Search results | Digital Commons of Moss Landing Marine Laboratories

Title: Stray light correction of the marine optical system,
Description: The Marine Optical System is a spectrograph-based sensor used on the Marine Optical Buoy for the vicarious calibration of ocean color satellite sensors. It is also deployed from ships in instruments used to develop bio-optical algorithms that relate the optical properties of the ocean to its biological content. In this work, an algorithm is applied to correct the response of the Marine Optical System for scattered, or improperly imaged, light in the system. The algorithm, based on the measured response of the system to a series of monochromatic excitation sources, reduces the effects of scattered light on the measured source by one to two orders of magnitude. Implications for the vicarious calibration of satellite ocean color sensors and the development of bio-optical algorithms are described. The algorithm is a one-dimensional point spread correction algorithm, generally applicable to nonimaging sensors, but can in principle be extended to higher dimensions for imaging systems. © 2009 American Meteorological Society., Cited By (since 1996):6, Oceanography, CODEN: JAOTE, , , Downloaded from: journals.ametsoc.org/doi/pdf/10.../2008JTECHO597.1 (16 June 2014).
Author: Feinholz, Flora, Yarbrough, Lykke, Brown, Johnson, Clark
Date: 2009-01-01T00:00:00Z

Title: The Marine Optical Buoy (MOBY) radiometric calibration and uncertainty budget for ocean color satellite sensor vicarious calibration,
Description: For the past decade, the Marine Optical Buoy (MOBY), an autonomous radiometric buoy stationed in the waters off Lanai, Hawaii, has been the primary in-water oceanic observatory for the vicarious calibration of U. S. satellite ocean color sensors, including the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and the Moderate Resolution Imaging Spectrometer (MODIS) instruments on the National Aeronautics and Space Administration's (NASA's) Terra and Aqua satellites. The MOBY vicarious calibration of these sensors supports international efforts to develop a global, multi-year time series of consistently calibrated ocean color data products. A critical component of the MOBY program is establishing radiometric traceability to the International System of Units (SI) through standards provided by the U. S. National Institute of Standards and Technology (NIST). A detailed uncertainty budget is a core component of traceable metrology. We present the MOBY uncertainty budget for up-welling radiance and discuss approaches in new instrumentation to reduce the uncertainties in in situ water-leaving radiance measurements., Cited By (since 1996):10, Oceanography, Art. No.: 67441M, CODEN: PSISD, ,
Author: Brown, Flora, Feinholz, Yarbrough, Houlihan, Peters, Yong, Mueller, Johnson, Clark
Date: 2007-01-01T00:00:00Z

Title: The feasibility of bomb radiocarbon analysis to support an age-at-length relationship for red abalone, Haliotis rufescens swainson in northern California,
Description: Cited By (since 1996):2, Downloaded from: www.bioone.org/doi/pdf/10.2983/0730-8000-27.5.1177 (3 July 2014)., , , ,
Author: Leaf, Andrews, Cailliet, Brown
Date: 2008-01-01T00:00:00Z

Title: Radiometric characterization and absolute calibration of the Marine Optical System (MOS) Bench Unit,
Description: The Marine Optical System (MOS) is a dual charge-coupled device (CCD)-based spectrograph system developed for in-water measurements of downwelling solar irradiance E d and upwelling radiance L u. These measurements are currently used in the calibration and validation of satellite ocean color measurement instruments such as the moderate resolution imaging spectroradiometer (MODIS) and the Sea-viewing Wide Field-of view Sensor (SeaWiFS). MOS was designed to be deployed from a ship for single measurements and also integrated into the Marine Optical Buoy (MOBY) for longer time series datasets. Measurements with the two spectrographs in the MOS systems can be compared in the spectral interval from about 580 to 630 nm. In this spectral range, they give different values for L u or E d at a common wavelength. To better understand the origin of this observation and the sources of uncertainty in the calibration of MOBY, an MOS bench unit was developed for detailed radiometric characterization and calibration measurements in a laboratory setting. In the work reported here, a novel calibration approach is described that uses a tunable laser-based, monochromatic, spatially uniform. Lambertian, large area integrating sphere source (ISS). Results are compared with those obtained by a conventional approach using a lamp-illuminated ISS. Differences in the MOS bench unit responsivity between the two calibration approaches were observed and attributed to stray light. A simple correction algorithm was developed for the lamp-illuminated ISS that greatly improves the agreement between the two techniques. Implications for water-leaving radiance measurements by MOS are discussed., Cited By (since 1996):2, CODEN: JAOTE, , , Downloaded from: journals.ametsoc.org/ (13 June 2014).
Author: Habauzit, Brown, Lykke, Johnson, Feinholz, Yarbrough, Clark
Date: 2003-01-01T00:00:00Z

