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Wilkie Johnston L, Manno C, Salinas CX. Assessment of plastic debris and biofouling in a specially protected area of the Antarctic Peninsula region. MARINE POLLUTION BULLETIN 2024; 207:116844. [PMID: 39163732 DOI: 10.1016/j.marpolbul.2024.116844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2024] [Revised: 08/07/2024] [Accepted: 08/09/2024] [Indexed: 08/22/2024]
Abstract
The aim of this paper is to characterize the plastic and to study a potential relationship between plastic debris characteristics and the presence of fouling biota in an Antarctic Specially Protected Area Robert Island, on the Antarctic peninsula region. A combination of lab-based sorting, advanced spectral analysis and general linear modelling was used to assess the abundance and type of plastic debris washed up on the shore. Observations recorded 730 debris items, with 85 % being plastic. Polystyrene (PS) and Polyethylene terephthalate (PET) were the dominant plastics (61 %). Biofouling was observed on 25 % of plastic debris, with debris complexity and degradation significantly increasing the likelihood of fouling occurring. There was no correlation found between biofouling type and plastic polymer type. Findings raise concerns that even with the highest level of environmental protection, an external marine-based source of pollution can intrude the coastal habitat, with uncertain consequences to local flora and fauna.
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Affiliation(s)
| | - Clara Manno
- British Antarctic Survey (BAS), Natural Environment Research Council, Cambridge CB3 0ET, UK
| | - Carla Ximena Salinas
- Instituto Antártico Chileno (INACH), Plaza Benjamín Muñoz Gamero 1055, Punta Arenas, Chile.
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2
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Gallagher KL, Selig GM, Cimino MA. Descriptions and patterns in opportunistic marine debris collected near Palmer Station, Antarctica. MARINE POLLUTION BULLETIN 2024; 199:115952. [PMID: 38142665 DOI: 10.1016/j.marpolbul.2023.115952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/04/2023] [Accepted: 12/15/2023] [Indexed: 12/26/2023]
Abstract
Observations of marine debris in Antarctica have been increasing; however, impacts, distributions, sources, and transport pathways of debris remain poorly understood. Here, we describe the spatial distribution, types, and potential origins of marine debris in 2022/2023 near Palmer Station, Antarctica. We opportunistically collected 135 pieces of marine debris with the majority of items found along shorelines (90 %), some found in/near seabird nests/colonies (7 %) and few on inland rocky terrain (3 %). Plastic and abandoned, lost, or discarded fishing gear dominated observed debris. Results suggest that wind and the Antarctic Coastal Current may be a major pathway for debris. This study is the first assessment of marine debris in this region and suggests that oceanography, weather patterns, and shoreline geomorphology could play a role in determining where debris will accumulate. Continued tracking of debris and development of structured surveys is important for understanding the impacts of human activities in a biological hotspot.
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Affiliation(s)
- Katherine L Gallagher
- Institute for Advanced Computational Sciences, Stony Brook University, 100 Nicolls Rd, Stony Brook, New York 11794, USA; School of Marine and Atmospheric Sciences, Stony Brook University, 100 Nicolls Rd, Stony Brook, New York 11794, USA.
| | - Gina M Selig
- Hawai'i Sea Grant Fellow to the National Science Foundation, Office of Polar Programs, Geosciences Directorate, 2415 Eisenhower Avenue Suite W7100, Alexandria, VA 22314 USA.
| | - Megan A Cimino
- Institute of Marine Sciences, University of California Santa Cruz, 1156 High St, Santa Cruz, California, 95064, USA.
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3
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Gurumoorthi K, Luis AJ. Recent trends on microplastics abundance and risk assessment in coastal Antarctica: Regional meta-analysis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 324:121385. [PMID: 36868550 DOI: 10.1016/j.envpol.2023.121385] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
We investigated sources, abundance and risk of microplastics (MPs) in water, sediments and biota around Antarctica. The concentration of MPs in Southern Ocean (SO) ranged from 0 to 0.56 items/m3 (mean = 0.01 items/m3) and 0-1.96 items/m3 (mean = 0.13 items/m3) in surface and sub-surface water. The distribution of fibers in water was 50%, sediments were 61%, and biota had 43%, which were followed by fragments in the water (42%), sediments (26%), and biota (28%). Shapes of film had lowest concentrations in water (2%), sediments 13%), and biota (3%). Ship traffic, drift of MPs by currents, and untreated waste water discharge contributed to the variety of MPs. The degree of pollution in all matrices was evaluated using the pollution load index (PLI), polymer hazard index (PHI), and potential ecological risk index (PERI). PLI at about 90.3% of locations were at category I followed by 5.9% at category II, 1.6% at category III, and 2.2% at category IV. Average PLI for water (3.14), sediments (6.6), and biota (2.72) had low pollution load (<10). Mean PHI for water, sediments, and biota showed hazards level V with a higher percentage of 84.6% (>1000) and 63.9% (PHI:0-1) in sediments and water, respectively. PERI for water showed 63.9% minor risk, and 36.1% extreme risk. Around 84.6% of sediments were at extreme risk, 7.7% faced minor risk, and 7.7% were at high risk. While 20% of marine organisms living in cold environments experienced minor risk, 20% were in high risk, and 60% were in extreme risk. Highest PERI was found in the water, sediments, and biota in Ross Sea, due to high hazardous polymer composition of polyvinylchloride (PVC) in the water and sediments due to human activity, particularly use of personnel care products and waste water discharge from research stations.
