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The Kerguelen Plateau: Marine Ecosystem + Fisheries
THE KERGUELEN PLATEAU: MARINE ECOSYSTEM + FISHERIES Proceedings of the Second Symposium Kerguelen plateau Marine Ecosystems & Fisheries • SYMPOSIUM 2017 heardisland.antarctica.gov.au/research/kerguelen-plateau-symposium Important readjustments in the biomass and distribution of groundfish species in the northern part of the Kerguelen Plateau and Skiff Bank Guy Duhamel1, Clara Péron1, Romain Sinègre1, Charlotte Chazeau1, Nicolas Gasco1, Mélyne Hautecœur1, Alexis Martin1, Isabelle Durand2 and Romain Causse1 1 Muséum national d’Histoire naturelle, Département Adaptations du vivant, UMR 7208 BOREA (MNHN, CNRS, IRD, Sorbonne Université, UCB, UA), CP 26, 43 rue Cuvier, 75231 Paris cedex 05, France 2 Muséum national d’Histoire naturelle, Département Origines et Evolution, UMR 7159 LOCEAN (Sorbonne Université, IRD, CNRS, MNHN), CP 26, 43 rue Cuvier, 75231 Paris cedex 05, France Corresponding author: [email protected] Abstract The recent changes in the conservation status (establishment and extension of a marine reserve) and the long history of fishing in the Kerguelen Islands exclusive economic zone (EEZ) (Indian sector of the Southern Ocean) justified undertaking a fish biomass evaluation. This study analysed four groundfish biomass surveys (POKER 1–4) conducted from 2006 to 2017 across depths ranging from 100 to 1 000 m. Forty demersal species were recorded in total and density distributions of twenty presented. However, only seven species account for the majority of the biomass (96%). Total biomass was 250 000 tonnes during the first three surveys (POKER 1–3), and 400 000 tonnes for POKER 4 due to a high catch of marbled notothen (Notothenia rossii) and mackerel icefish (Champsocephalus gunnari) (accounting for 44% and 17% of the 400 000 tonnes biomass respectively). -
The Ross Sea Dipole - Temperature, Snow Accumulation and Sea Ice Variability in the Ross Sea Region, Antarctica, Over the Past 2,700 Years
Clim. Past Discuss., https://doi.org/10.5194/cp-2017-95 Manuscript under review for journal Clim. Past Discussion started: 1 August 2017 c Author(s) 2017. CC BY 4.0 License. The Ross Sea Dipole - Temperature, Snow Accumulation and Sea Ice Variability in the Ross Sea Region, Antarctica, over the Past 2,700 Years 5 RICE Community (Nancy A.N. Bertler1,2, Howard Conway3, Dorthe Dahl-Jensen4, Daniel B. Emanuelsson1,2, Mai Winstrup4, Paul T. Vallelonga4, James E. Lee5, Ed J. Brook5, Jeffrey P. Severinghaus6, Taylor J. Fudge3, Elizabeth D. Keller2, W. Troy Baisden2, Richard C.A. Hindmarsh7, Peter D. Neff8, Thomas Blunier4, Ross Edwards9, Paul A. Mayewski10, Sepp Kipfstuhl11, Christo Buizert5, Silvia Canessa2, Ruzica Dadic1, Helle 10 A. Kjær4, Andrei Kurbatov10, Dongqi Zhang12,13, Ed D. Waddington3, Giovanni Baccolo14, Thomas Beers10, Hannah J. Brightley1,2, Lionel Carter1, David Clemens-Sewall15, Viorela G. Ciobanu4, Barbara Delmonte14, Lukas Eling1,2, Aja A. Ellis16, Shruthi Ganesh17, Nicholas R. Golledge1,2, Skylar Haines10, Michael Handley10, Robert L. Hawley15, Chad M. Hogan18, Katelyn M. Johnson1,2, Elena Korotkikh10, Daniel P. Lowry1, Darcy Mandeno1, Robert M. McKay1, James A. Menking5, Timothy R. Naish1, 15 Caroline Noerling11, Agathe Ollive19, Anaïs Orsi20, Bernadette C. Proemse18, Alexander R. Pyne1, Rebecca L. Pyne2, James Renwick1, Reed P. Scherer21, Stefanie Semper22, M. Simonsen4, Sharon B. Sneed10, Eric J., Steig3, Andrea Tuohy23, Abhijith Ulayottil Venugopal1,2, Fernando Valero-Delgado11, Janani Venkatesh17, Feitang Wang24, Shimeng -
The Ross Sea: a Valuable Reference Area to Assess the Effects of Climate Change
