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PLANKTON NETS

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  • A list of taxa and observations of phytoplankton collected from the SAZ Sense voyage of the Aurora Australis - voyage 3 of the 2006-2007 season. These data are available via the biodiversity database. The collection contains 26 taxa and 562 observations. More information about SAZ SENSE: The overall objective is to characterise Southern Ocean marine ecosystems, their influence on carbon dioxide exchange with the atmosphere and the deep ocean, and their sensitivity to past and future global change including climate warming, ocean stratification, and ocean acidification from anthropogenic CO2 emissions. In particular we plan to take advantage of naturally-occurring, persistent, zonal variations in Southern Ocean primary production and biomass in the Australian Sector to investigate the effects of iron addition from natural sources, and CO2 addition from anthropogenic sources, on Southern Ocean plankton communities of differing initial structure and composition. SAZ-SENSE is a study of the sensitivity of Sub-Antarctic Zone waters to global change. A 32-day oceanographic voyage onboard Australia's ice-breaker Aurora Australis was undertaken in mid-summer (Jan 17 - Feb. 20) 2007 to examine microbial ecosystem structure and biogeochemical processes in SAZ waters west and east of Tasmania, and also in the Polar Frontal Zone south of the SAZ. The voyage brought together research teams from Australasia, Europe, and North America, and was led by the ACE CRC, CSIRO Marine and Atmospheric Research, and the Australian Antarctic Division. The overall goal is to understand the controls on Sub-Antarctic Zone productivity and carbon cycling, and to assess their sensitivity to climate change. The strategy is to compare low productivity waters west of Tasmania (areas with little phytoplankton) with higher productivity waters to the east, with a focus on the role of iron as a limiting micro-nutrient. The study also seeks to examine the effect of rising CO2 levels on phytoplankton - both via regional intercomparisons and incubation experiments.

  • Locations of sampling sites for ASAC project 40 on voyage 7 of the Aurora Australis in the 2001/2002 season. The dataset also contains information on chlorophyll, carotenoids, coccolithophorids and species identification and counts. The voyage acronym was LOSS. There are 203 observations in the collection. These data are available via the biodiversity database. The taxa represented in this collection are (species names at time of data collection, 2001-2002): Acanthoica quattrospina Calcidiscus leptoporus Coronosphaera mediterranea Emiliania huxleyi Gephyrocapsa oceanica Pentalamina corona Syracosphaera pulchra Tetraparma pelagica Triparma columacea subsp. alata Triparma laevis subsp. ramispina Triparma strigata Umbellosphaera tenuis

  • Zooplankton were collected during the winter-spring transition during two cruises of the Aurora Australis: SIPEX in 2007 and SIPEX II in 2012. The umbrella net was 2 metres long, 28 cm2 mouth area and mesh size of 100 um. The net was lowered through holes drilled through the pack ice and lowered to 100 m. It was pulled slowly by hand to the surface, closed and brought back through the ice hole. The contents were preserved in 5% buffered formaldehyde and examined under a Leica M12 in the laboratory. Species were identified to the lowest taxon possible.

  • From the abstract of one of the papers: Three new zooplankton nets have been designed to enable improved collection of zooplankters from ice-covered waters. These nets also enable quantitative sampling of species not adequately sampled by other methods. The first net is a vertical tow net which can be folded like an umbrella to pass through a small ice hole (10 cm). This 'Umbrella Net' takes an integrated sample of zooplankton from all sample depths. The second net is a collapsible free-fall net designed to collect mobile zooplankters capable of avoiding towed nets. This was the only net used which was capable of collecting all furcilia stages of Euphausia crystallorophias from Ellis Fjord, Vestfold Hills, Antarctica. The third net is a diver-operated push net designed to collect zooplankters in the top 15 cm of the under-ice column. Because of the high standing crop of pytoplankton at and near the under-ice surface at particular times of the year, some species of zooplankton tend to congregate there. These species, particularly Paralabidocera antarctica, were collected in great abundance using the push net, but were rare in samples collected by other methods. The fields in this dataset are: species species density site sample

