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Title: Corrigendum to "A closer look at regime shifts based on coastal observations along the eastern boundary of the North Pacific",
Description: , , ,
Author: Breaker
Date: 2008-01-01T00:00:00Z

Title: Southern Hemisphere humpback whales wintering off Central America: Insights from water temperature into the longest mammalian migration,
Description: We report on a wintering area off the Pacific coast of Central America for humpback whales (Megaptera novaeangliae) migrating from feeding areas off Antarctica. We document seven individuals, including a mother/calf pair, that made this migration (approx. 8300 km), the longest movement undertaken by any mammal. Whales were observed as far north as 11° N off Costa Rica, in an area also used by a boreal population during the opposite winter season, resulting in unique spatial overlap between Northern and Southern Hemisphere populations. The occurrence of such a northerly wintering area is coincident with the development of an equatorial tongue of cold water in the eastern South Pacific, a pattern that is repeated in the eastern South Atlantic. A survey of location and water temperature at the wintering areas worldwide indicates that they are found in warm waters (21.1-28.3°C), irrespective of latitude. We contend that while availability of suitable reproductive habitat in the wintering areas is important at the fine scale, water temperature influences whale distribution at the basin scale. Calf development in warm water may lead to larger adult size and increased reproductive success, a strategy that supports the energy conservation hypothesis as a reason for migration. © 2007 The Royal Society., Cited By (since 1996):53, Marine Mammals, Birds & Turtles, ,
Author: Rasmussen, Palacios, Calambokidis, Saborío, Dalla Rosa, Secchi, Steiger, Allen, Stone
Date: 2007-01-01T00:00:00Z

Title: Effect of the bat star Asterina miniata (Brandt) on recruitment of the giant kelp Macrocystis pyrifera C. Agardh,
Description: Cited By (since 1996):10, Ecology, Seaweeds, CODEN: JEMBA, The effect of the common bat star, Asterina miniata (Brandt) on recruitment of the giant kelp, Macrocystis pyrifera C. Agardh, was addressed through laboratory grazing experiments, a field experiment, and modeling of feeding behavior. In the laboratory, Asterina miniata significantly decreased the density of sporophytes that developed from 1-wk-old gametophytes as well as the percent cover of 2-, 6-, and 7-wk-old sporophytes. All grazed blades remaining at the end of these experiments subsequently died. Small scale variability in spore settlement and sporophyte development were also evident in the laboratory. Bat star density significantly affected short-term kelp recruitment during a large-scale field experiment. Simple modeling suggested that high densities of Asterina miniata could graze nearly 100% of the bottom over the 90-day experiment. However, visible recruitment was seen in less than 30 days, and over this time, 36% of the substratum was predicted to have remained ungrazed. Macrocystis pyrifera of 1 to 3 cm in length may thus obtain a refuge in size from bat star grazing through rapid growth. These results indicate this generalist grazer can affect giant kelp recruitment but that even under high grazing pressure numerous plants survive. Bat star grazing probably does not contribute to large-scale differences in adult plant density but may contribute to small-scale patterns of dispersion., ,
Author: Leonard
Date: 1994-01-01T00:00:00Z

Title: Primary production, new production and vertical flux in the eastern Pacific Ocean,
Description: The sinking of participate organic matter in the ocean links food webs beneath the euphotic zone to surface primary production and is an important pathway for the downward transport of many elements 1-3. The flux of particulate organic carbon (POC) is also an important parameter in the global carbon cycle and may be related to long-term changes in atmospheric CO 24,5. In 1980, Suess 6synthesized existing measurements from sediment trap studies into a model to predict the vertical flux of POC from depth (z) and primary production (PP)6. The Suess model has become the standard for evaluating vertical flux data 7, for estimating the annual flux of POC in the ocean 8and for parameterizing ocean carbon cycle models 4,5. We present here a new model of the vertical flux of POC and particulate organic nitrogen (PON) from a set of contemporaneous measurements of PP and fluxes made during the VERTEX (Vertical Transport and Exchange) programme in the north-east Pacific. The VERTEX model indicates that PP and vertical fluxes of POC and PON, in the oligotrophic ocean are greater than previously suggested. In addition, the vertical flux of PON from the photic zone represents a measure of the PP that is supported by new nitrogen (new production) 9,10. In the north-east Pacific, new production ranged from 13 to 25% of primary production and was positively related to total PP. © 2002 Nature Publishing Group., Cited By (since 1996):144, ,
Author: Pace, Knauer, Karl, Martin
Date: 1987-01-01T00:00:00Z

