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Title: Possible food caching and defence in the Weddell seal: Observations from McMurdo Sound, Antarctica,
Description: Cited By (since 1996):7, CODEN: ANTSE, , ,
Author: Kim, Conlan, Malone, Lewis
Date: 2005-01-01T00:00:00Z

Title: Temporal changes in marine environments in the Antarctic Peninsula area during the 1994/95 austral summer
Description: To reveal the temporal changes in Antarctic marine environments during the 1994/95 austral summer, oceanographic surveys were carried out in the Antarctic Peninsula area by Germany, Japan, Korea, and the USA. Five oceanographic stations at 15 nautical mile intervals were selected north of Elephant Island along 55°W; water temperature, salinity, nutrients, phytoplankton, krill and other zooplankton, and acoustic backscatter were sampled by similar sampling protocols. The transect was surveyed six times during the austral summer, from early December 1994 to late February 1995. The major findings from this time-series were : 1) The north/south position of the oceanic frontal zone north of Elephant Island along 55°W varied by 15 nautical miles; the northeasterly current associated with this front, determined by geostrophy, varied in strength depending on position of the front; 2) Most chl-a was concentrated in the upper 50m above or near the pycnocline. Surface chl-a concentrations ranged from 0.5mg/m^3 to >3.5mg/m^3. Peak chl-a (3.62mg/m^3) was found in the surface water during 18 February 1995. 3) Krill spawning during the 1994/95 season was early, extensive and apparently successful compared to previous years; and 4) Taxa other than krill may have contributed substantially to the observed acoustic backscattering.
Author: Kim, Siegel, Hewitt, Naganobu, Demer, Ichii, Kang, Kawaguchi, Loeb, Amos, Chung, Holm-Hansen, Lee, Silva, Stein

Title: Comparison of seastar (Asteroidea) fauna across island groups of the Scotia Arc,
Description: The Antarctic shelf fauna is isolated from other continental shelf faunas both physically by distance, and oceanographically by the Antarctic circumpolar current (ACC). To elucidate the relative importance of these two isolating mechanisms, we used the seastar fauna of the south-Atlantic sub-Antarctic islands to address the hypothesis that the ACC is dominant in controlling the distribution pattern of Antarctic fauna. We expected that seastar faunas from islands on the high latitude side of the ACC would show more similarities to each other than to faunas from islands on the low latitude side. The alternative isolation by distance model predicted that the island furthest from others would have the most unique fauna. For shelf-depth (<500 m) Asteroidea of the Scotia Arc region, assemblages were more similar between islands on each side of the ACC barrier than islands that were closer together, and this pattern was caused by differences in abundance of a few ubiquitous species. © 2006 Springer-Verlag., Cited By (since 1996):3 Invertebrates, ,
Author: Kim, Thurber
Date: 2007-01-01T00:00:00Z

Title: Broad-scale factors influencing the biodiversity of coastal benthic communities of the Ross Sea,
Description: Early ecological research in McMurdo Sound revealed local spatial gradients in community structure associated with variations in anchor ice disturbance, fast ice and snow cover, and the effects of predators. Research contrasting the east and west sides of McMurdo Sound has shown major differences in benthic communities, which have been attributed to oceanographic influences on the advection of water-column productivity and the frequency of fast ice break-out. Despite these regional and local differences, coastal benthic communities in McMurdo Sound show a high level of stability, and contain a variety of large and potentially very long-lived species. In Terra Nova Bay, about half way along the Victoria Land Coast of the western Ross Sea, the coastal benthic communities provide some insightful contrasts with those in McMurdo Sound. For example, the abundance and depth distribution of dominant species such as Sterechinus neumayeri and Adamussium colbecki are markedly different from McMurdo Sound. In both locations communities dominated by large sponges are most prolific in regions that are free from iceberg disturbance of the seabed. A recent assessment of northern Victoria Land coastal benthic communities, in conjunction with multibeam imagery of the seafloor, further highlights the importance of iceberg disturbance in structuring Antarctic benthic communities. A comparative synthesis of these coastal ecological studies enables us to generate hypotheses concerning the relative importance of different environmental drivers in structuring benthic communities. Overlain on the regular latitudinal shifts in physical factors such as light regime, are regional fluctuations that are controlled by atmospheric and oceanographic circulation patterns and coastal topography/bathymetry. Change in diversity along the western coast of the Ross Sea is predicted to be influenced by three main factors (1) ice disturbance (e.g., via anchor ice and advection of supercooled water or icebergs), (2) photosynthetically available radiation (affected by ice and snow cover and water clarity), (3) the locations of polynyas and advection of planktonic production and larvae. Interactions between these factors are expected to result in non-linear changes along the latitudinal gradient. While predictions generated from these hypotheses remain to be rigorously tested, they provide indications of how benthic communities may respond to changes in production, disturbance and the stability of coastal sea ice. © 2006 Elsevier Ltd. All rights reserved., Cited By (since 1996):28, Invertebrates, CODEN: DSROE, ,
Author: Thrush, Dayton, Cattaneo-Vietti, Chiantore, Cummings, Andrew, Hawes, Kim, Kvitek, Schwarz
Date: 2006-01-01T00:00:00Z