  • Metadata record for data from AAS (ASAC) project 3046. Public The overall objective is to characterise the response of Southern Ocean calcareous zooplankton to ocean acidification resulting from anthropogenic CO2 emissions. Simulated increases in anthropogenic CO2 suggest a reduction in the calcification rates of calcareous organisms. A change in the calcification in the Southern Ocean may cause marine ecosystem shifts and in turn alter the capacity for the ocean to absorb CO2 from the atmosphere. We plan to take advantage of naturally-occurring, persistent, zonal variations in Southern Ocean primary production and biomass to investigate the effects of CO2 addition from anthropogenic sources on Southern Ocean calcareous zooplankton communities. A download file containing an excel spreadsheet of data can be found at the provided URL. Project objectives: The overall objective of this project is to characterise the impacts of recent, primarily anthropogenic, increases in atmospheric CO2 and related changes in the carbonate chemistry on shell formation by calcareous zooplankton in the Australian sector of the Southern Ocean. Calcareous zooplankton (e.g. planktonic foraminifera and pteropods) will be collected using plankton nets at five Southern Ocean localities during high seasonal flux periods. Planktonic foraminiferal and pteropod species and abundances, calcification rates and geochemistry (stable isotope and trace-metal) will be determined on plankton tow samples. Data from recent plankton tow samples will be compared with data deposited historically in the Southern Ocean and recovered from existing deep ocean sediment cores to provides insights about the extent to which modern carbon conditions may have already generated ecological impacts. The project will also provide a baseline of the present-day impact of ocean acidification and can be used to monitor the influence of future anthropogenic CO2 emissions in Southern Ocean ecosystems. Taken from the 2008-2009 Progress Report: Progress against objectives: Because of logistical delays to the Aurora Australis shipping schedule, ship time for this project was deferred to the 2009/2010 season. We have made progress in analysing other materials form previous voyages which will assist in the sampling design for the upcoming season. We are making good progress in planning the upcoming voyage currently scheduled for late 2009. Taken from the 2009-2010 Progress Report: Progress against objectives: Project scientists participated in Voyage 2 of the Aurora Australis, from Hobart to Casey Station in December 2009. Using the Rectangular Midwater Trawl we collected a total of eight plankton samples for examination of calcareous plankton distribution and shell characteristics in the summer Southern Ocean. We were targeting pteropods and planktonic foraminifera, two sets of calcifiers whose calcification response to ocean acidification we had previously reported on in publications in Nature Geoscience, Biogeosciences Discussions, and Deep-Sea Research Part II (in press). Project participants included collaborators from Australian National University and Scottish Natural Heritage, UK. There were low abundance of planktonic calclfiers in this particular seasons and sector, but we consider the initial collection a god start. Samples included approx. 18 pteropods; other samples are still being held by Biosecurity Australia and will be examined as soon as they are released. Other samples have already been sent to researchers at the Australian Institute of Marine Science for genetic (RNA) sequencing. This latter collaboration is a key one which will help answer questions about evolutionary responses to ocean acidification; if there are genotypes which are more or less vulnerable to acidification we may already be seeing selective pressure in the ecosystem and a change in the structure of assemblages as "winners" and "losers" are differentially affected by the impact.

  • Samples were collected at trawl stations (approximately every second CTD station), as well as opportunistically when something interesting was spotted on the Echosounder. The samples were collected with an RMT-1 plankton net and preserved in Steedman's solution. Upon returning to Australia, the samples were passed onto Kerrie Swadling, who split them with a Folsom plankton splitter and counted between 400 and 1300 animals. Every organism was identified to the lowest possible taxon - in the case of copepods, usually to species and stage level. Other taxa are to species wherever possible. All the animals were counted and the results are expressed as abundance per 1000 cubic m. The data in the spreadsheet represent a species x site matrix. The excel spreadsheet entitled 'List of major samples and activities BROKE West.xls' is a summary of the sort of samples that were collected at each station, and the purpose for which they were collected. More detailed notes about the collection of the samples are presented in the Quality field. Further information about the Trawl stations can be found in the parent BROKE-West metadata record. This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679). The fields in these excel spreadsheets are: Station Number Species Date Latitude Longitude Trawl Type Formalin - whether the samples were fixed in formalin IGR - whether the instantaneous growth rate experiment was performed Genetics - preserved in ethanol, samples retained for genetic experiments Frozen - samples frozen at -85 degrees C for chemical analysis POP - samples analysed for Persistent Organic Pollutants Density Contrast - whether the density contrast of the krill were measured Isotopes - samples retained for isotope analysis Frozen DG - digestive gland samples were frozen Ethanol (Squid) - ethanol fixed squid were retained Frozen (Fish) - frozen fish samples were retained Formalin (Fish) - formalin fixed fish samples were retained Ethanol (Fish) - ethanol fixed fish samples were retained Demography - demographic parameters were collected Other - various purposes, occasionally noted in the comments field Comments The spreadsheet 'List of major samples and activities BROKE West.xls' is marked with solid black circles, or empty white circles - the empty white circles represent Euphausia crystallorophias samples. The solid black circles represent Euphausia superba in columns F-K, M and R. In the other columns they will either represent the animal as marked (eg squid), or may be a collection of anything.

