Search results

Title: The behaviour of iron and other trace elements during the IronEx-I and PlumEx experiments in the Equatorial Pacific,
Description: Dissolved (< 0.4 μm) and particulate (0.4-5 μm and > 5 μm, leachable and refractory) trace elements were measured during the IronEx I and PlumEx experiments in October and November 1993 near the Galapagos Islands. Iron was measured in the enriched patch and at control stations over a 9 day period following fertilization. The dissolved iron was initially depleted at a rate that gave an iron half-life of 28-40 h. The loss rate gradually decreased, and dissolved iron concentrations did not decrease below about 0.25 nmol kg-1 throughout the experiment. These results were most consistent with a kinetic model that was second order in iron concentration for the scavenging removal of each iron fraction. Other trace elements measured did not change significantly either in concentration or partitioning during the IronEx I experiment. Biological production tracked iron concentrations over time, which suggests that productivity within the fertilized patch was regulated by the availability of iron. The PlumEx study consisted primarily of two transects, a meridional course to the east of the Galapagos Islands and a zonal section to the west. Surface dissolved iron was very low at all stations except those near the Galapagos Islands. Sections of trace metal and other properties distinctly confirm the upwelling of the Equatorial Undercurrent as it intersects the islands. This upwelling has a great effect on the surface distributions of the trace metals on the west side of the islands. Productivity within the mixed layer of this region is highly correlated with iron and nitrate. West of the islands highest productivity is found at stations with the highest iron. North of the Equatorial front, in nitrate-depleted waters, elevated iron concentrations do not enhance productivity., Cited By (since 1996):58, Oceanography, CODEN: DSROE, ,
Author: Gordon, Johnson, Coale
Date: 1998-01-01T00:00:00Z

Title: Characterizing dispersal patterns in a threatened seabird with limited genetic structure,
Description: Genetic assignment methods provide an appealing approach for characterizing dispersal patterns on ecological time scales, but require sufficient genetic differentiation to accurately identify migrants and a large enough sample size of migrants to, for example, compare dispersal between sexes or age classes. We demonstrate that assignment methods can be rigorously used to characterize dispersal patterns in a marbled murrelet (Brachyramphus marmoratus) population from central California that numbers approximately 600 individuals and is only moderately differentiated (FST∼ 0.03) from larger populations to the north. We used coalescent simulations to select a significance level that resulted in a low and approximately equal expected number of type I and II errors and then used this significance level to identify a population of origin for 589 individuals genotyped at 13 microsatellite loci. The proportion of migrants in central California was greatest during winter when 83% of individuals were classified as migrants compared to lower proportions during the breeding (6%) and post-breeding (8%) seasons. Dispersal was also biased toward young and female individuals, as is typical in birds. Migrants were rarely members of parent-offspring pairs, suggesting that they contributed few young to the central California population. A greater number of migrants than expected under equilibrium conditions, a lack of individuals with mixed ancestry, and a small number of potential source populations (two), likely allowed us to use assignment methods to rigorously characterize dispersal patterns for a population that was larger and less differentiated than typically thought required for the identification of migrants. © 2009 Blackwell Publishing Ltd., Cited By (since 1996):11, Marine Mammals, Birds & Turtles, CODEN: MOECE, ,
Author: Hall, Palsbøll, Beissinger, Harvey, Bérubé, Raphael, Nelson, Golightly, McFarlane-Tranquilla, Newman, Peery
Date: 2009-01-01T00:00:00Z

Title: Dr. Michael Neushul,
Description: , , ,
Author: Reed, Norris, Foster
Date: 1994-01-01T00:00:00Z