Title: Biological response to iron fertilization in the eastern equatorial Pacific (IronEx II). I. Microplankton community abundances and biomass,
Description: During the IronEx II experiment in the eastern equatorial Pacific (May to June 1995), the response of the microplankton community to mesoscale iron fertilization was followed using a combination of marker-pigment, microscopical and flow cytometric techniques. Phytoplankton standing stock bloomed dramatically over a period of 6 d following 3 iron additions of 2 and 1 nM, respectively. Carbon biomass in the patch increased by a factor of 4, chlorophyll a by about a factor of 16 and diatoms by > 70-fold relative to contemporaneous levels in the ambient community. The bloom then plateaued sharply and remained at a more or less constant level for 4 d, despite the addition of more iron (1 nM) and physiological indices (low C:chl a ratio and elevated photochemical quantum efficiency) suggesting that the cells were healthy and growing rapidly. Relatively large pennate diatoms (Nitzschia spp., median length 20 to 24 μm) dominated the patch bloom, with smaller pennate species and centric diatoms declining in relative importance. Heterotrophic bacteria increased at a slow rate (0.08 d -1) for > 10 d during the experiment, as did heterotrophic nanoflagellates. There were also indications of enhanced cell size, cellular pigment content and possibly growth rates of small phytoplankton. Nonetheless, little difference was observed between the ambient community and the peak patch bloom with respect to the size composition of auto- and heterotrophic populations < 10 μm in cell size. The relative constancy of the smaller size fractions, the sharp curtailment of net growth of the bloom after 6 d, and > 3-fold increase in large heterotrophic dinoflagellates and ciliates suggest that protistan grazers may have played an active role in controlling the phytoplankton response to increased iron availability., , , ,
Author: Landry, Ondrusek, Tanner, Brown, Constantinou, Bidigare, Coale, Fitzwater
Date: 2000-01-01T00:00:00Z