IP (number) Agenda Item: CEP 7e, ATCM 13 Presented by: ASOC Original: English The Ross Sea: A Valuable Reference Area to Assess the Effects of Climate Change 1 IP (number) Summary International Panel on Climate Change models predict that the Ross Sea will be the last portion of the Southern Ocean with sea ice year round. Currently, the Ross Sea ecosystem is considered to be relatively little affected by direct human-related impacts other than the past exploitation of marine mammals along its slope and the recent exploratory Antarctic toothfish fishery. The indirect human impacts of CO2 pollution on melting ice and ocean acidification have yet to be felt. The Ross Sea - with its several very long biotic and hydrographic data sets - constitutes an important reference area to gauge the ecosystem effects of climate change and distinguish those effects from the effects of current fisheries, tourism, and historic overexploitation and recovery or lack of recovery of some seal, whale, and fish populations elsewhere. This, in conjunction with a range of other scientific and biological reasons that has been laid out in prior ASOC papers, underpins why the Ross Sea should be included as a key component in the network of marine protected areas currently being considered for the Southern Ocean by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). 1. Introduction Over the past few years, ASOC has put forward a number of papers making the ‘science case’ for supporting full protection of the Ross Sea slope and shelf,1 in the context of establishing an important component of a representative network of MPAs in the Southern Ocean.2 This paper focuses on the climate reference zone potential of the Ross Sea. -
Can Fishing in the Ross Sea Be Sustainable? Leo Salas, Ph.D
Can fishing in the Ross Sea be sustainable? Leo Salas, Ph.D. [email protected] Humans have removed 90% of Besides being the largest fish in feasible metrics to monitor the big fish from every ocean in Antarctic waters, toothfish is also include seal population numbers, the planet, except for the among the most energy-rich. breeding propensity, diving effort, Southern Ocean, especially the Because of these two factors, It and toothfish consumption rate. Ross Sea. But that may be has been suggested that toothfish changing. Since 2003, the largest may be critical for mass recovery Main Points (more than twice as big as the in mother seals. next species) fish in Antarctica is Weddell seals may not Using all the scientific evidence being removed from the Ross Sea. recover sufficiently from available, the team constructed a nursing their pups without That fish is the Antarctic toothfish, the largest and model to determine how much toothfish, usually sold as Chilean among the most energy- energy the seals must consume seabass. The fishery target is to dense fish in Antarctic waters. reduce the total number of adult during the recovery period to maintain population numbers. The toothfish fishery is toothfish by 50% over a 35 year likely already adversely That model was coupled with a period. affecting seal populations. simulation of prey consumption The fishery may be Is the fishery affecting the to establish the role of toothfish sustainable at lower Antarctic ecosystem? If so, how, in sustaining seal populations. extraction rates. Monitoring of seal and by how much? A team of The results show that some populations is important to researchers, led by Point Blue ensure this fishery is consumption of toothfish is Conservation Science, sought to sustainable. -
S41467-018-05625-3.Pdf
ARTICLE DOI: 10.1038/s41467-018-05625-3 OPEN Holocene reconfiguration and readvance of the East Antarctic Ice Sheet Sarah L. Greenwood 1, Lauren M. Simkins2,3, Anna Ruth W. Halberstadt 2,4, Lindsay O. Prothro2 & John B. Anderson2 How ice sheets respond to changes in their grounding line is important in understanding ice sheet vulnerability to climate and ocean changes. The interplay between regional grounding 1234567890():,; line change and potentially diverse ice flow behaviour of contributing catchments is relevant to an ice sheet’s stability and resilience to change. At the last glacial maximum, marine-based ice streams in the western Ross Sea were fed by numerous catchments draining the East Antarctic Ice Sheet. Here we present geomorphological and acoustic stratigraphic evidence of ice sheet reorganisation in the South Victoria Land (SVL) sector of the western Ross Sea. The opening of a grounding line embayment unzipped ice sheet sub-sectors, enabled an ice flow direction change and triggered enhanced flow from SVL outlet glaciers. These relatively small catchments behaved independently of regional grounding line retreat, instead driving an ice sheet readvance that delivered a significant volume of ice to the ocean and was sustained for centuries. 1 Department of Geological Sciences, Stockholm University, Stockholm 10691, Sweden. 2 Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77005, USA. 3 Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA. 4 Department -