Title: The development of a new optical total suspended matter algorithm for the Chesapeake Bay,
Description: Sediment loading is one of the primary threats to the health of the Chesapeake Bay. We have developed a high resolution (250m) ocean color satellite tool to monitor sediment concentrations in the Bay. In situ optical and sediment sampling is used to develop a total suspended matter (TSM) algorithm for the Chesapeake Bay. The Coastal Optical Characterization Experiment (COCE) is part of an ongoing effort to optically characterize processes and to develop regional remote sensing ocean color algorithms in the coastal waters. The goal is to characterize sediment concentrations and to develop a tool to track plumes cascading down the Bay following heavy rainfall events. Background TSM concentrations in the Chesapeake Bay Watershed can also be characterized. The plumes can have potentially devastating effects on the Chesapeake Bay's fragile ecosystem by increasing nutrient loads, depositing sediments, and decreasing salinity and light levels. Sampling took place throughout 2006 to 2008 in the upper and mid portions of the Chesapeake Bay. Measurements of TSM, chlorophyll a (Chl), and hyperspectral optics were collected. The optical measurements included above water surface irradiance (E s(λ)), in-water downwelling irradiance (E d(λ)) and in-water upwelling radiance (L u(λ)). These optical data were used to analyze the performance and utility of the Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua Band 1 (645nm) for use as a TSM monitoring tool. From the optical measurements we have derived a 3rd order polynomial regression of TSM to normalized water-leaving radiance (r 2=0.79) to form an algorithm that quantitatively relates TSM to the MODIS 250m resolution band 1 (645nm). The algorithm performance was validated (a mean percent difference of -4.2%) against 270 total suspended solids samples collected by the Chesapeake Bay Program during routine water quality monitoring of the Chesapeake Bay environment. The TSM algorithm tool is then used to demonstrate monitoring of significant runoff events that occurred in June, 2006 and March, 2008. In addition, the utility of the Chesapeake Bay TSM product is demonstrated by describing regional and seasonal variations in sediment concentrations throughout the Chesapeake Bay for 2009. Mean concentrations ranged from 11.55mg/l in the upper Chesapeake Bay winter season to 6.37mg/l in the middle Chesapeake Bay spring season. These remote sensing tools can be valuable instruments in the detection and tracking of runoff events and background concentration for monitoring the health and recovery of the Chesapeake Bay. © 2012., Cited By (since 1996):7, CODEN: RSEEA, , , Oceanography
Author: Ondrusek, Stengel, Kinkade, Vogel, Keegstra, Hunter, Kim
Date: 2012-01-01T00:00:00Z

