ZOOPLANKTONIC ASSOCIATIONS, THROPHIC RELATIONS AND STANDING STOCK OF KRILL AND OTHER GROUPS OF THE COMMUNITY NEAR ELEPHANT ISLAND (FEBRUARY - MARCH 84/85)

Plankton samples were taken near Elephant Island on two oceanographic cruises of “NApOc Barão de Teffé” during the 2nd and 3rd Brazilian Antarctic Expeditions in February-March 1984 and 1985. Oblique hauls were performed with 325 /xm conical nets provided with calibrated flowmeters. Identification of species of zooplankton and phytoplankton of the stomach contents was made and distribution and abudance of zooplanktonic species were studied. Salps pellets were analysed too. The population structure of Euphausiacea of the two cruises was analysed and compared. During February-March 1984 a characteristic zooplanktonic association was found named "Salpidae Water” composed by Salpidae, the dominant group, Euphausiacea, Amphipoda and species of big Copepoda. The krill standing stock was very low and only furcilias V, VI, juveniles, subadults and adults were found. The high number of Salpidae changed the common composition of the antarctic zooplanktonic community excluding small filter — feeding species and allowing the survival of another of big size and carnivorous. The specific composition of samples obtained in February-March 1985 was different showing a drastic diminution of Salpidae and the occurrence of Copepoda populations, species and larvae of small size. The krill standing stock was higher than 1984 and the populations were represented by all larval stages occurred in small numbers.All these differences and variations are discussed. Based on the results of the study of the stomach contents and of the salp pellets and on the data of the other authors a trophic relations outline of the zooplankton community is given. Associações zooplanctônicas, relações tróficas e standing stock do krill e outros grupos da comunidade próximo à Ilha Elefante (Fevereiro — Março 84/85).Durante as 2a e 3a Expedições Brasileiras à Antártica realizadas pelo “NApOc Barão de Teffé” durante os meses de fevereiro e março de 1984 e 1985, foram efetuadas coletas de zooplâncton ao redor da Ilha Elefante. O material foi obtido mediante arrastos obliquos efetuados com redes cônicas de 325 um de abertura de malha, providas de fluxômetros calibrados. Foi identificado o zooplâncton a nível de espécie e seu conteúdo digestivo e os “ pellets” encontrados nas amostras. Foi estudada a distribuição e abundância de cada uma das espécies e foi analisada e comparada a estrutura das populações de Euphausiacea nos dois cruzeiros. Durante a período fevereiro/março de 1984 foi encontrada uma associação característica denominada "Água de Salpas” composta por Salpidae, Euphausiacea, Amphipoda e espécies de grande porte de Copepoda. O "standing stock” de krill apresentou valores muito baixos e as populações estiveram representadas somente por furcilias V, VI, juveniles, subadultos e adultos. A dominância de Salpidae modificou, o que poderia ser chamada de composição comum da comunidade zooplanctônica, excluindo espécies filtradoras pequenas e permitindo a sobrevivência de espécies de maior porte e de carnívoros. A composição específica das amostras obtidas durante o período fevereiro/março de 1985 modificou-se apresentando uma drástica diminuição de Salpidae, o reaparecimento de populações de Copepoda e de espécies e larvas de pequeno tamanho. O “standing stock” de krill foi maior que o registrado no período de fevereiro/março de 1984 e as populações estiveram compostas por indivíduos de todos os estádios larvais a partir de Caliptopis I e ao contrário da campanha anterior, juvenis, subadultos encontram-se em menor número.Todas estas diferenças e variações são discutidas. Em base nos dados obtidos do conteúdo estomacal das espécies zooplanctônicas, dos “pellets” das Salpas e dados de outros autores, é dado um esboço das relações tróficas da comunidade.

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Estimation of the feeding record of pregnant Antarctic minke whales (Balaenoptera bonaerensis) using carbon and nitrogen stable isotope analysis of baleen plates

Polar Biology ◽

10.1007/s00300-021-02816-5 ◽

2021 ◽

Vol 44 (3) ◽

pp. 621-629

Author(s):

Mayuka Uchida ◽

Ippei Suzuki ◽

Keizo Ito ◽

Mayumi Ishizuka ◽

Yoshinori Ikenaka ◽

...