Title: Initiation of long-term coupled microbiological, geochemical, and hydrological experimentation within the seafloor at North Pond, western flank of the Mid-Atlantic Ridge
Description: Integrated Ocean Drilling Program (IODP) Expedition 336 successfully initiated subseafloor observatory science at a young mid-ocean-ridge flank setting. All of the drilled sites are located in the North Pond region of the Atlantic Ocean (22°45'N, 46°05'W) in 4414-4483 m water depth. This area is known from previous ocean drilling and site survey investigations as a site of particularly vigorous circulation of seawater in permeable 8 Ma basaltic basement underlying a <300 m thick sedimentary pile. Understanding how this seawater circulation affects microbial and geochemical processes in the uppermost basement was the primary science objective of Expedition 336. Basement was cored and wireline-logged in Holes U1382A and U1383C. Upper oceanic crust in Hole U1382A, which is only 50 m west of Deep Sea Drilling Project (DSDP) Hole 395A, recovered 32 m of core between 110 and 210 meters below seafloor (mbsf). Core recovery in basement was 32%, yielding a number of volcanic flow units with distinct geochemical and petrographic characteristics. A unit of sedimentary breccia containing clasts of basalt, gabbroic rocks, and mantle peridotite was found intercalated between two volcanic flow units and was interpreted as a rock slide deposit. From Hole U1383C we recovered 50.3 m of core between 69.5 and 331.5 mbsf (19%). The basalts are aphyric to highly plagioclase-olivine-phyric tholeiites that fall on a liquid line of descent controlled by olivine fractionation. They are fresh to moderately altered, with clay minerals (saponite, nontronite, and celadonite), Fe oxyhydroxide, carbonate, and zeolite as secondary phases replacing glass and olivine to variable extents. In addition to traditional downhole logs, we also used a new logging tool for detecting in situ microbial life in ocean floor boreholes-the Deep Exploration Biosphere Investigative tool (DEBI-t). Sediment thickness was ∼90 m at Sites U1382 and U1384 and varied between 38 and 53 m at Site U1383. The sediments are predominantly nannofossil ooze with layers of coarse foraminiferal sand and occasional pebble-size clasts of basalt, serpentinite, gabbroic rocks, and bivalve debris. The bottommost meters of sections cored with the advanced piston corer feature brown clay. Extended core barrel coring at the sediment/basement interface recovered <1 m of brecciated basalt with micritic limestone. Sediments were intensely sampled for geochemical pore water analyses and microbiological work. In addition, high-resolution measurements of dissolved oxygen concentration were performed on the whole-round sediment cores. Major strides in ridge-flank studies have been made with subseafloor borehole observatories (CORKs) because they facilitate combined hydrological, geochemical, and microbiological studies and controlled experimentation in the subseafloor. During Expedition 336, two fully functional observatories were installed in two newly drilled holes (U1382A and U1383C) and an instrument and sampling string were placed in an existing hole (395A). Although the CORK wellhead in Hole 395A broke off and Hole U1383B was abandoned after a bit failure, these holes and installations are intended for future observatory science targets. The CORK observatory in Hole U1382A has a packer seal in the bottom of the casing and monitors/samples a single zone in uppermost oceanic crust extending from 90 to 210 mbsf. Hole U1383C was equipped with a three-level CORK observatory that spans a zone of thin basalt flows with intercalated limestone (∼70-146 mbsf), a zone of glassy, thin basaltic flows and hyaloclastites (146-200 mbsf), and a lowermost zone (∼200-331.5 mbsf) of more massive pillow flows with occasional hyaloclastites in the upper part.
Author: Edwards, Backert, Bach, Becker, Klaus, Griffin, Anderson, Haddad, Harigane, Campion, Hirayama, Mills, Hulme, Nakamura, Jørgensen, Orcutt, Insua, Park, Rennie, Salas, Rouxel, Wang, Russel, Wheat, Sakata, Brown, Magnusson, Ettlinger
Date: 2012-01-01T00:00:00Z

Title: Age validation of quillback rockfish (Sebastes maliger) using bomb radiocarbon,
Description: Rockfishes (Sebastes spp.) support one of the most economically important fisheries of the Pacific Northwest and it is essential for sustainable management that age estimation procedures be validated for these species. Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon (14C) signal in the ocean environment that scientists have identified as a useful tracer and chronological marker in natural systems. In this study, we first demonstrated that fewer samples are necessary for age validation using the bomb-generated 14C signal by emphasizing the utility of the time-specific marker created by the initial rise of bomb-14C. Second, the bomb-generated 14C signal retained in fish otoliths was used to validate the age and age estimation method of the quillback rockfish (Sebastes maliger) in the waters of southeast Alaska. Radiocarbon values from the first year's growth of quillback rockfish otoliths were plotted against estimated birth year to produce a 14C time series spanning 1950 to 1985. The initial rise in bomb-14C from prebomb levels (∼ -90‰) occurred in 1959 [±1 year] and 14C levels rose relatively rapidly to peak Δ14C values in 1967 (+105.4‰) and subsequently declined through the end of the time series in 1985 (+15.4‰). The agreement between the year of initial rise of 14C levels from the quillback rockfish time series and the chronology determined for the waters of southeast Alaska from yelloweye rockfish (S. ruberrimus) otoliths validated the aging method for the quillback rockfish. The concordance of the entire quillback rockfish 14C time series with the yelloweye rockfish time series demonstrated the effectiveness of this age validation technique, confirmed the longevity of the quillback rockfish up to a minimum of 43 years, and strongly confirms higher age estimates of up to 90 years., Cited By (since 1996):22, Fish and Fisheries, CODEN: FSYBA, ,
Author: Kerr, Andrews, Munk, Coale, Frantz, Cailliet, Brown
Date: 2005-01-01T00:00:00Z