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Affiliation(s)
- K Gurumoorthi
- National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Goa, 403 804, India
| | - Alvarinho J Luis
- National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Goa, 403 804, India.
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4
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Swadling KM, Constable AJ, Fraser AD, Massom RA, Borup MD, Ghigliotti L, Granata A, Guglielmo L, Johnston NM, Kawaguchi S, Kennedy F, Kiko R, Koubbi P, Makabe R, Martin A, McMinn A, Moteki M, Pakhomov EA, Peeken I, Reimer J, Reid P, Ryan KG, Vacchi M, Virtue P, Weldrick CK, Wongpan P, Wotherspoon SJ. Biological responses to change in Antarctic sea ice habitats. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2022.1073823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Sea ice is a key habitat in the high latitude Southern Ocean and is predicted to change in its extent, thickness and duration in coming decades. The sea-ice cover is instrumental in mediating ocean–atmosphere exchanges and provides an important substrate for organisms from microbes and algae to predators. Antarctic krill, Euphausia superba, is reliant on sea ice during key phases of its life cycle, particularly during the larval stages, for food and refuge from their predators, while other small grazers, including copepods and amphipods, either live in the brine channel system or find food and shelter at the ice-water interface and in gaps between rafted ice blocks. Fish, such as the Antarctic silverfish Pleuragramma antarcticum, use platelet ice (loosely-formed frazil crystals) as an essential hatching and nursery ground. In this paper, we apply the framework of the Marine Ecosystem Assessment for the Southern Ocean (MEASO) to review current knowledge about relationships between sea ice and associated primary production and secondary consumers, their status and the drivers of sea-ice change in this ocean. We then use qualitative network modelling to explore possible responses of lower trophic level sea-ice biota to different perturbations, including warming air and ocean temperatures, increased storminess and reduced annual sea-ice duration. This modelling shows that pelagic algae, copepods, krill and fish are likely to decrease in response to warming temperatures and reduced sea-ice duration, while salp populations will likely increase under conditions of reduced sea-ice duration and increased number of days of >0°C. Differences in responses to these pressures between the five MEASO sectors were also explored. Greater impacts of environmental pressures on ice-related biota occurring presently were found for the West and East Pacific sectors (notably the Ross Sea and western Antarctic Peninsula), with likely flow-on effects to the wider ecosystem. All sectors are expected to be impacted over coming decades. Finally, we highlight priorities for future sea ice biological research to address knowledge gaps in this field.
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Koerich G, Fraser CI, Lee CK, Morgan FJ, Tonkin JD. Forecasting the future of life in Antarctica. Trends Ecol Evol 2023; 38:24-34. [PMID: 35934551 DOI: 10.1016/j.tree.2022.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 07/12/2022] [Accepted: 07/15/2022] [Indexed: 12/24/2022]
Abstract
Antarctic ecosystems are under increasing anthropogenic pressure, but efforts to predict the responses of Antarctic biodiversity to environmental change are hindered by considerable data challenges. Here, we illustrate how novel data capture technologies provide exciting opportunities to sample Antarctic biodiversity at wider spatiotemporal scales. Data integration frameworks, such as point process and hierarchical models, can mitigate weaknesses in individual data sets, improving confidence in their predictions. Increasing process knowledge in models is imperative to achieving improved forecasts of Antarctic biodiversity, which can be attained for data-limited species using hybrid modelling frameworks. Leveraging these state-of-the-art tools will help to overcome many of the data scarcity challenges presented by the remoteness of Antarctica, enabling more robust forecasts both near- and long-term.