Title: Seastar response to organic enrichment in an oligotrophic polar habitat,
Description: The high Antarctic marine system, including McMurdo Sound, is food limited. Benthic scavengers, especially the seastar Odontaster validus, respond rapidly to sources of organic material, however, fecal material from the McMurdo Station sewage outfall is not consumed. Laboratory and field experiments showed that O. validus responded quickly (within hours) to organically enriched sediments, but that the presence of the anaerobic bacteria Beggiatoa spp. modified seastar behavior. In the lab, anoxic sediments, even more strongly than the presence of Beggiatoa, caused seastar avoidance. In the field, Beggiatoa caused seastar avoidance even of organically enriched sediments. The large mass of organic material remaining from pre-sewage treatment years at the McMurdo outfall is currently completely covered by a thick Beggiatoa microbial mat. O. validus and other megafaunal scavengers are abundant nearby but do not feed on the sewage organics that are covered by the microbes. The outfall deposit is thus likely to exist for a long period of time, undergoing slow anaerobic microbial degradation rather than rapid processing by megafaunal scavengers. This is an example of competition between constituents of the microbial and megafaunal communities and espouses the need for an ecosystem approach to ecology rather than community analysis within a limited size class (i.e. mega-, macro-, meio-, or micro-fauna). © 2007 Elsevier B.V. All rights reserved., Cited By (since 1996):10, Invertebrates, CODEN: JEMBA, ,
Author: Kim, Thurber, Hammerstrom, Conlan
Date: 2007-01-01T00:00:00Z

Title: Unusual coastal flood impacts in Salmon Valley, McMurdo Sound, Antarctica
Description: Large floods bringing significant sediments into the coastal oceans have not been observed in Antarctica. We report evidence of a large flood event depositing over 50 cm of sediment onto the nearshore benthic habitat at Salmon Bay, Antarctica, between 1990 and 2010. Besides direct observations of the sedimentation, the evidence involves a debris flow covering old tyre tracks from the early 1960s, as well as evidence of a considerable amount of sediment transported onto the Salmon Creek delta. We believe that the flood was sourced from the Salmon Glacier and possibly the smaller Blackwelder Glacier. Such floods will be more common in the future and it is important to better understand their ecological impacts with good monitoring programmes. © Antarctic Science Ltd 2016, Export Date: 13 May 2016, Article in Press
Author: Dayton, Hammerstrom, Jarrell, Kim, Nordhausen, Osborne, Thrush
Date: 2016-01-01T00:00:00Z

Title: Ocean optics protocols for satellite ocean color semsor validation, revision 4, Volume VI: Special topics in ocean protocols and appendices,
Description: , , ,
Author: Mueller, Clark, Kuwahara, Lazin, Brown, Fargion, Yarbrough, Feinholz, Flora, Broenkow, Kim, Johnson, Yuen, Strutton, Dickey, Abbott, Letelier, Lewis, McLean, Chavez, Barnard, Morrison, Subramaniam, Manov, Zheng, Harding Jr., Barnes, Lykke
Date: 2003-01-01T00:00:00Z

Title: Hydrothermal vent community zonation along environmental gradients at the Lau back-arc spreading center,
Description: The Lau back-arc spreading center exhibits gradients in hydrothermal vent habitat characteristics from north to south. Biological zonation within a few meters of vents has been described as temperature driven. We constructed georeferenced photomosaics of the seafloor out to tens of meters beyond vents to describe peripheral zonation and explore correlations between environmental conditions and the biological community. Cluster analysis separated northern sites from southern sites, corresponding to a break in substrate from basalt in the north to andesite in the south. Northern sites were dominated by anemones, and southern by sponges. A previous suggestion that dominants may be dependent on friability of the substrate was not supported; when visually distinguishable, individual species within taxa showed different patterns. Northern sites hosted proportionally more suspension feeding species. Sulfide that can support microbial food sources is at higher concentrations at these sites, though bathymetry that may enhance bottom currents is less rugged. Northern sites had higher diversity that may result from the overall northwards flow, which would generally permit easier dispersal downcurrent, though we observed no difference in dispersal strategies at different sites., Cited By (since 1996):1, CODEN: DRORE, ,
Author: Kim, Hammerstrom
Date: 2012-01-01T00:00:00Z

Title: Simultaneous measurement of up-welling spectral radiance using a fiber-coupled CCD spectrograph,
Description: Determination of the water-leaving spectral radiance using in-water instrumentation requires measurements of the upwelling spectral radiance (L u) at several depths. If these measurements are separated in time, changes in the measurement conditions result in increased variance in the results. A prototype simultaneous multi-track system was developed to assess the potential reduction in the Type A uncertainty in single set, normalized water-leaving radiance achievable if the data were acquired simultaneously. The prototype system employed a spectrograph and multi-track fiber-coupled CCD-detector; in situ in-water tests were performed with the prototype system fiber-coupled to a small buoy. The experiments demonstrate the utility of multi-channel simultaneous data acquisition for in-water measurement applications. An example of the potential impact for tracking abrupt responsivity changes in satellite ocean color sensors using these types of instruments as well as for the satellite vicarious calibration is given., Cited By (since 1996):1, Oceanography, Art. No.: 66800J, CODEN: PSISD, ,
Author: Yarbrough, Flora, Feinholz, Houlihan, Kim, Brown, Johnson, Voss, Clark
Date: 2007-01-01T00:00:00Z