Keyword(s):

Growth Rate ◽

Stable Isotope ◽

Antarctic Krill ◽

Isotope Analysis ◽

Stomach Contents ◽

Annual Growth Rate ◽

Pleuragramma Antarcticum ◽

Minke Whales ◽

Balaenoptera Bonaerensis ◽

The Antarctic

AbstractAntarctic minke whales (Balaenoptera bonaerensis) are migratory capital breeders that experience intensive summer feeding on Antarctic krill (Euphausia superba) in the Southern Ocean and winter breeding at lower latitudes, but their prey outside of the Antarctic is unknown. Stable isotope analyses were conducted on δ13C and δ15N from the baleen plates of ten pregnant Antarctic minke whales to understand the growth rate of the baleen plate and their diet in lower latitudes. Two to three oscillations along the length of the edge of the baleen plate were observed in δ15N, and the annual growth rate was estimated to be 75.2 ± 20.4 mm, with a small amplitude (0.97 ± 0.21 ‰). Bayesian stable isotope mixing models were used to understand the dominant prey that contributed to the isotopic component of the baleen plate using Antarctic krill from the stomach contents and reported values of Antarctic coastal krill (Euphausia crystallorophias), Antarctic silver fish (Pleuragramma antarcticum), Australian krill spp., and Australian pelagic fish spp.. The models showed that the diet composition of the most recent three records from the base of the baleen plates (model 1) and the highest δ15N values in each baleen plate (model 2) were predominantly Antarctic krill, with a contribution rate of approximately 80%. The rates were approximately 10% for Antarctic coastal krill and less than 2.0% for the two Australian prey groups in both models. These results suggest that pregnant Antarctic minke whales did not feed on enough prey outside of the Antarctic to change the stable isotope values in their baleen plates.

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The summer diet of demersal fish at the South Shetland Islands

Antarctic Science ◽

10.1017/s0954102097000527 ◽

1997 ◽

Vol 9 (4) ◽

pp. 407-413 ◽

Cited By ~ 26

Author(s):

Masanori Takahashi ◽

Tetsuo Iwami

Keyword(s):

Marine Ecosystem ◽

Stomach Contents ◽

Demersal Fish ◽

South Shetland Islands ◽

Fish Prey ◽

Shetland Islands ◽

Antarctic Marine ◽

Dietary Component ◽

Gobionotothen Gibberifrons ◽

The Antarctic

The stomach contents of demersal fish in late January 1982 were analysed. Samples were taken at 100, 300 and 500 m depth south of Elephant Island, Bransfield Strait and north of Livingston Island, and at 800 m to the east of Smith Island. Fifty four taxa of fish belonging to 11 families were collected. The diets of 2101 fish representing 38 taxa were examined. These were classified into three categories, fish feeders, krill feeders and benthos feeders. Fish prey species fed on krill and/or benthos. Krill was a major dietary component for 32 (84.2%) out of 38 taxa. Gobionotothen gibberifrons was distributed at all 10 stations (100–800 m in depth) and its diet comprised krill and benthos. The present findings verify the importance of krill in the Antarctic marine ecosystem and indicate that krill is consumed by benthic fish at greater depths than previously reported.

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On the Food of Young Plaice (Pleuronectes platessa)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400009693 ◽

1922 ◽

Vol 12 (4) ◽

pp. 678-687 ◽

Cited By ~ 10

Author(s):

Andrew Scott

Keyword(s):

Present Report ◽

Stomach Contents ◽

Annual Reports ◽

Irish Sea ◽

Pleuronectes Platessa ◽

Larval Stages ◽

Marine Biological Association ◽

Open Sea ◽

Pelagic Eggs ◽

The Irish Sea

The investigation of the food contents in the stomachs of young fishes was included in the scheme of scientific investigations drawn up and initiated by Professor Herdman for the Lancashire Sea Fisheries Committee nearly thirty years ago. The lengthy series of Annual Reports contain here and there accounts of the observations made on the stomach contents of various Pleuronectidæ captured close inshore, and the pelagic stages of other fishes caught from time to time in the plankton tow-nets. No systematic attempt has, however, been made, in connection with the investigation of the Irish Sea, to determine the food of any particular species of fish during the early part of its life history.Other observers working in other areas, notably Dr. Marie Lebour at Plymouth, have added very much to our knowledge of the early food of young fishes. Dr. Lebour's reports, published in the Journal of the Marine Biological Association, Vols. XI and XII, deal with a very large number of larval and post-larval stages of the more important food fishes caught in the tow-nets and young fish-trawl in Plymouth Sound and beyond.The present report gives an account of the food contained in the stomachs of young plaice (Pleuronectes platessa, Linn.) from a few days after hatching to about five months old. The samples examined in April and May were taken from the spawning pond at Port Erin, Isle of Man, where they had hatched from the pelagic eggs spawned by the adult plaice early in 1921. The later stages examined during May to August represented young plaice hatched in the open sea about the same time as those in the pond, and which had made their way close inshore.