Title: Characterization of microsatellite loci in the European green crab (Carcinus maenas),
Description: Carcinus maenas (Decapoda: Portunidae) has proven a highly successful invasive marine species whose potential economic and ecological impacts are of great concern worldwide. Here, we characterize 14 polymorphic microsatellite loci in C. maenas and its sister species Carcinus aestuarii. These markers will prove useful for fine-scale genetic analyses of native and introduced populations, for assessment of the sources and routes of invasion and for evaluation of post-invasion population dynamics. © 2006 Blackwell Publishing Ltd., Cited By (since 1996):14, Invertebrates, CODEN: MENOC, ,
Author: Tepolt, Bagley, Geller, Blum
Date: 2006-01-01T00:00:00Z

Title: Temporal stability and origin of chemoclines in the deep hypersaline anoxic Urania basin
Description: Submarine brine lakes feature sharp and persistent concentration gradients between seawater and brine, though these should be smoothed out by free diffusion in open ocean settings. The anoxic Urania basin of the eastern Mediterranean contains an ultrasulfidic, hypersaline brine of Messinian origin above a thick layer of suspended sediments. With a dual modeling approach we reconstruct its contemporary stratification by geochemical solute transport fundamentals and show that thermal convection is required to maintain mixing in the brine and mud layer. The origin of the Urania basin stratification was dated to 1650 years B.P., which may be linked to a major earthquake in the region. The persistence of the chemoclines may be key to the development of diverse and specialized microbial communities. Ongoing thermal convection in the fluid mud layer may have important yet unresolved consequences for sedimentological and geochemical processes, also in similar environments. © 2015. American Geophysical Union. All Rights Reserved., Export Date: 19 February 2016, Article
Author: Goldhammer, Schwärzle, Aiello, Zabel
Date: 2015-01-01T00:00:00Z

Title: Modeling the upper ocean dynamics in the Subantarctic and Polar Frontal Zones in the Australian sector of the Southern Ocean,
Description: A one-dimensional (1-D) mixed layer model (the Chen scheme) was applied in the Subantarctic Zone (SAZ) and the Polar Frontal Zone (PFZ) to simulate the upper ocean dynamics. The model was forced with 4 years data of the heat fluxes, freshwater fluxes, and wind stresses from the National Centers for Environmental Prediction. In both the SAZ and PFZ, the 1-D model was capable of reproducing the amplitude of the seasonal sea surface temperature (SST) and the seasonality of the mixed layer depth (MLD). The shallowest MLD was found in January-February (20 m in the SAZ, 35 m in the PFZ), and the deepest MLD was found between August and October (600 m in the SAZ, 160 m in the PFZ). The summer MLD was shallower in the SAZ than in the PFZ due to the lower wind stress. However, the shallower winter MLD in the PFZ than in the SAZ was due to the strong stratification in the water below the mixed layer. In the SAZ, variability in the wind stress was the dominant term driving the fluctuation in MLD in the summer, but variability in the heat flux was the major factor controlling the timing of the deepening and shoaling of the mixed layer in the winter. In the PFZ both the variability in the wind stress and the heat flux dominated the variability of the MLD in both the summer and the winter. Copyright 2001 by the American Geophysical Union., Cited By (since 1996):8, , , Downloaded from: http://onlinelibrary.wiley.com/doi/10.1029/2000JC000357/pdf (9 June 2014).
Author: Wang, Matear
Date: 2001-01-01T00:00:00Z