  • Antarctic marine diatoms are sensitive to environment change. This project will determine the environmental niches occupied by key diatom species in Antarctic sediments. This will allow climate changes in the past to be interpreted from Holocene sediments and future changes in diatom biogeography to be predicted. Environmental manipulation and competition experiments using diatoms will identify the response of key taxa to environment modification. Understanding the environmental factors governing their distribution and natural variability will provide a basis to interpret palaeo-environment records, and allow predictions how this temperature-sensitive ecosystem will respond to future change. Diatoms for the experiments were collected in 2002 (Aurora Australia, Voyage 1) and 2003 (Aurora Australis, Voyage 1). On each occasion water from the ship's online seawater tap was filtered through a 20 micrometre plankton net for up to one hour into a sample jar. A portion of the sample was preserved in lugol's iodine for later phytoplankton analysis, and the rest of the sample maintained alive in the dark in seawater at a constant low temperature. The live sample is maintained at the AAD for culturing and environment manipulation and competition experiments. Project 2302 Twenty-two water samples were collected from 24/10/02 to 11/11/02, in open seawater between 53 degrees 50 degrees S and 65 degrees 50 degrees S. At each site, the following were recorded from the ship's data logger: latitude, longitude, date, UCT time, local time, water depth, salinity, water temperature, chlorophyll A, UV radiation, and conductivity.

  • Environmental manipulation and competition experiments on cultured and natural diatoms will identify the response of key taxa to environment modification. Understanding the environmental factors governing diatom distribution and natural variability will provide a basis to interpret palaeo-environment records, and allow predictions how this temperature-sensitive ecosystem will respond to future change. Environmental manipulation and competition experiments using diatoms will identify the response of key taxa to environment modification. Understanding the environmental factors governing their distribution and natural variability will provide a basis to interpret palaeo-environment records, and allow predictions how this temperature-sensitive ecosystem will respond to future change. Diatoms for the experiments were collected in 2002 (Aurora Australia, Voyage 1) and 2003 (Aurora Australis, Voyage 1). On each occasion water from the ship's online seawater tap was filtered through a 20 micrometre plankton net for up to one hour into a sample jar. A portion of the sample was preserved in lugol's iodine for later phytoplankton analysis, and the rest of the sample maintained alive in the dark in seawater at a constant low temperature. The live sample is maintained at the AAD for culturing and environment manipulation and competition experiments. Project 2364 Twelve water samples were collected from 23/10/03 to 27/10/03, in open seawater between 60 degrees 45' S and 50 degrees 02' S. At each site, the following data were recorded from the ship's data logger: latitude, longitude, UTC time, local time, water depth, salinity, water temperature, fluorescence, UVB, and conductivity.

  • Crustaceans are an important component of the Antarctic marine ecosystem. Large numbers live in or close to the sea-ice cover, using it as a refuge from predation and a source of food. However, the impact of these animals on algae that grows in the sea ice is unknown. This study is examining the diets and grazing rates of crustaceans in the Antarctic sea-ice ecosystem. These results will aid our understanding of the fate of algal production in sea-ice and will enable the construction of realistic carbon budgets for this ecosystem. This project was commenced in July 2002. A five-week voyage was undertaken on the RV Aurora Australis in October and November 2002, in the vicinity of the Mertz Glacier. Pack ice cores and sub-ice water samples were collected from 8 locations, with 3 to 5 samples of each type collected per site. The cores were sectioned in the field, melted and treated for further analysis. All samples were either preserved or frozen, depending on future requirements, and returned to Australia. Sea ice cores were processed for a range of analyses including microscopy, lipid class and fatty acid determination and stable isotope analysis. A physical description of the pack ice environment (ice type, ice thickness, snow cover, temperature profiles, salinity profiles) was also compiled. A second sampling of the pack ice occurred in Sept-Oct 2003. To date, the salinity and temperature profiles of the pack ice cores have been described and a database compiled of the physical description of the region. A large number of samples (10 sites; 5 ice/water/animal samples per site) was collected and analysis has begun of stable isotopic signatures, fatty acids, chlorophyll a and species identifications. Crustaceans have been sorted under the microscope and initial descriptions of gut contents begun. The third successful sampling trip was to the fast ice surrounding Davis Station during the 2003/04 summer. Two sites were sampled regularly, with a full suite of analyses undertaken. This will provide a temporal component to the project to complement the spatial approach used in the pack ice. Analysis of the fast ice samples is ongoing. Two more sampling trips were carried out during the 2004/05 season. The first in the pack ice offshore from Casey and the second in the fast ice at Casey. The same suite of analyses as listed above was carried out and analyses are ongoing. The download file contains five excel spreadsheets, as well as a word document which further explains data collection.