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: 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: Application of bomb radiocarbon chronologies to shortfin mako (Isurus oxyrinchus) age validation,
Description: Age estimation is an issue for the shortfin mako, Isurus oxyrinchus, because of disagreement on vertebral band-pair deposition periodicity. In the 1950s-1960s, thermonuclear testing released large amounts of radiocarbon into the atmosphere, which diffused into the ocean through gas exchange. This influx created a time-specific marker that can be used in age validation. Annual band-pair deposition in the porbeagle, Lamna nasus, was validated in a previous study and indicated preliminary annual deposition in the shortfin mako, using four samples from one vertebra. In the present study, age estimates from 54 shortfin mako vertebrae collected in 1950-1984 ranged 1-31 years. Ageing error between readers was consistent, with 76% of the estimates ranging within 2 years. Twenty-one Δ14C values from eight shortfin mako vertebrae (collected in the western North Atlantic in 1963-1984) ranged -154.8‰ to 86.8‰. The resulting conformity with the Δ14C timeline for the porbeagle supported annual band-pair deposition in vertebrae of the shortfin mako. © 2006 Springer Science+Business Media, Inc., Cited By (since 1996):19, Fish and Fisheries, CODEN: EBFID, ,
Author: Ardizzone, Cailliet, Natanson, Andrews, Kerr, Brown
Date: 2006-01-01T00:00:00Z

Title: Holocene changes in the ecology of northern fur seals,
Description: The remains of northern fur seals (Callorhinus ursinus) are among the most abundant of pinniped elements recovered from mainland coastal archaeological sites in both California and Oregon. This is surprising as all contemporary northern fur seals breed exclusively on offshore islands, primarily at high latitudes, and the species is otherwise pelagic. The vulnerability of these animals to human predation suggests that either humans were foraging much further offshore than has been presumed or alternatively that the ecology of these animals has shifted during the late Holocene. We used isotopic and archaeofaunal analysis of the remains of pinnipeds from the middle to late Holocene of central and northern California to clarify the breeding and foraging behavior, and migration patterns of these ancient animals. The carbon and nitrogen isotope compositions of ancient northern fur seals reveal that these animals fed as far offshore as they do today, and that they remained at middle latitudes throughout the year. From an archaeological site at Moss Landing, California, we identified 16 skeletal elements from at least 12 very small northern fur seal pups. From another site near Mendocino, California, we identified the remains of at least 6 pups. We estimate the size and age of 5 of the young animals using sex-specific regressions of body length on the short dentary length derived from measurements of modern specimens. Our estimates indicate these ancient pups were substantially smaller, and therefore younger, than modern 3-month-old northern fur seal pups from similar latitudes and their nitrogen isotope compositions suggest they had not been weaned. As present-day northern fur seals do not leave their rookeries until they are at least 4 months old, we consider it highly unlikely that these ancient pups swam to these mainland locations from some distant island rookery. While there are numerous nearshore rocky outcrops along the Mendocino Coast, which may have supported small breeding colonies, the Moss Landing site is centered on a 40-km-long sandy beach, and is more than 120 km from what at the time were the nearest offshore islands. We conclude that northern fur seal adult females, subadults, and pups whose remains were recovered at the Moss Landing archaeological site must have been taken at a mainland rookery. Evidence that northern fur seals once bred on the mainland at this central California location suggests that the abundant remains of these animals at numerous other archaeological sites along the California coast also reflect the presence of nearby mainland rookeries. Based on the relative abundance of their remains in ancient human occupation sites and the widespread distribution of sites where their remains have been found, it appears that northern fur seals were once the predominant pinniped throughout a region where they now only rarely occur. Furthermore, their presence along the central and northern California coasts appears to have once severely limited the distribution of other pinnipeds, which are now common to the region., Cited By (since 1996):39, CODEN: OECOB, ,
Author: Burton, Snodgrass, Gifford-Gonzalez, Guilderson, Brown, Koch
Date: 2001-01-01T00:00:00Z