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Spatial distribution and secondary production of Copepoda in a tropical reservoir: Barra Bonita, SP, Brazil

Brazilian Journal of Biology ◽

10.1590/s1519-69842007000200007 ◽

2007 ◽

Vol 67 (2) ◽

pp. 223-233 ◽

Cited By ~ 19

Author(s):

MJ. Santos-Wisniewski ◽

O. Rocha

Keyword(s):

Spatial Distribution ◽

Secondary Production ◽

General Pattern ◽

Winter Season ◽

Zooplankton Community ◽

Zooplankton Biomass ◽

Tropical Lakes ◽

Numerical Density ◽

Dominant Group ◽

Tropical Reservoir

The present paper aims to describe the spatial distribution of zooplankton copepods, their biomass and instantaneous secondary production, in Barra Bonita, a large eutrophic, polymitic reservoir (22° 29' S and 48° 34' W) on the Tietê River, of the Paraná basin. Sampling was carried out during two seasons: dry winter and rainy summer. Species composition, age structure and numerical density of each copepod species population were analyzed at 25 sampling stations. Secondary production was calculated for Copepoda, the dominant group in zooplankton communities, taking Calanoida and Cyclopoida separately. Copepoda represented the largest portion of the total zooplankton biomass, the dominant species being Notodiaptomus iheringi among the Calanoida and Mesocyclops ogunnus and Thermocyclops decipiens among the Cyclopoida. The production of Copepoda was higher during the rainy summer (23.61 mgDW.m-3.d-1 in January 1995) than during the dry winter season (14 mgDW.m-3.d-1 in August 1995), following the general pattern of abundance for the whole zooplankton community. Among the copepods, Cyclopoida production was higher than that of Calanoida, a pattern commonly observed for tropical lakes and reservoirs. Barra Bonita copepods are very productive, but there was a great degree of spatial heterogeneity, related to the physical and chemical conditions, particularly the level of nutrients and also to phytoplankton biomass.

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Abiotic parameters and planktonic community of an earthen fish pond with continuous water flow

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x3018 ◽

2019 ◽

Vol 31 ◽

Cited By ~ 1

Author(s):

Lúcia Helena Sipaúba-Tavares ◽

Rodrigo Ney Millan ◽

Érica Camargo Oliveira Capitano ◽

Bruno Scardoelli-Truzzi

Keyword(s):

Water Flow ◽

Zooplankton Community ◽

Information Criterion ◽

Sampling Period ◽

Plankton Community ◽

Dominant Group ◽

Small Water ◽

Management Protocol ◽

Thermotolerant Coliforms ◽

Zooplankton Communities

Abstract Aim Limnological conditions, phytoplankton and zooplankton communities in a fishpond highly affected by management during the dry and rainy seasons are investigated. Methods Water samples were analyzed for physicochemical parameters; soil samples were analyzed for macro- and micro-nutrients, phytoplankton and zooplankton communities, at four sites, during eight months in the rainy and dry seasons. Distance-based linear model (DISTLM) was applied with Akaike Information Criterion (AIC), where the influence of environmental variables in the variation of phytoplankton and zooplankton composition could be assessed and the best model could be selected. Results The multiparameter test revealed that variables pH, TSS and TP better explain the composition of the biotic community (AICc = 45.6; R2 = 0.80). Chlorophyceae was the dominant group with 32 taxa, or rather, 75-85% of total phytoplankton, with high density at 2,365-4,180 ind.L-1 during the sampling period. Rotifera was the most abundant group in the zooplankton community during the two seasons, except at IW2 during the dry season, when Copepoda had a higher density, namely, 52% of total zooplankton community at this site. Conclusions The contribution of allochthonous material to the fishpond during the two seasons mainly consists of macro- and micro-nutrients and thermotolerant coliforms that influenced the plankton community and enhanced high Cyanobacteria density in the rainy season. Plankton community in the studied pond was characteristic of small water bodies. Management protocol in places with continuous water flow according to the region may be an important tool to optimize and to avoid risks in fish production.

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Dynamics of the parasite Marteilia refringens (Paramyxea) in Mytilus galloprovincialis and zooplankton populations in Alfacs Bay (Catalonia, Spain)

Parasitology ◽

10.1017/s0031182007003009 ◽

2007 ◽

Vol 134 (11) ◽

pp. 1541-1550 ◽

Cited By ~ 24

Author(s):

N. CARRASCO ◽

I. LÓPEZ-FLORES ◽

M. ALCARAZ ◽

M. D. FURONES ◽

F. C. J. BERTHE ◽

...