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: Tectonic and glacial related seafloor geomorphology as possible demersal shelf rockfish habitat surrogates-Examples along the Alaskan convergent transform plate boundary,
Description: Seafloor geology plays a major role in habitat formation and can be used to remotely identify key habitats for some commercially important fish species. We have used a combination of side-scan sonar mosaics, multibeam bathymetry, and backscatter data, and in situ observations and video from the submersible Delta to investigate marine benthic habitats in the Eastern Gulf of Alaska. The intent of this paper is to review the results of previous marine benthic habitat mapping efforts completed by us along the transform plate boundary of Alaska and to present new information that show how volcanic, plutonic, and glacial submarine geomorphology can be used to identify potentially important discrete habitat areas. Demersal shelf rockfish, a seven-species management complex of nearshore rockfish, including yellow-eye rockfish (Sebastes ruberrimus), are found in rugged and highly rugose geomorphologic features. Eroded volcanic edifices, lava fields, and a pit crater, as well as a small shutterridge, deformed and differentially eroded sedimentary bedrock, and highly fractured and faulted plutonic rock outcrops are features that attract adult rockfish. Volcanic edifices that lie along the leaky (magma-conducting) Fairweather transform fault system intercept ocean currents, in turn producing upward eddies that bring nutrients to species residing on the features. We show that geologic processes such as fault deformation, volcanism, and glaciation are critical to the development of Essential Fish Habitats (EFH) for demersal shelf rockfish. Our work is the first attempt to determine a common geologic link between desperate commercial fishing areas in SE Alaska, USA, and to suggest how tectonic and glacial processes, including sea level rise and transgression, can be used to identify seafloor geologic characteristics as surrogates for marine groundfish habitats. © 2010 Elsevier Ltd., Cited By (since 1996):2, Ecology, Fish and Fisheries, CODEN: CSHRD, ,
Author: Greene, O'Connell, Brylinsky
Date: 2011-01-01T00:00:00Z

Title: What sharks can tell us about the evolution of MHC genes,
Description: Similarity in structural features would argue that sharks possess class I, class IIA and class IIB genes, coding for classical peptide-presenting molecules, as well as non-classical class I genes. Some aspects of shark major histocompatibility complex genes are similar to teleost genes and others are similar to tetrapod genes. Shark class I genes form a monophyletic group, as also seen for tetrapods, but the classical and nonclassical genes form two orthologous clades, as seen for teleosts. Teleost class I genes arose independently at least four different times with the nonclassical genes of ray-finned fishes and all the shark and lobe-finned fish class I genes forming 1 clade. The ray-finned fish classical class I genes arose separately. In phylogenetic trees of class II α2 and β2 domains, the shark and tetrapod genes cluster more closely than the teleost genes and, unlike the teleost sequences, the class II α1 domains of sharks and tetrapods lack cysteines. On the other hand, both shark and teleost genes display sequence motifs in the antigen-binding cleft that have persisted over very long time periods. The similarities may reflect common selective pressures on species in aqueous environments while differences may be due to different evolutionary rates., Cited By (since 1996):19, CODEN: IMRED, ,
Author: Bartl
Date: 1998-01-01T00:00:00Z

Title: The flux of iron from continental shelf sediments,
Description: The flux of dissolved iron from sediments to the water column was measured with flux chambers along the California coast over a five-year period. High fluxes were observed from sediments on the continental shelf. The measured fluxes were an average of 75 times larger than flux values derived from pore-water iron gradients. The iron flux was significantly correlated with the oxidation of organic matter, which allows an extrapolation to the global shelf. The input from shelf sediments is at least as significant as the global input of dissolved iron from aerosols, which has been presumed to be the dominant external iron source. Evidence of this input is seen 100's of kilometers offshore where it can enable the high productivity of broad coastal regions seen in satellite images. Copyright 2004 by the American Geophysical Union., Cited By (since 1996):125, Oceanography, CODEN: GPRLA, ,
Author: Elrod, Berelson, Coale, Johnson
Date: 2004-01-01T00:00:00Z

Title: Deepwater habitat and fish resources associated with the Big Creek Marine Ecological Reserve,
Description: Big Creek Marine Ecological Reserve (BCER), located off the central California coast, has been closed to fishing since January 1994. We used side scan sonar and an occupied submersible to collect baseline information on species-habitat relationships, density, and species and size composition of fish inside and outside BCER. Forty-three dives were made in the fall of 1997 and 1998, at depths of 20-250 m. From 142 video transects, we identified over 70,000 fish from 82 taxa, including 36 species of rockfish. About 93% of the 25,159 fish inside BCER were rockfishes representing at least 20 species. Young-of-the-year rockfishes dominated rock outcrops in 20-90 m depth inside and outside BCER. Four distinct fish assemblages were associated with (1) fine, smooth sediment in deep water; (2) bedrock with uneven surface in deep water; (3) sand waves and shell hash in shallow water; and (4) boulders and organic habitats on rock in shallow water. There were no significant differences in fish density among locations (inside and outside BCER) and depths or between years. Density was significantly higher in high-relief rock habitat than in low-relief soft and mixed sediments, regardless of location. There were no consistent patterns of larger fish inside compared to outside the protected area. We recommend development of a monitoring program to continue these surveys after increased time of protection and with increased assessment effort in the appropriate habitats of economically valuable species. In addition, extending the boundaries of BCER seaward would protect habitats and fish in water depths greater than 100 m., Cited By (since 1996):18, , , Downloaded from: http://calcofi.org/publications/ccreports.html (05 June 14).
Author: Yoklavich, Cailliet, Starr, Lea, De Marignac, Greene, Field
Date: 2002-01-01T00:00:00Z