  • Metadata record for data from ASAC Project 2792 See the link below for public details on this project. Australia's Census of Antarctic Marine Life project. This project is a part of the international "Census of Antarctic Marine Life" (CAML) which is to be conducted during the International Polar Year. It is a collaborative contribution by Australia and France to understand the biodiversity of the oceans surrounding Antarctica, with particular emphasis on the fishes of the eastern part of the Australian Antarctic Territory. The biodiversity data, when added to that obtained by all other nations participating in the CAML, will serve as a robust reference for future examinations of the health of the Southern Ocean, and assist in the conservation and management of the region. 2007/2008 Season A. Plankton 1. The impact of climate change on the plankton. The pelagic ecosystem in the Southern Ocean has taken the brunt of human impact in the region and there is evidence that it is already responding to the effects of global climate change. Plankton is particularly sensitive to climate change and change in their biodiversity is expected to have serious ramifications through the rest of the ecosystem including the survival of higher predators. Some species are adapted to cold waters of Antarctic where some are supposedly cosmopolitan. Which will survive global warming? For how long will there be an Antarctic marine ecosystem? 2. Consequences of environmental change driven by past and current exploitation of living resources in the region, e.g. current scale fish and krill fisheries, fishery by-catch species, recovery of whales and seals. 3. "Ecosystem services" - The role of Southern Ocean plankton as source of human food (krill fishery or other) carbon draw down/mediation, bio-climate feedback though dimethyl sulphide production, bioproducts, sensitive indicators of ocean health, and foundation of the Antarctic marine ecosystem - no plankton, no ecosystem. B. Fish 1. What is the composition of the epipelagic, mesopelagic and benthic ichthyofaunas between the Antarctic Divergence and the coast at Dumont d'Urville? 2. How does the physical and biological structure of the water column, conditions of ice-cover and bottom topography influence the composition and distribution of these ichthyofaunas? 3. What changes in the community structure of the benthic ichthyofauna as a result from the passage of large icebergs? C. Benthos 1. What are the ecological and historical factors affecting benthic diversity? 2. How will benthic communities respond to change? We do not know how sensitive the Antarctic benthic communities are to global climate change, or to localised environmental change as seen in the Antarctic peninsula area, or to the impacts of increased trawling. We have no benchmark to compare the effects of change, although the effects of iceberg scouring and rate of recovery/re-colonisation will serve as a useful analogy for trawling perturbation. 3. What are the links between Antarctic and other faunas? This includes benthic-pelagic coupling, the benthos as a foraging zone for higher predators, and through the Antarctic Circumpolar Current - connections with other southern continents. Field sampling for this project was undertaken in the 2007/08 season, commencing in December and finishing in February 2008. Consequently, sample processing has only been underway for one or two months for plankton and pelagic fish samples. The demersal fish and benthic samples have only recently arrived at the National Natural History Museum (MNHN) in Paris ready for distribution to taxonomists and analysts. However, key CEAMARC collaborators who attended the recent post-field season CEAMARC workshop, Calvi April 2008, agreed that the use of three vessels for the field programme, instead of one ship as originally proposed, more than met expectations should sufficiently address all the objectives. Specifically, we have collected a substantial number of samples with sufficient sampling intensity and resolution to set the required benchmark of biodiversity in the survey for the pelagic, mesobathypelagic and benthic environments. This biodiversity benchmark will allow us to: - Compare changes in biodiversity with future CAML surveys and also with past surveys - Define legacy sites in the survey area for future CAML surveys and interim annual or biennial monitoring programmes to continuing the effects of climate change - Which species are most likely to be affected by climate change and those most likely to survive - Contribute to models looking at long term changes in species composition, ecosystem structure and function, survivorship of key species, effects of global warming, ocean acidification, and impacts on ecosystem service - Studies of the impact of trawling and iceberg scouring on the benthic and demersal communities - Compare pelagic, demersal and benthic communities in the survey area with those in the other CAML survey areas around Antarctica Sufficient samples of plankton, fish and benthos were also collected for genetic and molecular analyses to improve our taxonomic knowledge and address the CAML objective on understanding species radiation. Taken from the 2008-2009 Progress Report: Public summary of the season progress: This project is a part of the international "Census of Antarctic Marine Life" (CAML) conducted during International Polar Year. It is a collaborative contribution by Australia, France, Japan and Belgium to understand the biodiversity of Antarctic waters, with particular emphasis on plankton, fish and benthos of eastern Antarctica. In 2007/08, three ships surveyed this area with a range of traditional and modern sampling gear. The biodiversity data from this survey will be added to other CAML projects to serve as a robust reference for future examinations of the health of the Southern Ocean, and assist in its conservation and management.