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: Sediment-water exchange of total mercury and monomethyl mercury in the San Francisco Bay-Delta,
Description: Five field trips were conducted in the San Francisco Bay-Delta between May 2000 and October 2001 to investigate the sediment-water exchange of total mercury (Hg) and monomethyl mercury (MMHg). Solid-phase Hg averaged ∼1 nmol g -1 and did not show any variability with depth or time or among sites. In contrast, solid-phase MMHg showed considerable vertical, temporal, and spatial variability (0.4-66 pmol g -1), with the highest values occurring at a peat-rich environment in May 2001, suggesting that MMHg production was largely controlled by temporal factors and habitat type. In pore water, both Hg and MMHg concentrations were generally elevated near the sediment-water interface during warm months. Sediment-water exchange flux of MMHg, determined with benthic chamber deployments, ranged from -92 to 850 pmol m -2 d -1, with higher values occurring in May. In most cases, diffusional fluxes of Hg and MMHg, estimated with the use of interfacial concentration gradients, constituted only a minor portion of the measured fluxes, suggesting the importance of advective processes on sediment-water exchange. Surface-water transect and time series studies conducted in Franks Tract support the commonly held belief that wetland and marsh regions are major sources for MMHg within the Delta. The integrated sediment-water fluxes of Hg and MMHg in the study area were estimated to be 130 and 6 mmol d -1, respectively, and the benthic input was as important a source of Hg and MMHg as the riverine input within the Delta during low-flow months., Cited By (since 1996):63, Rocks and Cores, Oceanography, CODEN: LIOCA, ,
Author: Choe, Gill, Lehman, Han, Heim, Coale
Date: 2004-01-01T00:00:00Z

Title: A shark antibody heavy chain encoded by a nonsomatically rearranged VDJ is preferentially expressed in early development and is convergent with mammalian IgG
Description: In most vertebrate embryos and neonates studied to date unique antigen receptors (antibodies and T cell receptors) are expressed that possess a limited immune repertoire. We have isolated a subclass of IgM, IgM1gj, from the nurse shark Ginglymostoma cirratum that is preferentially expressed in neonates. The variable (V) region gene encoding the heavy (H) chain underwent V-D-J rearrangement in germ cells "germline-joined"). Such H chain V genes were discovered over 10 years ago in sharks but until now were not shown to be expressed at appreciable levels; we find expression of H1gj in primary and secondary lymphoid tissues early in life, but in adults only in primary lymphoid tissue, which is identified in this work as the epigonal organ. H1gj chain associates covalently with light (L) chains and is most similar in sequence to IgM H chains, but like mammalian IgG has three rather than the four IgM constant domains; deletion of the ancestral IgM C2 domain thus defines both IgG and IgM1gj. Because sharks are the members of the oldest vertebrate class known to possess antibodies, unique or specialized antibodies expressed early in ontogeny in sharks and other vertebrates were likely present at the inception of the adaptive immune system., Cited By (since 1996):41, CODEN: PNASA, Fish and Fisheries
Author: Rumfelt, Avila, Diaz, Bartl, McKinney, Flajnik
Date: 2001-01-01T00:00:00Z

Title: Dietary niche expansion of a kelp forest predator recovering from intense commercial exploitation
Description: Marine ecosystems are increasingly at risk from overexploitation and fisheries collapse. As managers implement recovery plans, shifts in species interactions may occur broadly with potential consequences for ecosystem structure and function. In kelp forests off San Nicolas Island, California, USA, we describe striking changes in size structure and life history traits (e.g., size at maturation and sex change) of a heavily fished, ecologically important predator, the California sheephead (Semicossyphus pulcher). These changes occurred in two phases: (1) after intense commercial fishery exploitation in the late 1990s and (2) following recovery in the late 2000s, nearly a decade after management intervention. Using gut contents and stable-isotope values of sheephead and their prey, we found evidence for a dietary niche expansion upon recovery of population size structure to include increased consumption of sea urchins and other mobile invertebrate grazers by larger sized fish. By examining historical diet data and a time series of benthic community composition, we conclude that changes in dietary niche breadth are more likely due to the recovery of size structure from fishing than major shifts in prey availability. Size-dependent predator-prey interactions may have ecosystem consequences and management measures that preserve or restore size structure, and therefore historical trophic roles of key predators, could be vital for maintaining kelp forest ecosystem health. © 2014 by the Ecological Society of America., Fish and Fisheries
Author: Hamilton, Newsome, Caselle