Title: Age validation of canary rockfish (Sebastes pinniger) using two independent otolith techniques,
Description: Canary rockfish (Sebastes pinniger) have long been an important part of recreational and commercial rockfish fishing from south-east Alaska to southern California, but localised stock abundances have declined considerably. Based on age estimates from otoliths and other structures, lifespan estimates vary from ∼20 years to over 80 years. For the purpose of monitoring stocks, age composition is routinely estimated by counting growth zones in otoliths; however, age estimation procedures and lifespan estimates remain largely unvalidated. Typical age validation techniques have limited application for canary rockfish because they are deep-dwelling and may be long-lived. In this study, the unaged otolith of the pair from fish aged at the Department of Fisheries and Oceans Canada was used in one of two age validation techniques: (1) lead-radium dating and (2) bomb radiocarbon (14C) dating. Age estimate accuracy and the validity of age estimation procedures were validated based on the results from each technique. Lead-radium dating proved successful in determining that a minimum estimate of lifespan was 53 years and provided support for age estimation procedures up to ∼50-60 years. These findings were further supported by Δ14C data, which indicated that a minimum estimate of lifespan was 44 ± 3 years. Both techniques validate, to differing degrees, age estimation procedures and provide support for inferring that canary rockfish can live more than 80 years. © CSIRO 2007., Cited By (since 1996):12, Fish and Fisheries, CODEN: AJMFA, ,
Author: Andrews, Kerr, Cailliet, Brown, Lundstrom, Stanley
Date: 2007-01-01T00:00:00Z

Title: Bomb radiocarbon and lead-radium disequilibria in otoliths of bocaccio rockfish (Sebastes paucispinis),
Description: Longevity estimates for the bocaccio rockfish (Sebastes paucispinis) using traditional techniques range from less than 20 years to approximately 50 years. Otoliths of bocaccio are difficult to age, and previous attempts to validate ages have been unsuccessful. Because otolith age suggests the bocaccio are reasonably long-lived, lead-radium dating was used in an attempt to independently age bocaccio otoliths. The measured 210Pb and 226Ra activities were among the lowest reported and resulted in poor radiometric age resolution; however, the break-and-burn technique clearly underestimated age in some cases with the longevity of the bocaccio being at least 31 years. To provide better age resolution, the bomb radiocarbon approach was applied to individual otoliths. Based on measured radiocarbon levels relative to a reference time-series, several specimens were aged at approximately 30-40 years. To evaluate these determinations, the remaining otolith of the pair was sectioned and aged blind. The result was an excellent fit to the reference time-series and a validation of the age estimates. The maximum age from growth zone counts was 37 ± 2 years, which is consistent with a reported maximum age of approximately 50 years. © CSIRO 2005., Cited By (since 1996):18, Fish and Fisheries, CODEN: AJMFA, ,
Author: Andrews, Burton, Kerr, Cailliet, Coale, Lundstrom, Brown
Date: 2005-01-01T00:00:00Z

Title: Southern Ocean Iron Enrichment Experiment,
Description: The availability of iron is known to exert a controlling influence on biological productivity in surface waters over large areas of the ocean and may have been an important factor in the variation of the concentration of atmospheric carbon dioxide over glacial cycles. The effect of iron in the Southern Ocean is particularly important because of its large area and abundant nitrate, yet iron-enhanced growth of phytoplankton may be differentially expressed between waters with high silicic acid in the south and low silicic acid in the north, where diatom growth may be limited by both silicic acid and iron. Two mesoscale experiments, designed to investigate the effects of iron enrichment in regions with high and low concentrations of silicic acid, were performed in the Southern Ocean. These experiments demonstrate iron's pivotal role in controlling carbon uptake and regulating atmospheric partial pressure of carbon dioxide., Cited By (since 1996):316, Oceanography, CODEN: SCIEA, ,
Author: Coale, Johnson, Chavez, Buesseler, Barber, Brzezinski, Cochlan, Millero, Falkowski, Bauer, Wanninkhof, Kudela, Altabet, Hales, Takahashi, Landry, Bidigare, Wang, Chase, Strutton, Friederich, Gorbunov, Lance, Hilting, Hiscock, Demarest, Hiscock, Sullivan, Tanner, Gordon, Hunter, Elrod, Fitzwater, Jones, Tozzi, Koblizek, Roberts, Herndon, Brewster, Ladizinsky, Smith, Cooper, Timothy, Brown, Selph, Sheridan, Twining, Johnson
Date: 2004-01-01T00:00:00Z

Title: Pelagic communities and sound scattering off Santa Barbara, California
Author: Ebeling, Cailliet, Ibara, DeWitt, Jr., Brown, Farquhar
Date: 1970-01-01T00:00:00Z