Title: Development of the ROV SCINI and deployment in McMurdo Sound, Antarctica
Description: Remotely Operated Vehicles (ROVs) are powerful tools whose use has become common in many aquatic systems, for many purposes, from commercial to research applications. Polar regions, because of ice cover and harsh conditions, remain difficult locations for ROV work. This paper outlines the development of an ROV designed to facilitate exploration and scientific research under sea ice, giving easier access to largely unexplored regions of the seafloor. The ROV SCINI (Submersible Capable of under Ice Navigation and Imaging) was developed at Moss Landing Marine Laboratories and deployed in Antarctica for four field seasons, from 2007 to 2011. Ice provides a convenient deployment platform but commercially available ROVs require a large hole in the ice and much logistic support, which restricts their use in polar regions. Unlike other ROVs, SCINI has a slender torpedo shape (length: 1.4 m, diameter: 15 cm), which allows it to be deployed through a 20 cm hole in the ice. This small hole can be drilled by two people, using a handheld drill. The entire SCINI system and personnel (three or more persons) can fit in one helicopter, thus giving easy and quick access to remote sites. SCINI is a modular vehicle that can easily be modified or serviced in the field. It is also rugged and designed for harsh polar conditions. SCINI is equipped with two video cameras, scaling lasers, and lights. Its maximum depth capability is 300 m. A long baseline acoustic positioning system is used for navigation. SCINI is a highly manoeuvrable vehicle, better suited for flying transects over the seafloor than most ROVs. Engineering tests and scientific surveys were based out of McMurdo Station, Antarctica, and carried out at various sites within a 100 km radius. Knowledge gained from these deployments led to numerous modifications and improvements to the vehicle. This paper provides details on the vehicle's most recent configuration, including mechanical design, electrical design, software, and navigation system. Deployment methods, vehicle behaviour, and results of field testing are described. Four scientific surveys are also briefly described as examples. Copyright Journal of Ocean Technology 2011., Cited By (since 1996):3, Oceanography
Author: Cazenave, Zook, Carroll, Flagg, Kim
Date: 2011-01-01T00:00:00Z

Title: Towable instrumentation for use with a hand-deployed Remotely Operated Vehicle
Description: A new class of small, hand-deployable underwater vehicles is playing an increasingly important role in oceanographic science. Due to the small nature of these vehicles, traditional incorporation of oceanographic instrumentation into a vehicle's body can result in a device too massive or cumbersome to deployed by hand. In this paper, we present a towed instrument package, FATTI, as an alternative means of sensor integration for small underwater vehicles, specifically for the Remotely Operated Vehicle (ROV) SCINI. The flexibly attached instrument package is comprised of a 120 kHz scientific echosounder and fluorometer, and was deployed in the McMurdo Sound, Antarctica to map the spatial and temporal dynamics of krill, fishes, and phytoplankton. The tow package proved modular and fieldable, and performed over 100 dives during the 2012/13 and 2014/15 Antarctic field seasons.
Author: Barker, Kim, Saenz, Osborne, Daly

Title: New molluscan larval form: Brooding and development in a hydrothermal vent gastropod, Ifremeria nautilei (Provannidae),
Description: Despite extreme differences between some shallow and deep-sea habitats, the developmental modes and larval forms of deep-sea animals are typically similar to those of their shallow-water relatives. Here we report one of the first documented exceptions to this general rule. The hydrothermal vent snail Ifremeria nautilei displays two novel lifehistory traits: (1) an unusual uniformly ciliated larva that we here name Warén's larva, and (2) internal brood protection in a modified metapodial pedal gland. Warén's larva emerges from the internal brood pouch as a fully ciliated lecithotrophic larva with a unique external cuticle. The larvae swim with their posterior end forward and metamorphose into typical veliger larvae after 15 days at room temperature. Warén's larva is the only known example of a free-swimming pre-veliger larval stage in the higher gastropods and is the first new gastropod larval form to be described in more than 100 years. © 2010 Marine Biological Laboratory., Cited By (since 1996):2, CODEN: BIBUB, ,
Author: Reynolds, Watanabe, Strong, Sasaki, Uematsu, Miyake, Kojima, Suzuki, Fujikura, Kim, Young
Date: 2010-01-01T00:00:00Z

