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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: 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: 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: 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: 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

Title: Polar ecosystem dynamics: Recovery of communities from organic enrichment in McMurdo Sound, Antarctica,
Description: Community structure and diversity are influenced by patterns of disturbance and input of food. In Antarctica, the marine ecosystem undergoes highly seasonal changes in availability of light and in primary production. Near research stations, organic input from human activities can disturb the regular productivity regime with a consistent input of sewage. McMurdo Sound has both high-productivity and low-productivity habitats, thereby providing an ideal test bed for community recovery dynamics under polar conditions. We used experimental manipulations of the subtidal communities to test the hypotheses that (1) benthic communities respond differently to disturbance from organic enrichment versus burial and (2) community response also varies in areas with different natural patterns of food supply. Both in low- and high-food habitats, the strongest community response was to organic enrichment and resulted in dominance of typical organic-enrichment specialists. In habitats with highly seasonal productivity, community response was predictable and recovery was rapid. In habitats with low productivity, community variability was high and caging treatments suggested that inconsistencies were due to patchy impacts by scavengers. In areas normally subject to regular organic enrichment, either from primary production or from further up the food web (defecation by marine mammals), recovery of benthic communities takes only years even in a polar system. However, a low-productivity regime is as common in near shore habitats around the continent; under these conditions, recovery of benthic communities from disturbance is likely to be much slower and follow a variable ecological trajectory. © The Author 2010. Published y Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved., Cited By (since 1996):2, ,
Author: Kim, Hammerstom, Conlan, Thurber
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., Export Date: 19 October 2015
Author: Stark, Kim, Oliver
Date: 2014-01-01T00:00:00Z

Title: Antarctic research bases,
Description: Contemporary studies of chemical contamination in Antarctica commonly focus on remnants of historical local releases or long-range transport of legacy pollutants. To protect the continent's pristine status, the Antarctic Treaty's Protocol on Environmental Protection prohibits importation of persistent organic pollutants. However, some polybrominated diphenyl ether (PBDE) congeners exhibit similar properties. Many modern polymer-containing products, e.g., home/office furnishings and electronics, contain percent levels of flame retardant PBDEs. PBDE concentrations in indoor dust and wastewater sludge from the U.S. McMurdo and New Zealand-operated Scott Antarctic research bases were high. Levels tracked those in sludge and dust from their respective host countries. BDE-209, the major constituent in the commercial deca-PBDE product, was the dominant congener in sludge and dust, as well as aquatic sediments collected near the McMurdo wastewater outfall. The pattern and level of BDE-209 sediment concentrations, in conjunction with its limited environmental mobility, suggest inputs from local sources. PBDE concentrations in fish and invertebrates nearthe McMurdo outfall rivaled those in urbanized areas of North America and generally decreased with distance. The data indicate that reliance on wastewater maceration alone, as stipulated by the Protocol, may permit entry of substantial amounts of PBDEs and other chemicals to the Antarctic environment. © 2008 American Chemical Society., Cited By (since 1996):48, Antarctica, CODEN: ESTHA, ,
Author: Hale, Kim, Harvey, La Guardia, Mainor, Bush, Jacobs
Date: 2008-01-01T00:00:00Z

Title: The ARTEMIS under-ice AUV docking system
Description: The ARTEMIS docking system demonstrates autonomous docking capability applicable to robotic exploration of sub-ice oceans and sub-glacial lakes on planetary bodies, as well as here on Earth. In these applications, melted or drilled vertical access shafts restrict vehicle geometry as well as the in-water infrastructure that may be deployed. The ability of the vehicle to return reliably and precisely to the access point is critical for data return, battery charging, and/or vehicle recovery. This paper presents the mechanical, sensor, and software components that make up the ARTEMIS docking system, as well as results from field deployment of the system to McMurdo Sound, Antarctica in the austral spring of 2015. The mechanical design of the system allows the vehicle to approach the dock from any direction and to pitch up after docking for recovery through a vertical access shaft. It uses only a small volume of in-water equipment and may be deployed through a narrow vertical access shaft. The software of the system reduces position estimation error with a hierarchical combination of dead reckoning, acoustic aiding, and machine vision. The system provides critical operational robustness, enabling the vehicle to return autonomously and precisely to the access shaft and latch to the dock with no operator input.
Author: Kimball, Clark, Scully, Richmond, Flesher, Lindzey, Harman, Huffstutler, Lawrence, Lelievre, Moor, Pease, Siegel, Winslow, Blankenship, Doran, Kim, Schmidt, Stone

Title: Peripheral communities of the Eastern Lau Spreading Center and Valu Fa Ridge: community composition, temporal change and comparison to near-vent communities
Description: Western Pacific hydrothermal vents will soon be subjected to deep-sea mining and peripheral sites are considered the most practical targets. The limited information on community dynamics and temporal change in these communities makes it difficult to anticipate the impact of mining activities and recovery trajectories. We studied community composition of peripheral communities along a cline in hydrothermal chemistry on the Eastern Lau Spreading Center and Valu Fa Ridge (ELSC-VFR) and also studied patterns of temporal change. Peripheral communities located in the northern vent fields of the ELSC-VFR are significantly different from those in the southern vent fields. Higher abundances of zoanthids and anemones were found in northern peripheral sites and the symbiont-containing mussel Bathymodiolus brevior, brisingid seastars and polynoids were only present in the northern peripheral sites. By contrast, certain faunal groups were seen only in the southern peripheral sites, such as lollipop sponges, pycnogonids and ophiuroids. Taxonomic richness of the peripheral communities was similar to that of active vent communities, due to the presence of non-vent endemic species that balanced the absence of species found in areas of active venting. The communities present at waning active sites resemble those of peripheral sites, indicating that peripheral species can colonize previously active vent sites in addition to settling in the periphery of areas of venting. Growth and mortality were observed in a number of the normally slow-growing cladorhizid stick sponges, indicating that these animals may exhibit life history strategies in the vicinity of vents that differ from those previously recorded. A novel facultative association between polynoids and anemones is proposed based on their correlated distributions., Accepted
Author: Sen, Kim, Miller, Hovey, Hourdez, Luther, Fisher
Date: 2016-01-01T00:00:00Z

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