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Affiliation(s)
- Gabrielle Koerich
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
| | - Ceridwen I Fraser
- Department of Marine Science, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Charles K Lee
- International Centre for Terrestrial Antarctic Research, School of Science, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand
| | - Fraser J Morgan
- Manaaki Whenua - Landcare Research, Auckland 1072, New Zealand; Te Pūnaha Matatini, Centre of Research Excellence in Complex Systems, Auckland, New Zealand
| | - Jonathan D Tonkin
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand; Te Pūnaha Matatini, Centre of Research Excellence in Complex Systems, Auckland, New Zealand; Bioprotection Aotearoa, Centre of Research Excellence, Canterbury, New Zealand.
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6
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Brooks CM, Ainley DG, Jacquet J, Chown SL, Pertierra LR, Francis E, Rogers A, Chavez-Molina V, Teh L, Sumaila UR. Protect global values of the Southern Ocean ecosystem. Science 2022; 378:477-479. [PMID: 36264826 DOI: 10.1126/science.add9480] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Climate change and fishing present dual threats.
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Affiliation(s)
- Cassandra M Brooks
- Department of Environmental Studies, University of Colorado Boulder, Boulder, CO, USA.
| | - David G Ainley
- H.T. Harvey & Associates Ecological Consultants, Los Gatos, CA, USA
| | - Jennifer Jacquet
- Department of Environmental Studies, New York University, New York, NY, USA
| | - Steven L Chown
- Securing Antarctica's Environmental Future, School of Biological Sciences, Monash University, Victoria, Australia
| | - Luis R Pertierra
- Department of Plant and Soil Sciences, University of Pretoria, Pretoria, South Africa
| | | | | | - Vasco Chavez-Molina
- Department of Environmental Studies, University of Colorado Boulder, Boulder, CO, USA.
| | - Louise Teh
- Institute for the Oceans and Fisheries and the School of Public Policy and Global Affairs, University of British Columbia, Vancouver, Canada
| | - U Rashid Sumaila
- Institute for the Oceans and Fisheries and the School of Public Policy and Global Affairs, University of British Columbia, Vancouver, Canada.,Institute for Environment and Development (LESTARI), National University of Malaysia, Selangor, Malaysia
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7
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Lozoya JP, Rodríguez M, Azcune G, Lacerot G, Pérez-Parada A, Lenzi J, Rossi F, de Mello FT. Stranded pellets in Fildes Peninsula (King George Island, Antarctica): New evidence of Southern Ocean connectivity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:155830. [PMID: 35561917 DOI: 10.1016/j.scitotenv.2022.155830] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Plastic and microplastic debris is transported by ocean currents over long distances, reaching remote areas, far from its original source. In Polar Regions, microplastics (MPs) can come from local activities or be transported from lower latitudes, with the former being the likely and major source. Although historically Antarctica was considered isolated from the global ocean, there is recent evidence of materials and organisms being transported in and out of the Southern Ocean, despite its multi-front structure. During the austral summer of 2019, beach surveys were conducted on the NW coast of the Fildes Peninsula (King George Island). The beach was characterised, and the first 2 cm of sediment from 5 quadrants (50 × 50 cm) along 100 m of the highest strandline were collected. Large microplastics (LMPs) and mesoplastics (MesoPs) were isolated, counted, measured, weighed and classified by shape. Polymer composition was analysed by FTIR and ageing estimated by Carbonyl Index. We found 293 items of LMPs (188 items) and MesoPs (105 items), with a total average density (±SD) of 234.4 ± 166 items m-2. Foams (130.4 ± 76.3), fragments (58.4 ± 56.0) and pellets (44.0 ± 50.5) were the most abundant shapes. The main polymers found were polystyrene, polypropylene, and polyethylene. We found pellets among the MesoPs, being the first record for beaches in Antarctica. The presence of these primary MPs south of 62°S not only alerts about their possible direct consequences on Antarctic ecosystems, but also gives empirical evidence for the passive entry of plastic debris from lower latitudes through cross-frontal exchanges, providing new evidence of a global connectivity of the Southern Ocean. Despite increasing research, knowledge of plastics dynamics and their impact in the Southern Ocean and Antarctica is still limited but certainly necessary.