Ice Production in Ross Ice Shelf Polynyas During 2017–2018 from Sentinel–1 SAR Images
remote sensing Article Ice Production in Ross Ice Shelf Polynyas during 2017–2018 from Sentinel–1 SAR Images Liyun Dai 1,2, Hongjie Xie 2,3,* , Stephen F. Ackley 2,3 and Alberto M. Mestas-Nuñez 2,3 1 Key Laboratory of Remote Sensing of Gansu Province, Heihe Remote Sensing Experimental Research Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; [email protected] 2 Laboratory for Remote Sensing and Geoinformatics, Department of Geological Sciences, University of Texas at San Antonio, San Antonio, TX 78249, USA; [email protected] (S.F.A.); [email protected] (A.M.M.-N.) 3 Center for Advanced Measurements in Extreme Environments, University of Texas at San Antonio, San Antonio, TX 78249, USA * Correspondence: [email protected]; Tel.: +1-210-4585445 Received: 21 April 2020; Accepted: 5 May 2020; Published: 7 May 2020 Abstract: High sea ice production (SIP) generates high-salinity water, thus, influencing the global thermohaline circulation. Estimation from passive microwave data and heat flux models have indicated that the Ross Ice Shelf polynya (RISP) may be the highest SIP region in the Southern Oceans. However, the coarse spatial resolution of passive microwave data limited the accuracy of these estimates. The Sentinel-1 Synthetic Aperture Radar dataset with high spatial and temporal resolution provides an unprecedented opportunity to more accurately distinguish both polynya area/extent and occurrence. In this study, the SIPs of RISP and McMurdo Sound polynya (MSP) from 1 March–30 November 2017 and 2018 are calculated based on Sentinel-1 SAR data (for area/extent) and AMSR2 data (for ice thickness). -
Marine Ecology Progress Series 502:281
Vol. 502: 281–294, 2014 MARINE ECOLOGY PROGRESS SERIES Published April 15 doi: 10.3354/meps10709 Mar Ecol Prog Ser Foraging behaviour of southern elephant seals over the Kerguelen Plateau Malcolm O’Toole1,*, Mark A. Hindell1, Jean-Benoir Charrassin2, Christophe Guinet3 1Institute of Marine and Antarctic Studies, University of Tasmania, Hobart 7001, Australia 2Muséum National d’Histoire Naturelle, Paris 75231, France 3Marine Predator Department, Centre Biologique de Chize, Villiers en Bois 79360, France ABSTRACT: A total of 79 (37 juvenile male, 42 adult female) southern elephant seals Mirounga leonina from the Kerguelen Islands were tracked between 2004 and 2009. Area-restricted search patterns and dive behaviour were established from location data gathered by CTD satellite- relayed data loggers. At-sea movements of the seals demonstrated that >40% of the juvenile ele- phant seal population tagged use the Kerguelen Plateau during the austral winter. Search activity increased where temperature at 200 m depth was lower, when closer to the shelf break, and, to a lesser extent, where sea-surface height anomalies were higher. However, while this model explained the observed data (F1,242 = 88.23, p < 0.0001), bootstrap analysis revealed poor predic- tive capacity (r2 = 0.264). There appears to be potential overlap between the seals and commercial fishing operations in the region. This study may therefore support ecosystem-based fisheries man- agement of the region, with the aim of maintaining ecological integrity of the shelf. KEY WORDS: Diving behaviour · 3-dimensional utilisation · Shelf break · Temperature · Sea-surface height · Fisheries management Resale or republication not permitted without written consent of the publisher INTRODUCTION cally indicated by reduced transit speed and in - creased turning frequency within a given area and is Quantifying animal movement provides informa- often indicative of foraging activity (e.g. -
A Balanced Model of the Food Web of the Ross Sea, Antarctica