Title: Anthropogenic disturbance and biodiversity of marine benthic communities in Antarctica: A regional comparison
Description: The impacts of two Antarctic stations in different regions, on marine sediment macrofaunal communities were compared: McMurdo, a very large station in the Ross Sea; and Casey, a more typical small station in East Antarctica. Community structure and diversity were compared along a gradient of anthropogenic disturbance from heavily contaminated to uncontaminated locations. We examined some of the inherent problems in comparing data from unrelated studies, such as different sampling methods, spatial and temporal scales of sampling and taxonomic uncertainty. These issues generated specific biases which were taken into account when interpreting patterns. Control sites in the two regions had very different communities but both were dominated by crustaceans. Community responses to anthropogenic disturbance (sediment contamination by metals, oils and sewage) were also different. At McMurdo the proportion of crustaceans decreased in disturbed areas and polychaetes became dominant, whereas at Casey, crustaceans increased in response to disturbance, largely through an increase in amphipods. Despite differing overall community responses there were some common elements. Ostracods, cumaceans and echinoderms were sensitive to disturbance in both regions. Capitellid, dorvelleid and orbiniid polychaetes were indicative of disturbed sites. Amphipods, isopods and tanaids had different responses at each station. Biodiversity and taxonomic distinctness were significantly lower at disturbed locations in both regions. The size of the impact, however, was not related to the level of contamination, with a larger reduction in biodiversity at Casey, the smaller, less polluted station. The impacts of small stations, with low to moderate levels of contamination, can thus be as great as those of large or heavily contaminated stations. Regional broad scale environmental influences may be important in determining the composition of communities and thus their response to disturbance, but there are some generalizations regarding responses which will aid future management of stations. © 2014 Stark et al., Antarctica
Author: Stark, Kim, Oliver
Date: 2014-01-01T00:00:00Z

Title: Distribution and near-bottom transport of larvae and other plankton at hydrothermal vents,
Description: Distributions of larvae of benthic invertebrates and other planktonic organisms (holoplankton) were determined near hydrothermal vents along the East Pacific Rise (9°50'N) and combined with current meter records to estimate the extent and direction of transport in near-bottom flows. Diurnal tidal currents were strong enough to transport larvae substantial distances (up to 2 km) across the ridge axis during a single 12-h excursion. Potential longer-term transport in mean flows, however, appeared to be relatively slow (typically less than 1 km d-1). The proportion of larvae dispersing in near-bottom flows, as opposed to becoming entrained into the buoyant plume (and transported up out of the near-bottom environment) was estimated for a range of vent community sizes and black-smoker buoyancy fluxes, using a buoyant-plume entrainment model. These estimates suggested that larvae were most often transported in near-bottom currents, but that plume-level dispersal dominated for short periods of the tidal cycle (0.5-3 h) when the currents were slower than 1-2 cm s-1. The plume exit temperature also affects entrainment rate, so the proportion of larvae in each transport pathway (near-bottom flows and buoyant plumes) should vary substantially among vent habitats surrounding different temperature vents. The presence of certain holoplankton groups in diffuse vent flows, and their elevated abundances within the axial ridge valley, raises the possibility that these groups may be specifically associated with vent habitats., Cited By (since 1996):38, Invertebrates, CODEN: DSROE, ,
Author: Kim, Mullineaux
Date: 1998-01-01T00:00:00Z