Keyword(s):

Mytilus Galloprovincialis ◽

Zooplankton Community ◽

Infection Process ◽

Ostrea Edulis ◽

Decapod Crustaceans ◽

Intermediate Hosts ◽

Experimental Transmission ◽

Larval Stages ◽

Delta De L'ebre ◽

Euterpina Acutifrons

SUMMARYSince the first description of Marteilia refringens (Paramyxea) in flat oysters Ostrea edulis in 1968 in the Aber Wrach, Brittany (France), the life-cycle of this parasite has remained unknown. However, recent studies, conducted in the ‘claire’ system, have proposed the planktonic copepod Acartia grani as a potential intermediate host for the parasite. Nevertheless, experimental transmission of the parasite through the copepod has failed. Recent studies in this field have reported the presence of the parasite in zooplankton from the bays of the Delta de l'Ebre, a more complex and natural estuarine environment than that of the claire. As a result, 2 new Marteilia host species were proposed: the copepods Oithona sp. (Cyclopoida) and an indeterminate Harpaticoida. Consequently, the objective of the present work was to study the dynamics of Marteilia in the zooplankton community from one of the bays, Alfacs Bay, as well as the dynamics of the parasite in cultivated mussels during 1 complete year. Six different zooplankton taxa appeared to be parasitized by M. refringens, including copepods (3 Calanoida, Acartia discaudata, A. clausi and A. italica; 1 Cyclopoida, Oithona sp.; and 1 Harpacticoida, Euterpina acutifrons), and larval stages of decapod crustaceans (zoea larvae of Brachyura, probably Portumnus sp.). These taxa are thus proposed as new subjects for study, since they could be intermediate hosts in the infection process of mussels by Marteilia.

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The diversity and longitudinal changes of zooplankton in the lower course of a large, regulated European river (the lower Vistula River, Poland)

Biologia ◽

10.2478/s11756-013-0263-6 ◽

2013 ◽

Vol 68 (6) ◽

Cited By ~ 4

Author(s):

Paweł Napiórkowski ◽

Teresa Napiórkowska

Keyword(s):

Species Diversity ◽

Zooplankton Community ◽

Abundant Species ◽

Main Channel ◽

Brachionus Calyciflorus ◽

Longitudinal Variation ◽

Zooplankton Species ◽

Larval Stages ◽

Vistula River ◽

Brachionus Angularis

AbstractThe diversity and longitudinal variation of zooplankton in the lower Vistula River were analyzed. Samples were taken from 40 stations located along a 272-km long section of the lower river course. During the study the unique technique of taking samples from “the same water” was used. The zooplankton community was dominated by rotifers and nauplii — larval stages of copepods. The most abundant species were: Brachionus angularis, Brachionus calyciflorus and Brachionus budapestiensis. The zooplankton species diversity in the main channel of the lower Vistula River was similar to other large European rivers; however, its abundance was lower. The diversity, abundance and biomass of potamoplankton steadily decreased downstream. This could be related both to scarcity of storage zones for potamoplankton development in the river due to the extensive regulation processes, and changes in hydrological conditions of the main channel (by the straightening of riverbed) where the samples were collected.

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Diet components in the food of Antarctic ascidians living at low levels of primary production

Antarctic Science ◽

10.1017/s0954102004001890 ◽

2004 ◽

Vol 16 (2) ◽

pp. 123-128 ◽

Cited By ~ 23

Author(s):

MARCOS TATIÁN ◽

RICARDO SAHADE ◽

GRACIELA B. ESNAL

Keyword(s):

Primary Production ◽

Stomach Contents ◽

Food Sources ◽

Potter Cove ◽

Mean Values ◽

Faecal Pellets ◽

Wide Range ◽

The Rich ◽

Wind Mixing ◽

The Antarctic

Coupling between pelagic and benthic systems has been described in numerous shallow water communities. In Potter Cove, where pelagic primary production is low (not only during the Antarctic winter but also during the summer), the rich benthic community present there must depend on other food sources than phytoplankton. Over a year-round period we determined the abundance of the different seston particles which constituted the stomach contents of the Antarctic ascidian Cnemidocarpa verrucosa (Lesson, 1830) at Potter Cove. Stomach repletion was highest in November and lowest in June. Ascidians took in a wide range of particles from large detritus (macroalgal debris and faecal pellets) to minute particles < 5 μm. Large detritus and minute particles together represent the main percentage of contents throughout the year (mean 91%). Diatoms were a low percentage (mean 4.5%). Unidentified flagellates, dinoflagellates and coccolithophorids were scarce, with mean values lower than 4%. Among diatoms benthic species were more abundant in summer and pelagic ones prevailed from March to November. Resuspension of benthic material due to wind mixing and the input of allochthonous particles by currents are important mechanisms that ensure food for ascidians and the community of suspension feeders in Potter Cove.