Title: Settlement, growth and reproduction of benthic algae within Macrocystis forests in California,
Description: , , ,
Author: Harger, Coon, Foster, Neushul, Woessner
Date: 1981-01-01T00:00:00Z

Title: Erratum to Functional significance of intramandibular bending in Poeciliid fishes,
Description: Fish and Fisheries, CODEN: EBFID, , ,
Author: Gibb, Ferry-Graham, Hernandez, Romasco, Blanton
Date: 2008-01-01T00:00:00Z

Title: The validity of using morphological characteristics as predictors of age in the kelp, Pterygophora californica (Laminariales, Phaeophyta),
Description: Previous studies have used stipe ring counts to estimate the age of several species in the Laminariales. Although this method is widely accepted, it has rarely been validated. To test the validity of aging Pterygophora californica by counting rings formed in the stipe, we sampled plants of known age between 1.0 and 4.4 yr old and plants with a calculated age of 12 yr. For a given cohort, the number of complete rings closely approximated the known age in years. indicating ring counts are a reliable method for estimating the age structure of P califomica populations. However, ring counts from individual plants of known age can vary by ± 2 yr (95 % CI), and among readers counting the same plants by ± 1 yr (95 % CI). Single plants, there fore, could not be reliably aged by ring counts Linear relationships between 2 morphometric measures (stipe length and stipe diameter) and number of rings varied both within and between stands and sites, suggesting these measures are not reliable for estimating the age of this alga in the areas sampled. Stand density may be an important factor contributing to the variation in these morphome tric measures. Short-term (22 wk) field manipulations of stand density showed that plants at high density (30 plants m^-2) grew faster in stipe length and slower in stipe diameter than those at medium (6 plants m^-2) and low (2 plants m^-2) densities. Plants collected in a multi-site survey, however, showed no relationship between stand density and stipe morphology, indicating factors other than density also influence stipe growth Short-term (22 wk) field manipulations, which reduced ambient light levels by up to 58 %. had no significant effects on stipe morphology., , ,
Author: Hymanson, Reed, Foster, Carter
Date: 1990-01-01T00:00:00Z

Title: Radiometric age validation of Atlantic tarpon, Megalops atlanticus,
Description: An improved radiometric aging technique was used to examine annulus-derived age estimates from otoliths of the Atlantic tarpon, Megalops atlanticus. Whole otoliths from juvenile fish and otolith cores, representing the first 2 years of growth, from adult fish were used to determine 210Pb and 226Ra activity; six age groups consisting of pooled otoliths and nine individual otolith cores were aged. This unprecedented use of individual otolith cores to determine age was possible because of improvements made to the 226Ra determination technique. The disequilibria of 210Pb:226Ra for these samples were used to determine radiometric age. Annulus-derived age estimates did not agree closely with radiometric age determinations. In most cases, the precision (CV≤12%) among the otolith readings could not explain the differences. The greatest radiometric age was 78.0 yr for a 2045-mm-FL female, where the radiometric error encompassed the annulus-derived age estimate of 55 yr by about 4 yr. The greatest radiometric age for males was 41.0 yr for a 1588-mm-FL tarpon, where the radiometric error encompassed the annulus-derived age estimate of 32 yr by 1 yr. Radiometric age determinations in this study indicated that the interpretation of growth zones in Atlantic tarpon otoliths can be difficult, and in some cases may be inaccurate. This study provides conclusive evidence that the longevity of the Atlantic tarpon is greater than 30 years for males and greater than 50 years for females., Cited By (since 1996):9, CODEN: FSYBA, ,
Author: Andrews, Burton, Coale, Cailliet, Crabtree
Date: 2001-01-01T00:00:00Z

Title: Reply to "Robust estimates of decline for pelagic shark populations in the northwest Atlantic and Gulf of Mexico",
Description: Cited By (since 1996):20, , , ,
Author: Burgess, Beerkircher, Cailliet, Carlson, Cortés, Goldman, Grubbs, Musick, Musyl, Simpfendorfer
Date: 2005-01-01T00:00:00Z