Title: Benthic changes during 10 years of organic enrichment by McMurdo Station, Antarctica,
Description: A benthic habitat along the coast of McMurdo Station in the Ross Sea, Antarctica is enriched by sewage from the station and altered by hydrocarbons and heavy metals in an adjacent historic dumpsite. We report on 10 years of change in the benthic communities from 1988 to 1998 and compare enrichment effects at Australia's Casey Station, East Antarctica. Despite being 14 km apart, reference communities upcurrent and downcurrent of McMurdo Station remained closely similar over time, dominated in all years by a tube building polychaete, Spiophanes tcherniae. The community bordering McMurdo Station was generally a third as abundant as communities at the reference sites over the decade of sampling, although diversity was as high or higher, except in the most contaminated areas. In 1992, organic enrichment of the outfall community intensified and within the year, the opportunistic polychaetes Aphelochaeta sp., Ophryotrocha notialis, Capitella perarmata, and Leitoscoloplos kerguelensis became dominant. Since 1996, two of the three enriched communities have increased in resemblance to the reference communities. Given the observed responsiveness of the benthos to the outfall so far, further changes are anticipated within the year following implementation of sewage treatment in 2003. Organic enrichment by McMurdo Station has had a greater impact on benthic community structure than at Australia's Casey Station. © 2004 Elsevier Ltd. All rights reserved., Cited By (since 1996):37, CODEN: MPNBA, ,
Author: Conlan, Kim, Lenihan, Oliver
Date: 2004-01-01T00:00:00Z

Title: Recruitment, Growth and Mortality of an Antarctic Hexactinellid Sponge, Anoxycalyx joubini
Description: Polar ecosystems are sensitive to climate forcing, and we often lack baselines to evaluate changes. Here we report a nearly 50-year study in which a sudden shift in the population dynamics of an ecologically important, structure-forming hexactinellid sponge, Anoxycalyx joubini was observed. This is the largest Antarctic sponge, with individuals growing over two meters tall. In order to investigate life history characteristics of Antarctic marine invertebrates, artificial substrata were deployed at a number of sites in the southern portion of the Ross Sea between 1967 and 1975. Over a 22-year period, no growth or settlement was recorded for A. joubini on these substrata; however, in 2004 and 2010, A. joubini was observed to have settled and grown to large sizes on some but not all artificial substrata. This single settlement and growth event correlates with a region-wide shift in phytoplankton productivity driven by the calving of a massive iceberg. We also report almost complete mortality of large sponges followed over 40 years. Given our warming global climate, similar system-wide changes are expected in the future. © 2013 Dayton et al., Cited By (since 1996):4, Art. No.: e56939, Downloaded from: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0056939 (16 June 2014).
Author: Dayton, Kim, Jarrell, Oliver, Hammerstrom, Fisher, O'Connor, Barber, Robilliard, Barry, Thurber, Conlan
Date: 2013-01-01T00:00:00Z

Title: Surprising episodic recruitment and growth of Antarctic sponges: Implications for ecological resilience
Description: Sponges are the most conspicuous component of the Antarctic benthic ecosystem, a system under stress both from climate change and fishing activities. Observations over four decades are compiled and reveal extremely episodic sponge recruitment and growth. Recruitment occurred under different oceanographic conditions on both sides of McMurdo Sound. Most of the sponges appear to have recruited in the late 1990s–2000. Observations from 2000 to 2010 follow thirty years of relative stasis with very little sponge recruitment or growth followed by a general pattern of recruitment by some forty species of sponges. That there was almost no recruitment observed on natural substrata emphasizes the contrast between potential and realized recruitment. This unique data set was derived from a region noted for physical stasis, but the episodic ecological phenomena highlight the importance of rare events. Against a background of intermittent food resources and the low metabolic costs of stasis, understanding the causes of irregular larval supply, dispersal processes, recruitment success and survivorship becomes critical to predicting ecosystem dynamics and resilience in response to increasing environmental change. Our time-series emphasizes that long-term data collection is essential for meaningful forecasts about environmental change in the unique benthic ecosystems of the Antarctic shelf.
Author: Dayton, Jarrell, Kim, Thrush, Hammerstrom, Slattery, Parnell

Title: Fishing for data in the Ross Sea,
Description: Cited By (since 1996):5, CODEN: SCIEA, , ,
Author: Blight, Ainley, Ackley, Ballard, Ballerini, Brownell Jr., Cheng, Chiantore, Costa, Coulter, Dayton, Devries, Dunbar, Earle, Eastman, Emslie, Evans, Garrott, Kim, Kooyman, Lescroël, Lizotte, Massaro, Olmastroni, Ponganis, Russell, Siniff, Smith Jr., Stewart, Stirling, Willis, Wilson, Woehler
Date: 2010-01-01T00:00:00Z