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Spatio-Temporal Assessment of Zooplankton Fauna of Uta Ewa Estuary, Akwa Ibom State, Nigeria.

Omni-Akuatika ◽

10.20884/1.oa.2020.16.2.822 ◽

2020 ◽

Vol 16 (2) ◽

pp. 151

Author(s):

Udeme Effiong Jonah ◽

Emeka Donald Anyanwu ◽

Diane Akudo Avoaja

Keyword(s):

Water Quality ◽

Water Temperature ◽

Anthropogenic Activities ◽

Water System ◽

Zooplankton Community ◽

Dominant Group ◽

Significant Difference ◽

Spatio Temporal ◽

Taxonomic Groups ◽

Temporal Assessment

Estuaries are influenced by the mixture of river water with seawater; creating unique ecosystems with several physical and chemical processes affecting the water quality. Spatial and temporal assessment of the composition, abundance, and distribution of zooplankton fauna of Uta Ewa Estuarine water system was carried out between May 2019 and February 2020 to assess the effects of anthropogenic activities on the zooplankton assemblage. Water and Zooplankton samples were collected from three (3) stations using standard procedures. Some parameters like water temperature, dissolved oxygen, hydrogen-ion, electrical conductivity, and turbidity were determined in-situ. The ranges of the physico-chemical parameters were: water temperature (24.9-25.3oC), EC (62.3-70.9mS/m), pH (6.5-6.7), turbidity (12.0-28.0NTU), DO (3.8-4.7mg/L), BOD (2.3-3.2mg/L), phosphate (3.2-5.2mg/L), and nitrate (3.0-6.3mg/L). ANOVA showed a significant difference (p<0.05) in the spatial and temporal means values of some parameters. A total of 1,067 individuals from 30 zooplankton taxa and 4 taxonomic groups were recorded. Rotifers (33.4%) were the dominant group, followed by protozoa (32.9%), copepods (20.9%) and cladocerans (13.8%). Station 1 had the highest abundance (388 individuals), station 2 (303 individuals) and station 3(375 individuals). The higher number of individuals (193) was recorded in August 2019. The biodiversity indices pointed to slightly polluted to stable environment. This study showed that the water quality and zooplankton community was influenced by anthropogenic activities both spatially and temporally but season also played a major role in the temporal variation. In conclusion, the water quality was deteriorating due to anthropogenic activities, which in turn affected the structure of zooplankton community. Keywords: Abundance, Assessment, Zooplankton, Physicochemical, Estuary

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Variability of the food potential of the Kerch strait and the black sea pre-strait zone as a prospective area for the development of mollusks Mariculture

E3S Web of Conferences ◽

10.1051/e3sconf/202125804007 ◽

2021 ◽

Vol 258 ◽

pp. 04007

Author(s):

Nataliy Sitnik

Keyword(s):

Black Sea ◽

Suspended Matter ◽

Zooplankton Community ◽

The Black Sea ◽

Dynamic Factor ◽

Total Biomass ◽

Algal Flora ◽

High Productivity ◽

Larval Stages ◽

Kerch Strait

Based on the data of integrated observations, the variability of phytoplankton, the amount of suspended organic matter and zooplankton of the pelagic zone of the Kerch Strait and the pre-strait zone of the Black Sea is considered. The algal flora of the entire Black Sea, the Kerch Strait and the pre-strait is characterized by the predominance of diatoms over pyridineas (pyrrophytes or dinoflagellates). The study of the species range, number and biomass of the phytoplankton community during several periods of the year showed that its dynamics is largely dependent on seasonal weather changes (climate). In the process of phytoplankton development, several phases of autogenic succession were revealed. It is expressed in a sequential change in phytoplankton forms, changes in its abundance and biomass typical of the eastern shelf of the Black Sea. The zooplankton community of the Kerch Strait is represented by micro-, meso- and macro- zooplankton typical of the Black Sea. Microzooplankton is represented by zooflagellates and protozoa, as well as by early larval stages of planktonic crustaceans, apendicularia and mollusks. Its total biomass averages about 80 mg/m3.The above analysis of the collected material allows us to conclude that the distribution of suspended matter and larvae is related primarily to the peculiarities of water circulation in the strait. In the case of low concentrations of larvae, the dynamic factor can be decisive in the process of sedimentation intensity. The amounts of suspended matter can reach 20 mg/m3, which is 2-3 times higher than on average for the Black Sea. It further demonstrates the high productivity of waters and the prospects of the latter to be the area for commercial growing of mussels.

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