Title: Brittle star distribution patterns and population densities on the continental slope off central California (Echinodermata: Ophiuroidea),
Description: The ophiuroid communities on the continental slope off central California were examined using box cores and trawls. Box cores were taken between 550 and 3085 m at sites southwest of the Farallon Islands, and otter and beam trawls were used below 2300 m at three sites between the Farallon Islands and Point Sur. Eighteen ophiuroid species from six families were identified. Eighty percent of the individuals collected with box cores belonged to two species, Ophiura leptoctenia and Ophiacantha normani, which were dominant between 1000 and 2000 m. The largest ophiuroid faunal break occurred at around 2000 m and was associated with elevated dissolved oxygen levels, decreasing sediment grain size, and increasing sediment organic content. A comparison of box-core and trawl data from below 2300 m showed that box cores undersampled the ophiuroid community on the continental slope, missing almost 50% of the species collected by trawls within the same area, whereas trawls underestimated ophiuroid densities, reporting on average 243 times fewer ophiuroids per m2 than did box cores. There was a change in species relative abundance patterns between sampling locations. Ophiuroids exhibited patchy spatial distribution patterns on both a small scale of around 0.1 m2 and a large scale on the order of 100-1000 s of square meters. (C) 2000 Elsevier Science Ltd., Cited By (since 1996):14, Invertebrates, CODEN: DSROE, ,
Author: Summers, Nybakken
Date: 2000-01-01T00:00:00Z

Title: Variations in the biomass of Antarctic krill (Euphausia superba) around the South Shetland Islands, 1996-2006,
Description: The time-series of acoustically surveyed Antarctic krill (Euphausia superba) biomass near the South Shetland Islands (SSI) between 1996 and 2006 is re-estimated using a validated physics-based model of target strength (TS), and a species-discrimination algorithm based on the length-range of krill in plankton samples to identify krill acoustically, derived from TS-model predictions. The SSI area is surveyed each austral summer by the US Antarctic Marine Living Resources Program, and the acoustic data are used to examine trends in krill biomass and to assess the potential impact of fishing to the reproductive success of land-based predators (seals and penguins). The time-series of recomputed biomass densities varies greatly from that computed using an empirical log-linear TS-model and fixed-ranges of differences in volume-backscattering strengths (ΔS v), conventionally used to identify krill acoustically. The new acoustic estimates of biomass are significantly correlated with both proportional recruitment and krill abundance estimated from zooplankton samples. Two distinct peaks in biomass (1996 and 2003) are in accord with recruitment events shown by net-based krill time-series. The foundation for the new TS-model and the associated krill-discrimination algorithm, coupled with the agreement between acoustic- and net-survey results, provides strong support for the use of the new analytical technique. Variable biases in the re-estimated krill biomass have been greatly reduced. However, survey variability increased as a result of the increased rejection of acoustic backscatter previously attributed to krill. Management of Southern Ocean krill stocks based on a precautionary approach may therefore result in decreased allocations of krill, given its dependence on the variability of survey estimates. © 2008 US Government and the Department of Commerce/National Oceanic and Atmospheric Administration/National Marine Fisheries Service/Southwest Fisheries Science Center., Cited By (since 1996):41, CODEN: ICESE, Antartica, ,
Author: Reiss, Cossio, Loeb, Demer
Date: 2008-01-01T00:00:00Z

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: Geographic variation in density, demography, and life history traits of a harvested temperate sex-changing reef fish
Description: Geographic variation in ecological and environmental factors may lead to intraspecific differences among populations. For the California sheephead (Semicossyphus pulcher), an important predator in kelp forests and a target of commercial and recreational fisheries, we evaluated the degree to which different populations exhibited variation in density, demography, and life history traits. We assessed biogeographic patterns of abundance through underwater visual census at 39 sites spanning a major portion of the species range (southern California, USA, to Baja California, Mexico) and made collections from seven focal sites to investigate geographic differences in demography and life histories. California sheephead densities were significantly greater in the southern part of their range and at offshore islands than along the mainland coast. At the focal sites, we found significant spatial variation in density, fecundity, size structure, growth rates, annual survivorship, and the timing of maturation and sex change. Density- and temperature-dependent effects helped to explain the intraspecific differences in these parameters. Studies such as this one will allow for demographic plasticity to be incorporated into future stock assessments. Management of temperate reef fishes may best be achieved on smaller spatial scales as we increase our understanding of geographic variation among populations.
Author: Caselle, Hamilton, Schroeder, Love, Standish, Rosales-Casián, Sosa-Nishizaki