Title: Hexabromocyclododecane flame retardant in Antarctica: Research stations as sources
Description: Historical persistent organic pollutants (POPs) are banned from Antarctica under international treaty; but contemporary-use POPs can enter as additives within polymer and textile products. Over their useful lives these products may release additives in-situ. Indeed, we observed 226 and 109 ng/g dry weight (dw) of the total concentrations of α-, β- and γ-hexabromocyclododecane (HBCD) in indoor dust from McMurdo Station (U.S.) and Scott Station (New Zealand), respectively. Sewage sludge collected from wastewater treatment facilities at these stations exhibited ΣHBCD of 45 and 69 ng/g dw, respectively. Contaminants originally within the bases may exit to the local outdoor environment via wastewaters. Near McMurdo, maximum ΣHBCD levels in surficial marine sediments and aquatic biota (invertebrates and fish) were 2350 ng/g (total organic carbon basis) and 554 ng/g lipid weight, respectively. Levels declined with distance from McMurdo. Our results illustrate that Antarctic research stations serve as local HBCD sources to the pristine Antarctic environment. © 2015 Elsevier Ltd. All rights reserved., Export Date: 28 September 2015
Author: Chen, Hale, La Guardia, Luellen, Kim, Geisz
Date: 2015-01-01T00:00:00Z

Title: Swarming benthic crustaceans in the Bering and Chukchi seas and their relation to geographic patterns in gray whale feeding,
Description: Swarms differed in their geographic extent, local biomass, and life stages of swarming individuals and thus in their availability to feeding Eschrichtius robustus. Immature amphipods apparently swarmed for dispersal, whereas cumaceans probably swarmed for mating. All life stages of the hyperbenthic mysids occurred above the sea floor. Although the geographic spread of mysid swarms and shrimp communities was much greater than for the amphipod and cumacean swarms, the latter swarmed in denser patches to produce higher local biomass. Crustacean swarms are important in describing the geographic patterns of gray whale feeding from the Chukchi Sea to Baja California. The primary feeding ground is in the S Chukchi Sea and especially the N Bering Sea, where gray whales suck infaunal amphipods from fine sand. The primary feeding ground is divided into a relatively deep zone (>20 m), where tube-dwelling ampeliscid amphipods are the major prey, and a shallow zone (<20 m), where burrowing pontoporeid amphipods dominate. The secondary feeding ground is in the S Bering Sea along the E Alaska Peninsula and adjacent Alaskan mainland where shrimp and mysids are the major prey. -from Authors, Cited By (since 1996):16, Invertebrates, Marine Mammals, Birds & Turtles, ,
Author: Kim, Oliver
Date: 1989-01-01T00:00:00Z

Title: Nesting behavior of the icefish Chaenocephalus aceratus at Bouvetøya Island, Southern Ocean,
Description: We describe in situ observations on nesting by the Scotia Sea (or blackfin) icefish Chaenocephalus aceratus (Lönnberg) that constitute the first substantive evidence of egg brooding and parental care by species of the family Channichthyidae. At Boutetoya Island six fish, all apparently male, were observed guarding egg nests at depths of 141-148 m during an ROV deployment. Eggs were laid as aggregated, round masses (∼20-25 cm diameter) in shallow, circular depressions (~1-m diameter, ∼20-cm depth) that were probably excavated by the parent(s) to protect the nests. The fish guardians remained tenaciously in contact with the eggs despite disturbances caused by the ROV, reacting to this threat with stress and defense behaviors. Because brooding fishes are more susceptible to the population impacts from trawl fisheries, we argue that this life history should be kept in mind in designing management schemes. © Springer-Verlag 2005., Cited By (since 1996):18, CODEN: POBID, ,
Author: Detrich III, Jones, Kim, North, Thurber, Vacchi
Date: 2005-01-01T00:00:00Z