Title: Stray light correction algorithm for multichannel hyperspectral spectrographs,
Description: An algorithm is presented that corrects a multichannel fiber-coupled spectrograph for stray or scattered light within the system. The efficacy of the algorithm is evaluated based on a series of validation measurements of sources with different spectral distributions. This is the first application of a scattered-light correction algorithm to a multichannel hyperspectral spectrograph. The algorithm, based on characterization measurements using a tunable laser system, can be extended to correct for finite point-spread response in imaging systems. © 2012 Optical Society of America., Cited By (since 1996):1, Oceanography, CODEN: APOPA, ,
Author: Feinholz, Flora, Brown, Zong, Lykke, Yarbrough, Johnson, Clark
Date: 2012-01-01T00:00:00Z

Title: Radiocarbon in otoliths of yelloweye rockfish (Sebasfes ruberrimus): A reference time series for the coastal waters of southeast Alaska,
Description: Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon (14C) signal that has provided a useful tracer and chronological marker in oceanic systems and organisms. The bomb-generated 14C signal retained in fish otoliths can be used as a time-specific recorder of the 14C present in ambient seawater, making it a useful tool in age validation of fishes. The goal of this study was to determine 14C in otoliths of the age-validated yelloweye rockfish (Sebastes ruberrimus) to establish a reference time series for the coastal waters of southeast Alaska. Radiocarbon values from the first year's growth of 43 yelloweye rockfish otoliths plotted against estimated birth year produced a 14C time series (1940-1990) for these waters. The initial rise of 14C occurred in 1958 and 14C levels rose to peak values (60-70‰) between 1966 and 1971, with a subsequent declining trend through the end of the record in 1990 (-3.2‰). In addition, the 14C data confirmed the longevity of the yelloweye rockfish to a minimum of 44 years and strongly support higher age estimates. This 14C time series will be useful for the interpretation of 14C accreted in biological samples from these waters., Cited By (since 1996):24, CODEN: CJFSD, ,
Author: Kerr, Andrews, Frantz, Coale, Brown, Cailliet
Date: 2004-01-01T00:00:00Z

Title: Breaking with tradition: Redefining measures for diet description with a case study of the Aleutian skate Bathyraja aleutica (Gilbert 1896),
Description: Characterization of fish diets from stomach content analysis commonly involves the calculation of multiple relative measures of prey quantity (%N,%W,%FO), and their combination in the standardized Index of Relative Importance (%IRI). Examining the underlying structure of dietary data matrices reveals interdependencies among diet measures, and obviates the advantageous use of underused prey-specific measures to diet characterization. With these interdependencies clearly realized as formal mathematical expressions, we proceed to isolate algebraically, the inherent bias in %IRI, and provide a correction for it by substituting traditional measures with prey-specific measures. The resultant new index, the Prey-Specific Index of Relative Importance (%PSIRI), is introduced and recommended to replace %IRI for its demonstrated more balanced treatment of the relative measures of prey quantity, and less erroneous behavior across taxonomic levels of identified prey. As a case study, %PSIRI was used to examine the diet of the Aleutian skate Bathyraja aleutica from specimens collected from three ecoregions of the northern Gulf of Alaska (GOA) continental shelf during June-September 2005-2007. Aleutian skate were found to primarily consume the commonly abundant benthic crustaceans, northern pink shrimp Pandalus eous and Tanner crab Chionoecetes bairdi, and secondarily consume various teleost fishes. Multivariate variance partitioning by Redundancy Analysis revealed spatially driven differences in the diet to be as influential as skate size, sex, and depth of capture. Euphausiids and other mid-water prey in the diet were strongly associated with the Shelikof Strait region during 2007 that may be explained by atypical marine climate conditions during that year. © 2011 Springer Science+Business Media B.V., Cited By (since 1996):2, Fish and Fisheries, CODEN: EBFID, ,
Author: Brown, Bizzarro, Cailliet, Ebert
Date: 2012-01-01T00:00:00Z

Title: Age validation of quillback rockfish (Sebastes maliger) using bomb radiocarbon,
Description: Cited By (since 1996):26, , , ,
Author: Kerr, Andrews, Munk, Coale, Frantz, Cailliet, Brown
Date: 2005-01-01T00:00:00Z