CCAMLR Science, Vol. 17 (2010): 1–31 A BALANCED MODEL OF THE FOOD WEB OF THE ROSS SEA, ANTARCTICA M.H. Pinkerton, J.M. Bradford-Grieve National Institute of Water and Atmospheric Research (NIWA) Ltd Private Bag 14901, Wellington 6241 New Zealand Email – [email protected] S.M. Hanchet NIWA Ltd PO Box 893, Nelson 7040 New Zealand Abstract A quantitative food web of the Ross Sea is presented here as a step towards investigating ecosystem effects of the fishery for Antarctic toothfishDissostichus ( mawsoni). The model consolidates quantitative information on trophic links across all the major biota of the Ross Sea and tests for data consistency. The model has 38 trophic groups and is balanced in terms of annual flows of organic carbon in an average recent year (1990–2000). The focus of the model is on the role of Antarctic toothfish in the food web which means that the model has greater taxonomic resolution towards the top of the food web than the base. A survey of the available literature and both published and unpublished data provided an initial set of parameters describing the annual average abundance, imports, exports, energetics (growth, reproduction, consumption) and trophic linkages (diets, key predators) for each model group. The relative level of uncertainty on these parameters was also estimated. This set of parameters was not self consistent, and a method is described to adjust the initial parameter set to give a balanced model, taking into account the estimates of parameter uncertainty and the large range of magnitude (>6 orders of magnitude) in trophic flows between groups. -
Microsatellite Markers for the Notothenioid Fish Lepidonotothen
Papetti et al. BMC Res Notes (2016) 9:238 DOI 10.1186/s13104-016-2039-x BMC Research Notes SHORT REPORT Open Access Microsatellite markers for the notothenioid fish Lepidonotothen nudifrons and two congeneric species Chiara Papetti1*, Lars Harms1, Jutta Jürgens1, Tina Sandersfeld1,2, Nils Koschnick1, Heidrun Sigrid Windisch1,3, Rainer Knust1, Hans‑Otto Pörtner1 and Magnus Lucassen1 Abstract Background: Loss of genetic variability due to environmental changes, limitation of gene flow between pools of individuals or putative selective pressure at specific markers, were previously documented for Antarctic notothenioid fish species. However, so far no studies were performed for the Gaudy notothen Lepidonotothen nudifrons. Starting from a species-specific spleen transcriptome library, we aimed at isolating polymorphic microsatellites (Type I; i.e. derived from coding sequences) suitable to quantify the genetic variability in this species, and additionally to assess the population genetic structure and demography in nototheniids. Results: We selected 43,269 transcripts resulting from a MiSeq sequencer run, out of which we developed 19 primer pairs for sequences containing microsatellite repeats. Sixteen loci were successfully amplified in L. nudifrons. Eleven microsatellites were polymorphic and allele numbers per locus ranged from 2 to 17. In addition, we amplified loci identified from L. nudifrons in two other congeneric species (L. squamifrons and L. larseni). Thirteen loci were highly transferable to the two congeneric species. Differences in polymorphism among species were detected. Conclusions: Starting from a transcriptome of a non-model organism, we were able to identify promising polymor‑ phic nuclear markers that are easily transferable to other closely related species. These markers can be a key instru‑ ment to monitor the genetic structure of the three Lepidonotothen species if genotyped in larger population samples. -
Buenos Aires Or Santiago
ANTARCTICA NEW! ANTARCTICA + PATAGONIA, ARGENTINA TO SOUTH GEORGIA GO DEEP ABOARD OUR POLAR FLEET SOLAR ECLIPSE PATH IN 2021 PLUS FREE AIR 2021-2023 VOYAGES | EXPEDITIONS.COM Hanusse Bay, Antarctica 66.56° S, 67.29° W Realizing that out here in pure wildness, curiosity is mutual. That’s the exhilaration of discovery. TABLE OF CONTENTS 2 Going Where Awesome Is 4 The Perfect Platform 8 Freedom to Explore 10 Our Expedition Team 12 Undersea Discoveries 16 National Geographic Photographers 18 Antarctica: The White Continent 20 Itinerary: Journey to Antarctica 22 Itinerary: Antarctica & Patagonia: Legendary Ice & Epic Fjords NEW 26 Antarctica, South Georgia & the Falklands 28 Itinerary: South Georgia & the Falklands 30 Itinerary: Antarctica, South Georgia & the Falklands 32 Itinerary: Wild Coasts of Argentina, South Georgia & the Falklands NEW 34 Epic Antarctica: The Peninsula to the Ross Sea & Beyond 36 Itinerary: Epic Antarctica 38 Explore More: Optional Extensions 40 Life Aboard 42 Dining Aboard 44 National Geographic Explorer 46 National Geographic Endurance/National Geographic Resolution 48 Offers, Terms & Conditions ICE FEVER: IT’S A THING 2 GOING WHERE AWESOME IS EDIFYING. EXHILARATING. AND DEEPLY MOVING. The Antarctic ice sheet is the most distinctive feature of Earth as seen from space—every astronaut’s account mentions it. And the ice is what makes every Antarctic explorer vow to return. There’s a whole glossary of ice words to learn—macro-scale terms like fast ice, leads, and growlers, to more granular terms like brash and bergy The single best whale encounter bits. Ice is visually stunning, and nearly kaleidoscopic in I’ve ever had. -