Title: Variation in the biomass density and demography of Antarctic krill in the vicinity of the South Shetland Islands during the 1999/2000 austral summer,
Description: Vessels from Japan, Peru, and the USA conducted four sequential surveys designed to estimate the biomass density and demography of Antarctic krill in the vicinity of the South Shetland Islands between late December 1999 and early March 2000. The surveys were conducted during the same austral summer as the CCAMLR 2000 Survey in the Scotia Sea (Watkins et al., Deep-Sea Research, II, this issue [doi: 10.1016/j.dsr2.2004.06.010]), and the data were analyzed in a similar manner. Biomass densities were not significantly different between the surveys and averaged 49 g m -2. Maps of krill biomass indicate three areas of consistently high density: one near the eastern end of Elephant Island, one mid-way between Elephant Island and King George Island, and one near Cape Shirreff on the north side of Livingston Island. The areas of highest krill density appeared to move closer to the shelf break as the season progressed. This apparent movement was accompanied by a change in the demographic structure of the population, with smaller krill absent and a larger proportion of sexually mature animals present in late summer., Cited By (since 1996):8, CODEN: DSROE, Antarctica, ,
Author: Hewitt, Kim, Naganobu, Gutierrez, Kang, Takao, Quinones, Lee, Shin, Kawaguchi, Emery, Demer, Loeb
Date: 2004-01-01T00:00:00Z

Title: Variation in marine benthic community composition allows discrimination of multiple stressors,
Description: Predicting how communities respond to multiple, potentially interacting chemical stressors is inherently difficult because community structure and dynamics, the chemical properties of contaminants, and biological-chemical interactions vary with environmental conditions. Using a field experiment conducted in Antarctica, we tested whether 3 phyla of benthic soft-sediment marine invertebrates - annelids, arthropods, and echinoderms - respond differently to 2 common forms of contamination, organic enrichment and toxic contamination. Based on life history strategies and physiological tolerances to contaminants, we hypothesized that the principal responses of the 3 phyla would be: (1) enhanced abundance of annelids in organically enrichment sediments and (2) decreased abundance of arthropods and echinoderms in toxic metal contamination. Sediment treatments were established in the field experiment with an orthogonal combination of 3 levels of total organic carbon (TOC; 0, 1, and 2% by weight) and copper (Cu; 0, 100, and 500 μg Cu g-1 sediment), and colonization patterns were observed after 1 yr. Densities of annelids (mainly polychaetes) increased with TOC across all levels of Cu. Arthropods and echinoderms decreased with Cu, but responded variably to TOC, based largely on differences in habitat preferences exhibited by epifaunal and infaunal species. Small subsurface arthropod species (amphipods, isopods, cumaceans, and ostracods) decreased in high organic loading, due to induction of and exposure to hypoxia and hydrogen sulfide, but large surface deposit-feeding echinoderms (asteroids and echinoids) responded positively to increased carbon food supply. We present a predictive model based on assessment of benthic community structure conducted at the taxonomic level of phyla that could be used to link cause and effect for multiple chemical stressors in marine ecosystems., Cited By (since 1996):36, CODEN: MESED, Antarctica, ,
Author: Lenihan, Peterson, Kim, Conlan, Fairey, McDonald, Grabowski, Oliver
Date: 2003-01-01T00:00:00Z

Title: High species density patterns in macrofaunal invertebrate communities in the marine benthos,
Description: Species density of macrofaunal invertebrates living in marine soft sediments was highest at the shelf-slope break (100-150m) in Monterey Bay (449 m-2). There were 337 species m-2 in the mid-shelf mud zone (80 m). There were fewer species along the slope: 205 m-2 from the lower slope (950-2000 m) and 335 m-2 on the upper slope (250-750 m). Species density was highest inside the bay (328-446 m-2) compared to outside (336-339 m-2), when examining samples at selected water depths (60-1000 m). There was little difference in local species density from 1 km of shoreline compared to regional species density along 1000 km of shoreline at both shelf and slope depths. The highest species densities worldwide in the literature are recorded along the Carolina slope in the Atlantic Ocean, where peak species density (436/0.81 m2) at 800 m and values at the largest sample areas are similar to those on the Monterey Bay shelf. We speculate that the highest species densities occur where ocean water exchanges energy with shoaling topography at the continental margin, bringing more food to the benthos -- areas such as the very productive waters in the upwelling system of Monterey Bay., Cited By (since 1996):1, ,
Author: Oliver, Hammerstrom, McPhee-Shaw, Slattery, Oakden, Kim, Hartwell
Date: 2011-01-01T00:00:00Z

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