Title: Contamination of the deep-sea,
Description: Cited By (since 1996):17 Oceanography, CODEN: MPNBA, , ,
Author: Ballschmiter, Froescheis, Jarman, Caillet
Date: 1997-01-01T00:00:00Z

Title: Tidal and nontidal oscillations in Elkhorn Slough, CA,
Description: Elkhorn Slough is a shallow, tidally forced estuary that is directly connected to Monterey Bay. It is ebb-dominated and, due to continued erosion, the tidal prism has tripled over the past 40 years. Water level measurements at four locations are used to examine tidal and nontidal oscillations in Elkhorn Slough. The tidal response of Elkhorn Slough differs from that of Monterey Bay primarily due to the generation of a relatively large number of shallow-water tidal constituents that are due to tidal distortion caused by friction along the bottom and lateral boundaries, intertidal storage, and nonlinear advection. The shallow-water constituents range from 3 to almost 15 cycles per day (cpd) and include a rich variety of overtides and compound tides, whose amplitudes generally increase toward the head of the slough. The tidal harmonics are seasonally dependent, with lower amplitudes during the fall and winter and higher amplitudes in summer. The tidal constituents were examined using two types of spectral decomposition, the conventional power spectrum and the more recent Hilbert spectrum. Unlike the power spectrum, the Hilbert spectrum does not reveal any harmonic structure in the data. Energy associated with tidal distortion in this case appears to be broadly distributed across the spectral continuum. At least four nontidal oscillations occur in Elkhorn Slough with frequencies of 26.0, 39.7, 52.7, and 66.9 cpd. The Hilbert spectrum reveals maxima at 26, 39.7, and 66.9 cpd, but not at 52.7 cpd, suggesting that it is harmonically related to the oscillation at 26.0 cpd. The nontidal oscillations fall into the range of frequencies associated with the natural oscillations of Monterey Bay. However, evolutionary power spectra indicate that they appear to be permanent features of the system and thus are not necessarily consistent with seiche-like oscillations that are often transient and subject to damping. These oscillations could be caused by several factors including edge waves along the coast of Monterey Bay, long-period surface waves of atmospheric origin that enter the bay from offshore, or breaking internal waves in and around the Monterey Submarine Canyon. In conclusion, detailed hydrodynamic models are needed to provide a better understanding of how tidal harmonics are generated and preserved in Elkhorn Slough, and to determine the origin of the natural oscillations in Monterey Bay. © 2007 Coastal and Estuarine Research Federation., Cited By (since 1996):12, ,
Author: Breaker, Broenkow, Watson, Jo
Date: 2008-01-01T00:00:00Z

Title: Sedimentation in McMurdo Sound, Antarctica: A disturbance mechanism for benthic invertebrates,
Description: A slumping event that occurred on permanent transect lines from 12- to 30- m depth located at Arrival Heights, McMurdo Sound, Antarctica in 1993, provided an opportunity to examine the effects of sediment-mediated disturbance on the benthic invertebrate fauna. The disturbance had a particularly significant impact on the soft coral Alcyonium paessleri, which resulted in 84% colony mortality downslope from the slump site compared to an average annual mortality rate of 14% on control transects. In contrast, anchor ice at the same site accounted for removal of 5% of the population in 1992. Laboratory experiments with A. paessleri colonies under conditions of periodic sediment resuspension indicate that the soft corals are susceptible to this form of disturbance. Our observations suggest they are capable of shedding fine silt in the laboratory, which might ex-plain the presence of A. paessleri in soft-sediment sites around McMurdo Sound. However, scarring by larger gravel in laboratory assays was slow to heal and may account for much of the colony mortality we observed. Several invertebrate-barren rocky benthic regions in McMurdo Sound were suggestive of historical slumping events. Given the removal of the smaller grain size sediments from these areas - a typically slow process it appears these communities are slow to recover. The long-term effects of sedimentation on the benthic communities are unknown, but the impact on A. paessleri, one of the most common and fastest growing species, suggests this disturbance mechanism could lead to significant restructuring of these communities., Cited By (since 1996):13, Invertebrates, CODEN: POBID, ,
Author: Slattery, Bockus
Date: 1997-01-01T00:00:00Z