Food and Feeding Ecology of the Neritic-Slope Forager Black-Browed Albatross and Its Relationships with Commercial Fisheries in Kerguelen Waters
MARINE ECOLOGY PROGRESS SERIES Vol. 207: 183–199, 2000 Published November 22 Mar Ecol Prog Ser Food and feeding ecology of the neritic-slope forager black-browed albatross and its relationships with commercial fisheries in Kerguelen waters Yves Cherel*, Henri Weimerskirch, Colette Trouvé Centre d’Etudes Biologiques de Chizé, UPR 1934 du Centre National de la Recherche Scientifique, 79360 Villiers-en-Bois, France ABSTRACT: Food and feeding ecology of black-browed albatrosses Diomedea melanophrys rearing chicks was studied during 2 austral summers (1994 and 1995) at the Kerguelen Islands. Dietary analy- sis and satellite tracking were used to estimate potential interactions with commercial fisheries in the area. Fish comprised 73% by fresh mass of albatross diet; other significant food items were penguins (14%) and cephalopods (10%). Twenty-one species of fish (232 individuals) were identified and included mainly nototheniid and channichthyid species. The most important were Dissostichus elegi- noides (18.3% by reconstituted mass), Channichthys rhinoceratus (16.9%), Lepidonotothen squam- ifrons (11.6%), and to a lesser extent, Bathyraja sp. (4.5%) and Notothenia cyanobrancha (4.5%). The cephalopod diet was dominated by 3 taxa, the ommastrephid squids Todarodes sp. (7.6%) and Mar- tialia hyadesi (3.6%), and the octopus Benthoctopus thielei (2.4%). Satellite tracking indicated that during trips lasting 2 to 3 d, albatrosses foraged mainly over the outer shelf and inner shelf-break of the Kerguelen Archipelago. Birds moved to northern, eastern and southern waters, but never to the western Kerguelen shelf where there was a commercial longline fishery for D. eleginoides. Interac- tions with trawlers targetting D. -
Chapter 34: Australia, Oceania, and Antarctica Today
GeoJournal As you read this chapter, use your journal to log the key economic activities of Australia, Chapter Overview Visit the Glencoe World Oceania, and Antarctica. Note interesting Geography Web site at geography.glencoe.com details that illustrate the ways in which and click on Chapter Overviews—Chapter 34 to human activities and the region’s environ- preview information about the region today. ment are interrelated. Guide to Reading Living in Australia, Consider What You Know Oceania, and Environments in Australia, Oceania, and Antarctica range from tropical rain forests to icy wastelands. What Antarctica attractions or activities might draw people to visit or live in a region with such extreme differences in the physical environment? Reading Strategy A Geographic View Organizing Complete a web diagram similar to the one below by filling in Antarctic Diving the developing South Pacific countries that receive much-needed income There’s something special about from tourism. peering beneath the bottom of the world. When Antarctica’s summer diving season begins in September Developing Countries the sun has been largely absent for six months, and the water . has become as clear as any in the Read to Find Out world. Visibility is measured not in feet but in football fields. • How do people in Australia, New . Only here can you orbit an Zealand, and Oceania make their electric-blue iceberg while livings? being serenaded by the eerie View from under Antarctic ice • What role does trade play in trills of Weddell seals. the economies of South Pacific countries? —Norbert Wu, “Under Antarctic Ice,” National Geographic, February 1999 • What means of transportation and communications are used in the region? Terms to Know The wonders hidden under Antarctic ice are • station among the many attractions of Australia, Oceania, and Antarctica.