females provisioned chicks equally. However, large imbalances were often observed within pairs, and in some cases one parent adjusted its provisioning schedule to compensate for its mate. Adults generally decreased provisioning rates when chicks were well fed, but only some elevated their feeding frequency when faced with greater demands. The ability to increase provisioning to hungry chicks contrasts with expectations from studies of other neritic species.Alimentación y Tasa de Crecimiento de Pichones de Thalassarche cauta en la Isla AlbatrosResumen. Utilizamos balanzas electrónicas ubicadas dentro de nidos artificiales para estudiar a distancia la alimentación y el crecimiento de polluelos de Thalassarche cauta entre 1996 y 1998 en la Isla Albatros, Tasmania. Acoplamos radio transmisores a parejas de aves de manera que cada episodio de alimentación en el nido podría ser atribuido a uno de los padres. Los pichones recibieron comidas relativamente pequeñas (372 g) una vez cada 22 horas y recibieron 392 g de alimento por día desde el final del período en que las aves empollan hasta el abandono del nido. Mientras que el tamaño de las comidas aumentó con la edad de los pichones, la frecuencia de alimentación disminuyó. Al principio los pichones fueron alimentados a una tasa relativamente constante hasta alcanzar un pico en su peso (5.5 kg a los 109 días). Después de esto, la tasa de alimentación se redujo, generando una disminución en el peso hasta llegar a 5.0 kg al momento de abandonar el nido después de 127 días. Los polluelos machos fueron alimentados durante 10 días más que las hembras, recibieron 27% más alimento, crecieron más rápidamente y alcanzaron pesos superiores en el momento pico y al salir del nido. Desde la eclosión hasta el abandono del nido, el consumo total estimado de alimento por parte de los pichones fue de 44.9 kg. Las tasas de alimentación y crecimiento de los polluelos fueron constantes entre años. En general, los machos y hembras adultos alimentaron por igual a los pichones. Sin embargo, se observaron grandes desbalances entre los miembros de algunas parejas. En algunos casos, uno de los padres ajustó su tasa de alimentación al polluelo para compensar la de su pareja. Los adultos generalmente disminuyeron las tasas de suministro de alimento cuando los pichones estaban bien alimentados pero sólo algunos de ellos aumentaron la frecuencia de alimentación cuando recibieron demandas superiores. La capacidad de incrementar la tasa de alimentación de polluelos hambrientos contrasta con lo esperado a partir de estudios en otras especies neríticas.

Distribution, abundance and biomass of Chaetognaths off São Sebastião region, Brazil in February 1994

The distribution, abundance, biomass, population structure and feeding habits of chaetognaths collected off São Sebastião region, Brazil, in February 1994 are described. Bongo nets were hauled obliquely to collect zooplankton samples. Forty-three samples obtained with the 333 urn mesh were analysed. In this study, 7 chaetognath species belonging to two genera were identified. Sagitta friderici, S. tenuis and S. bipunctata were grouped into the neritic category, and Sagitta enflata, S. hispida, S. minima and Krohnita pacifica into the semi-neritic group. The analysis of the community structure distinguished 3 zones: 1) a nearshore zone evidenced by low richness; 2) an offshore zone evidenced by higher number of species and 3) another offshore zone, located south and south-westward of São Sebastião Island, characterised by higher richness but with dominance of one species. The nearshore zone was dominated by the neritic species S. friderici and S. tenuis, whereas the offshore zone was dominated by S. enflata. Abundance and biomass increase from nearshore toward offshore zones by about two orders of magnitude. Gut content analysis revealed over 90% of empty guts. The chaetognath population was composed mainly of juveniles. The diets among the different chaetognath species was very similar, composed mostly of small copepods and appendicularians.

Seasonal relative abundance of fish larvae inshore at Îles Kerguelen, Southern Ocean

Ichthyoplankton sampling was conducted seasonally with 36 surveys between spring 1989 and spring 1992 in four bays in the Kerguelen archipelago: Morbihan, Baleiniers, Choiseul and Audierne. Golfe des Baleiniers is open to the shelf whereas Choiseul and Audierne are long fjords. Golfe du Morbihan is a very large and protected area open to the shelf at its eastern end. Larvae of neritic species were abundant outside whereas larvae of inshore species were abundant inside the Golfe du Morbihan. Larval Lepidonotothen squamifrons were detected during summer every year whereas larvae of Champsocephalus gunnari were observed in only two years, mainly in the northern coastal zone. For both species, our results support coastal spawning grounds in addition to those on the shelf slope. Larvae of the mesopelagic fish Krefftichthys anderssoni were dominant primarily during winter; this was linked to homogenisation of the water column over the shelf and the coastal zone. Larvae of Notothenia cyanobrancha were present throughout the year everywhere, which is linked to the year long pelagic earlylife-history phase.