Title: Population biology of the intertidal kelp, Alaria marginata Postels and Ruprecht: A non-fugitive annual,
Description: Persistence of annual plant populations requires sufficient seeds and suitable habitat for development and growth each year. Competition with perennials may prevent within site persistence and result in "fugitive" annual populations. Comparisons have been made between the population biology of annual macroalgae and terrestrial plants, but demographic information necessary to make strong comparisons is lacking for most of these algae, and life history differences may make such comparisons questionable. We studied population dynamics of the kelp Alaria marginata to determine if it was an annual and, if so, how populations persisted. This kelp is the dominant macroalga on exposed mid to low rocky intertidal shores along the Big Sur coast of California. Experimental clearings at two sites were used to assess recruitment timing and survivorship. Sporophytes were collected monthly to determine growth and fecundity. Recruitment occurred in late winter to early spring, primarily on geniculate corallines and residual A. marginata holdfasts. Thinning was inversely related to density, and occurred during the February through July growing season as larger thalli rapidly increased in length (up to 1.4 m month-1) and formed a thick canopy. Sorus development was positively related to size, began as early as March, peaked in late August-October, and decreased as adults were removed by winter surf. Spore release was generally highest (108-109 spores individual-11 h-1) between October and January and associated with high water motion. Survivorship of sporophytes beyond one year was < 1%, showing the populations were annual. Field observations and experiments on effects of canopy clearing, season of clearing, and influence of substrate type on recruitment were done to assess how these annual populations persist. Massive spore production at the onset of fall storms, survival of microscopic stages for 3-4 months facilitated by microhabitat refuges, rapid growth, large size and rapid maturation of sporophytes contributed to persistence. Furthermore, the dense stands with thick canopies may suppress potential competitors via shading and abrasion. Rather than being a fugitive, this combination of growth and life history features enables A. marginata and perhaps other large, annual kelps to maintain perennial populations. © 2005 Elsevier B.V. All rights reserved., Cited By (since 1996):9, CODEN: JEMBA, ,
Author: McConnico, Foster
Date: 2005-01-01T00:00:00Z

Title: Particulate thallium fluxes in the northeast pacific,
Description: Particulate fluxes of thallium in the northeast Pacific exhibit pronounced spatial gradients, which range over four orders of magnitude (3 X 10-1 to 5.4 X 103 nmol m-2a-1) and show scavenging by both organic and inorganic processes. They are highly correlated (R=0.96) with POC fluxes, have have elevated rates in coastal upwelling waters, and decrease exponentially with depth. They also appear to be correlated with lateral fluxes of manganese (hydro)oxides off the continental shelf. These findings substantiate recent seawater measurements which indicate that metastable species of monovalent thallium are cycled through the marine biosphere as a potassium analogue, whereas thermodynamically stable trivalent thallium (TI (OH)3) is scavenged by ferromanganese (hydro)oxides. © 1989., Cited By (since 1996):11, CODEN: MRCHB, ,
Author: Flegal, Sanudo-Wilhelmy, Fitzwater
Date: 1989-01-01T00:00:00Z

Title: Food habits of the two-line eelpout (Bothrocara brunneum: Zoarcidae) at two deep-sea sites in the eastern North Pacific,
Description: Two-line eelpouts were collected from two deep-sea sites in the eastern North Pacific in order to study food habits. The diet of this species is low in diversity, consisting primarily of shrimp-like crustaceans and secondarily of small zoarcid fishes. Although significant differences in diet exist between the two study sites, it appears that two-line eelpouts have a narrow dietary breadth. Previous and concurrent surveys of the region indicate that there is a wide range of potential prey available to two-line eelpouts; however, the species appears to be using a narrow range of benthopelagic fauna, suggesting that it is capable of some degree of prey specialization., Cited By (since 1996):7, CODEN: DRORE, ,
Author: Ferry
Date: 1997-01-01T00:00:00Z