Title: Investigations of Δ14C, δ13C, and δ15N in vertebrae of white shark (Carcharodon carcharias) from the eastern North Pacific Ocean,
Description: The white shark, Carcharodon carcharias, has a complex life history that is characterized by large scale movements and a highly variable diet. Estimates of age and growth for the white shark from the eastern North Pacific Ocean indicate they have a slow growth rate and a relatively high longevity. Age, growth, and longevity estimates useful for stock assessment and fishery models, however, require some form of validation. By counting vertebral growth band pairs, ages can be estimated, but because not all sharks deposit annual growth bands and many are not easily discernable, it is necessary to validate growth band periodicity with an independent method. Radiocarbon (14C) age validation uses the discrete 14C signal produced from thermonuclear testing in the 1950s and 1960s that is retained in skeletal structures as a time-specific marker. Growth band pairs in vertebrae, estimated as annual and spanning the 1930s to 1990s, were analyzed for Δ14C and stable carbon and nitrogen isotopes (δ13C and δ15N). The aim of this study was to evaluate the utility of 14C age validation for a wide-ranging species with a complex life history and to use stable isotope measurements in vertebrae as a means of resolving complexity introduced into the 14C chronology by ontogenetic shifts in diet and habitat. Stable isotopes provided useful trophic position information; however, validation of age estimates was confounded by what may have been some combination of the dietary source of carbon to the vertebrae, large-scale movement patterns, and steep 14C gradients with depth in the eastern North Pacific Ocean., Cited By (since 1996):28, CODEN: EBFID, ,
Author: Kerr, Andrews, Cailliet, Brown, Coale
Date: 2006-01-01T00:00:00Z

Title: Radiocarbon in otoliths of yelloweye rockfish (Sebasfes ruberrimus): A reference time series for the coastal waters of southeast Alaska,
Description: Cited By (since 1996):26, , , ,
Author: Kerr, Andrews, Frantz, Coale, Brown, Cailliet
Date: 2004-01-01T00:00:00Z

Title: Bomb radiocarbon and lead-radium disequilibria in otoliths of bocaccio rockfish (Sebastes paucispinis): A determination of age and longevity for a difficult-to-age fish,
Description: , , , ,
Author: Andrews, Burton, Kerr, Cailliet, Coale, Lundstrom, Brown

Title: The feasibility of bomb radiocarbon analysis to support an age-at-length relationship for red abalone, Haliotis rufescens Swainson in northern California,
Description: Analysis of bomb generated radiocarbon (14C) changes in a red abalone, Haliotis rufescens Swainson shell was used to evaluate age-at-length relationships derived from data from a previous multiyear, multisite tag-recapture study. Shell carbonate was extracted from four successive growth trajectory locations in a single shell with a maximum shell length of 251 mm. Extraction locations were based on Von Bertalanffy growth function (VBGF) predictions and chosen to span the initial rise of the 14C-bomb pulse that is known to have occurred in surface ocean waters during 1958 ±1 y in the northeast Pacific. The close temporal correspondence of the red abalone sample series to regional Δ14C records demonstrated the utility of the technique for validating age-at-length relationships for the red abalone. The findings provided support for a mean VBGF derived age of 32 y (range 30-33 y) for the specimen; however, the analysis of 14C data indicated that the specimen could be older., Cited By (since 1996):1, CODEN: JSHRD, , , Invertebrates
Author: Leaf, Andrews, Cailliet, Brown
Date: 2008-01-01T00:00:00Z

Title: Investigations of Δ14C, δ13C, and δ15N in vertebrae of white shark (Carcharodon carcharias) from the eastern North Pacific Ocean,
Description: Cited By (since 1996):35, , , ,
Author: Kerr, Andrews, Cailliet, Brown, Coale
Date: 2006-01-01T00:00:00Z

Title: Stray-light correction algorithm for spectrographs,
Description: In this paper, we describe an algorithm to correct a spectrograph's response for stray light. Two recursion relations are developed: one to correct the system response when measuring broad-band calibration sources, and a second to correct the response when measuring sources of unknown radiance. The algorithm requires a detailed understanding of the effect of stray light in the spectrograph on the instrument's response. Using tunable laser sources, a dual spectrograph instrument designed to measure the up-welling radiance in the ocean was characterized for stray light. A stray-light correction algorithm was developed, based on the results of these measurements. The instrument's response was corrected for stray light, and the effects on measured up-welling in-water radiance were evaluated., Cited By (since 1996):27, Oceanography, CODEN: MTRGA, ,
Author: Brown, Johnson, Feinholz, Yarbrough, Flora, Lykke, Clark
Date: 2003-01-01T00:00:00Z