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Affiliation(s)
- J P Lozoya
- Centro Universitario Regional del Este (CURE), Universidad de la República (UDELAR), Cachimba del Rey entre Bvar. Artigas y Av. Aparicio Saravia, 20000 Maldonado, Uruguay.
| | - M Rodríguez
- Centro Universitario Regional del Este (CURE), Universidad de la República (UDELAR), Ruta nacional N°9 intersección con ruta N°15, Rocha, Uruguay.
| | - G Azcune
- Centro Universitario Regional del Este (CURE), Universidad de la República (UDELAR), Ruta nacional N°9 intersección con ruta N°15, Rocha, Uruguay.
| | - G Lacerot
- Centro Universitario Regional del Este (CURE), Universidad de la República (UDELAR), Cachimba del Rey entre Bvar. Artigas y Av. Aparicio Saravia, 20000 Maldonado, Uruguay.
| | - A Pérez-Parada
- Centro Universitario Regional del Este (CURE), Universidad de la República (UDELAR), Ruta nacional N°9 intersección con ruta N°15, Rocha, Uruguay.
| | - J Lenzi
- Centro de Investigación y Conservación Marina (CICMAR), Uruguay
| | - F Rossi
- Centro Universitario Regional del Este (CURE), Universidad de la República (UDELAR), Cachimba del Rey entre Bvar. Artigas y Av. Aparicio Saravia, 20000 Maldonado, Uruguay
| | - F Teixeira de Mello
- Centro Universitario Regional del Este (CURE), Universidad de la República (UDELAR), Cachimba del Rey entre Bvar. Artigas y Av. Aparicio Saravia, 20000 Maldonado, Uruguay.
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8
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Constable AJ. Imperatives for integrated science and policy in managing greenhouse gas risks to the Southern Polar Region. GLOBAL CHANGE BIOLOGY 2022; 28:4489-4492. [PMID: 35575103 DOI: 10.1111/gcb.16219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 04/09/2022] [Indexed: 06/15/2023]
Abstract
The Southern Polar Region (Antarctica and the Southern Ocean) is threatened by climate change, and ocean warming and acidification. Reducing climate risks through direct human interventions in the region or through biological adaptation is not possible. Resilience of the region to global warming needs the establishment of climate refugia and science-based, climate-informed, ecosystem-based management, but long-term conservation will only be assured by global reduction in greenhouse gas emissions.
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Affiliation(s)
- Andrew J Constable
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
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Johnston NM, Murphy EJ, Atkinson A, Constable AJ, Cotté C, Cox M, Daly KL, Driscoll R, Flores H, Halfter S, Henschke N, Hill SL, Höfer J, Hunt BPV, Kawaguchi S, Lindsay D, Liszka C, Loeb V, Manno C, Meyer B, Pakhomov EA, Pinkerton MH, Reiss CS, Richerson K, Jr. WOS, Steinberg DK, Swadling KM, Tarling GA, Thorpe SE, Veytia D, Ward P, Weldrick CK, Yang G. Status, Change, and Futures of Zooplankton in the Southern Ocean. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2021.624692] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
In the Southern Ocean, several zooplankton taxonomic groups, euphausiids, copepods, salps and pteropods, are notable because of their biomass and abundance and their roles in maintaining food webs and ecosystem structure and function, including the provision of globally important ecosystem services. These groups are consumers of microbes, primary and secondary producers, and are prey for fishes, cephalopods, seabirds, and marine mammals. In providing the link between microbes, primary production, and higher trophic levels these taxa influence energy flows, biological production and biomass, biogeochemical cycles, carbon flux and food web interactions thereby modulating the structure and functioning of ecosystems. Additionally, Antarctic krill (Euphausia superba) and various fish species are harvested by international fisheries. Global and local drivers of change are expected to affect the dynamics of key zooplankton species, which may have potentially profound and wide-ranging implications for Southern Ocean ecosystems and the services they provide. Here we assess the current understanding of the dominant metazoan zooplankton within the Southern Ocean, including Antarctic krill and other key euphausiid, copepod, salp and pteropod species. We provide a systematic overview of observed and potential future responses of these taxa to a changing Southern Ocean and the functional relationships by which drivers may impact them. To support future ecosystem assessments and conservation and management strategies, we also identify priorities for Southern Ocean zooplankton research.