Title: The relationship between water motion and living rhodolith beds in the southwestern Gulf of California, Mexico,
Description: Free living, nodular aggregates of non-geniculate coralline algae (rhodoliths) have occurred since the Cenozoic in diverse marine environments around the world. Fossil rhodolith morphology and distribution have been widely used as paleoecological indicators, particularly of water motion. However, few studies have verified these relationships in living beds. The relationship between water motion and rhodolith movement was examined in three subtidal rhodolith beds off the southwestern coast of the Gulf of California, one dominated by wave action and two dominated by tidal currents. Field experiments and simultaneous video and current measurements taken during winter 1996 showed that rhodoliths in the shallow margins (4.5 m depths) of wave-dominated beds moved frequently due to threshold-level velocities from wind-propagated waves. Rhodoliths did not move in the middle and at deep margins of the bed due to attenuation of wave energy. Historical wind records and waveforcasting analysis indicate that shallow rhodolith movement is frequent only in the winter. In deep tidally dominated beds, maximum yearly tidal currents were not sufficient to move rhodoliths. Video and SCUBA surveys showed that bioturbation is an important mechanism for rhodolith movement in all beds. Rhodoliths in 12-m-deep tidally dominated beds and in the deep margins of wave-dominated beds appear to move only occasionally due to bioturbation and severe storms. Results imply that rhodolith morphology and distribution are dependent on a combination of factors. These factors, especially bioturbation, should be considered when using rhodoliths as paleoecological indicators., Cited By (since 1996):66, ,
Author: Marrack
Date: 1999-01-01T00:00:00Z

Title: First account of steller sea lion (Eumetopias jubatus) predation on a California sea lion (Zalophus californianus),
Description: Cited By (since 1996):4, CODEN: MMSCE, , ,
Author: Byrnes, Hood
Date: 1994-01-01T00:00:00Z

Title: Effects of zoospore aggregation and substrate rugosity on kelp recruitment success,
Description: Successful kelp recruitment is important for kelp population persistence and associated kelp forest communities. The proximity of settled kelp zoospores is a known requirement for successful kelp recruitment and proximity can be increased as zoospores aggregate. Substrate rugosity can also be an important factor affecting macroalgal settlement and recruitment in wave-swept areas, and may affect kelp recruitment by aggregating zoospores. In this study, kelp zoospores were cultured at different levels of small-scale aggregation and kelp recruitment was quantified. Sporophyte production significantly increased as zoospores became more aggregated indicating that processes that aggregate kelp zoospores have the potential to enhance kelp recruitment. A 13-month field experiment demonstrated differential kelp recruitment onto settlement plates that mimicked surface rugosities of two common rock types within Stillwater Cove, Carmel Bay in central California (Carmelo Formation sandstone and Santa Lucia granodiorite). Significantly more kelp recruited to molds mimicking granodiorite over the yearlong study (granodiorite = 2.7 recruits ± SE 0.50, sandstone = 1.2 recruits ± SE 0.51). There was a significant difference in recruitment between seasons and this variability was due to the fact that spring had the highest average number of kelp recruits per mold. However, the interaction between substrate and season was not significant. This study emphasizes the importance of kelp zoospore aggregation on kelp recruitment and demonstrates that small-scale rugosity affects kelp recruitment. © 2012 Phycological Society of America., Cited By (since 1996):1, Seaweeds, CODEN: JPYLA, ,
Author: Muth
Date: 2012-01-01T00:00:00Z

Title: A new species of Malthopsis (Lophiiformes: Ogcocephalidae) from the western Atlantic Ocean,
Description: A new species of Malthopsis is described from the western Atlantic Ocean, the first Malthopsis known from anywhere outside the Indo-western Pacific region except for Hawaii. Of 25 depth records, all were 275-475 m except one, which was 91 m., Cited By (since 1996):4, CODEN: BMRSA, , , Fish and Fisheries
Author: Bradbury
Date: 1998-01-01T00:00:00Z

Title: The effects of Cu on the adenylate energy charge of open ocean phytoplankton,
Description: The effects of short-term, acute Cu exposure (6 h) on the adenylate energy charge (EC A) of open-ocean phytoplankton populations (northeastern equatorial Pacific) were investigated. Energy charge remained at ̃0.77 over the range of Cu additions (0.025 - 5.μg l -1), even though 14C uptake and total adenylate levels (ATP + ADP + AMP) were reduced by as much as 60%. These findings suggest that EC A alone is not a sensitive indicator of acute sublethal metal effects on phytoplankton. © 1983 IRL Press Ltd., Cited By (since 1996):1, Oceanography, CODEN: JPLRD, ,
Author: Fitzwater, Knauer, Martin
Date: 1983-01-01T00:00:00Z

Title: Assessment of MERIS reflectance data as processed with SeaDAS over the European seas,
Description: The uncertainties associated with MERIS remote sensing reflectance (R RS) data derived from the SeaWiFS Data Analysis System (SeaDAS) are assessed with field observations. In agreement with the strategy applied for other sensors, a vicarious calibration is conducted using in situ data from the Marine Optical BuoY offshore Hawaii, and leads to vicarious adjustment factors departing from 1 by 0.2% to 1.6%. The three field data sets used for validation have been collected at fixed stations in the northern Adriatic Sea and the Baltic Sea, and in a variety of European waters in the Baltic, Black, Mediterranean and North Seas. Excluding Baltic waters, the mean absolute relative difference |Psi;| between satellite and field data is 10-14% for the spectral interval 490-560 nm, 16-18% at 443 nm, and 24-26%at413 nm. In the Baltic Sea, the |Psi;| values are much higher for the blue bands characterized by low RRS amplitudes, but similar or lower at 560 and 665 nm. For the three validation sets, the root-mean-square differences decrease from approximately 0.0013 sr -1 at 413 nm to 0.0002 sr -1 at 665 nm, and are found similar or lower than those obtained for SeaWiFS or MODIS-Aqua. As derived from SeaDAS, the RRS records associated with these three missions thus provide a multi-mission data stream of consistent accuracy. © 2011 Optical Society of America., Cited By (since 1996):4, Oceanography, ,
Author: Mélin, Zibordi, Berthon, Bailey, Franz, Voss, Flora, Grant
Date: 2011-01-01T00:00:00Z

Title: Characterizing source sink dynamics with genetic parentage assignments,
Description: Source-sink dynamics have been suggested to characterize the population structure of many species, but the prevalence of source-sink systems in nature is uncertain because of inherent challenges in estimating migration rates among populations. Migration rates are often difficult to estimate directly with demographic methods, and indirect genetic methods are subject to a variety of assumptions that are difficult to meet or to apply to evolutionary timescales. Furthermore, such methods cannot be rigorously applied to high-gene-flow species. Here, we employ genetic parentage assignments in conjunction with demographic simulations to infer the level of immigration into a putative sink population. We use individual-based demographic models to estimate expected distributions of parent-offspring dyads under competing sink and closed-population models. By comparing the actual number of parent-offspring dyads (identified from multilocus genetic profiles) in a random sample of individuals taken from a population to expectations under these two contrasting demographic models, it is possible to estimate the rate of immigration and test hypotheses related to the role of immigration on population processes on an ecological timescale. The difference in the expected number of parent-offspring dyads between the two population models was greatest when immigration into the sink population was high, indicating that unlike traditional population genetic inference models, the highest degree of statistical power is achieved for the approach presented here when migration rates are high. We used the proposed genetic parentage approach to demonstrate that a threatened population of Marbled Murrelets (Brachyramphus marmotus) appears to be supplemented by a low level of immigration (∼2-6% annually) from other populations. © 2008 by the Ecological Society of America., Cited By (since 1996):20, Marine Mammals, Birds & Turtles, CODEN: ECOLA, ,
Author: Peery, Beissinger, House, Bérubé, Hall, Sellas, Palsbøll
Date: 2008-01-01T00:00:00Z

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

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