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Hwengwere K, Paramel Nair H, Hughes KA, Peck LS, Clark MS, Walker CA. Antimicrobial resistance in Antarctica: is it still a pristine environment? MICROBIOME 2022; 10:71. [PMID: 35524279 PMCID: PMC9072757 DOI: 10.1186/s40168-022-01250-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 02/23/2022] [Indexed: 05/19/2023]
Abstract
Although the rapid spread of antimicrobial resistance (AMR), particularly in relation to clinical settings, is causing concern in many regions of the globe, remote, extreme environments, such as Antarctica, are thought to be relatively free from the negative impact of human activities. In fact, Antarctica is often perceived as the last pristine continent on Earth. Such remote regions, which are assumed to have very low levels of AMR due to limited human activity, represent potential model environments to understand the mechanisms and interactions underpinning the early stages of evolution, de novo development, acquisition and transmission of AMR. Antarctica, with its defined zones of human colonisation (centred around scientific research stations) and large populations of migratory birds and animals, also has great potential with regard to mapping and understanding the spread of early-stage zoonotic interactions. However, to date, studies of AMR in Antarctica are limited. Here, we survey the current literature focussing on the following: i) Dissection of human-introduced AMR versus naturally occurring AMR, based on the premise that multiple drug resistance and resistance to synthetic antibiotics not yet found in nature are the results of human contamination ii) The potential role of endemic wildlife in AMR spread There is clear evidence for greater concentrations of AMR around research stations, and although data show reverse zoonosis of the characteristic human gut bacteria to endemic wildlife, AMR within birds and seals appears to be very low, albeit on limited samplings. Furthermore, areas where there is little, to no, human activity still appear to be free from anthropogenically introduced AMR. However, a comprehensive assessment of AMR levels in Antarctica is virtually impossible on current data due to the wide variation in reporting standards and methodologies used and poor geographical coverage. Thus, future studies should engage directly with policymakers to promote the implementation of continent-wide AMR reporting standards. The development of such standards alongside a centralised reporting system would provide baseline data to feedback directly into wastewater treatment policies for the Antarctic Treaty Area to help preserve this relatively pristine environment. Video Abstract.
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Affiliation(s)
- K. Hwengwere
- School of Life Sciences, Faculty of Science and Engineering, Anglia Ruskin University, East Road, Cambridge, CB1 1PT UK
- Marine Biology and Ecology Research Centre, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA UK
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET UK
| | - H. Paramel Nair
- School of Life Sciences, Faculty of Science and Engineering, Anglia Ruskin University, East Road, Cambridge, CB1 1PT UK
| | - K. A. Hughes
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET UK
| | - L. S. Peck
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET UK
| | - M. S. Clark
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET UK
| | - C. A. Walker
- School of Life Sciences, Faculty of Science and Engineering, Anglia Ruskin University, East Road, Cambridge, CB1 1PT UK
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Population characteristics of benthopelagic Gymnoscopelus nicholsi (Pisces: Myctophidae) on the continental shelf of South Georgia (Southern Ocean) during austral summer. Polar Biol 2022. [DOI: 10.1007/s00300-022-03033-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AbstractSouthern Ocean myctophid fish (Family Myctophidae) are an important conduit of energy through foodwebs and between the surface layers and mesopelagic depths. Species that reside in both pelagic and near-bottom environments of continental shelves, such as Gymnoscopelus nicholsi and Gymnoscopelus bolini, may also be important in benthopelagic coupling, although their ecology and role in such processes remain unresolved. Here, we examined inter-annual variation in the depth of occurrence, biomass and population dynamics of benthopelagic G. nicholsi on the South Georgia shelf (100–350 m) using bottom trawl data collected between 1987 and 2019. Gymnoscopelus nicholsi was a regular component of the local benthopelagic community, particularly northwest of South Georgia, but was patchily distributed. It appeared to enter a benthopelagic phase at ~ 3 years, with annual growth and recruitment of year classes between ~ 3 and 5 years. However, transition of cohorts into the benthopelagic zone was not annual. There was clear inter-annual variation in G. nicholsi biomass and depth of occurrence. Shallower depth of occurrence was significantly (P < 0.05) correlated with years of warmer summer sea surface temperatures, suggesting that inter-annual variation in local environmental conditions has an important influence on its migration behaviour and ecology. Our data also suggest that Antarctic krill is an important dietary component of the older G. nicholsi cohorts (~ 5 years) in the benthopelagic zone. We note that Gymnoscopelus bolini is rare in bottom trawl catches between 100 and 350 m, although Antarctic krill appears to dominate its diet from the available data. Our study provides important information on understudied myctophid species in a poorly investigated region of the water column that is relevant for Southern Ocean ecosystem studies, particularly in relation to understanding trophic connectivity between the pelagic and near-bottom realms.
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McCormack SA, Melbourne-Thomas J, Trebilco R, Griffith G, Hill SL, Hoover C, Johnston NM, Marina TI, Murphy EJ, Pakhomov EA, Pinkerton M, Plagányi É, Saravia LA, Subramaniam RC, Van de Putte AP, Constable AJ. Southern Ocean Food Web Modelling: Progress, Prognoses, and Future Priorities for Research and Policy Makers. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.624763] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Graphical AbstractGraphical summary of multiple aspects of Southern Ocean food web structure and function including alternative energy pathways through pelagic food webs, climate change and fisheries impacts and the importance of microbial networks and benthic systems.
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