Title: Long-term monitoring of krill recruitment and abundance indices in the Elephant Island area (Antarctic Peninsula),
Description: Krill distribution and density are reviewed for the Elephant Island area with regard to the representativeness of the study area (60°-62°30′S and 53°-57°30′W) for proportional recruit and density indices. Proportional recruitment indices were re-calculated applying the delta distribution approach introduced by de la Mare (1994a). The high interannual variability of krill recruitment is confirmed by the present analysis. Results are compared for one- and two-year-old krill (R1 and R2 respectively). Statistically significant fluctuations in krill density over the period 1977 to 1994 are also confirmed by this study using randomisation tests on an analysis of variance., Cited By (since 1996):33, Antarctica, Invertebrates, ,
Author: Siegel, De La Mare, Loeb
Date: 1997-01-01T00:00:00Z

Title: Age and sex of Common Murres Uria aalge recovered during the 1997-98 Point Reyes Tarball Incidents in central California,
Description: We examined 1,138 Common Murre Uria aalge carcasses recovered along the central California coast from November 1997 through March 1998 during the Point Reyes Tarball Incidents, a prolonged oiling event traced to the sunken vessel S. S. Jacob Luckenbach. We used head plumage, supraorbital ridge, and bursa of Fabricius, to classify age among carcasses as hatch-year (HY), or after-hatch year (AHY). We then separated AHY birds into two maturity categories based on gonad development: subadult and adult. The observed age class composition (14.6% HY, 37.6% subadult, and 47.8% adult) was not different from expected values generated with a stage-based matrix model that assumed a year-round resident population. The sex ratio for HY birds was equal (1.2:1 ), indicating little difference in at-sea distribution among male and female HY birds during winter. We found male-biased sex ratios in subadult (1.6:1) and adult (1.5:1) age classes. Sex-based differences in winter dispersal or colony attendance may have caused different risks to oiling among AHY birds. Mortality of mostly AHY murres during the Point Reyes Tarball Incidents and other oil spills has contributed to slow recovery of the central California population following historic and recent declines., Cited By (since 1996):11, Marine Mammals, Birds & Turtles, ,
Author: Nevins, Carter
Date: 2003-01-01T00:00:00Z

Title: FISH-Flow: A quantitative molecular approach for describing mixed clade communities of Symbiodinium
Description: Our understanding of reef corals and their fate in a changing climate is limited by our ability to monitor the diversity and abundance of the dinoflagellate endosymbionts that sustain them. This study combined two well-known methods in tandem: fluorescent in situ hybridization (FISH) for genotype-specific labeling of Symbiodinium and flow cytometry to quantify the abundance of each symbiont clade in a sample. This technique (FISH-Flow) was developed with cultured Symbiodinium representing four distinct clades (based on large subunit rDNA) and was used to distinguish and quantify these types with high efficiency and few false positives. This technique was also applied to freshly isolated symbionts of Orbicella faveolata and Orbicella annularis. Isolates from acutely bleached coral tissues had significantly lower labeling efficiency; however, isolates from healthy tissue had efficiencies comparable to cultured Symbiodinium trials. RNA degradation in bleaching samples may have interfered with labeling of cells. Nevertheless, we were able to determine that, with and without thermal stress, experimental columns of the coral O. annularis hosted a majority of clade B and B/C symbionts on the top and side of the coral column, respectively. We demonstrated that, for cultured Symbiodinium and Symbiodinium freshly isolated from healthy host tissues, the relative ratio of clades could be accurately determined for clades present at as low as 7 % relative abundance. While this method does not improve upon PCR-based techniques in identifying clades at background levels, FISH-Flow provides a high precision, flexible system for targeting, quantifying and isolating Symbiodinium genotypes of interest. © 2013 Springer-Verlag Berlin Heidelberg.
Author: McIlroy, Smith, Geller
Date: 2014-01-01T00:00:00Z

Title: Impacts of bay floor disturbances on benthic habitats in San Francisco Bay,
Description: Approximately 120 km2 of San Francisco Bay were mapped using archived multibeam bathymetry data and another ∼40.5 km2 were mapped using recently acquired sidescan sonar data. Imagery was collected in several parts of San Francisco Bay, typically between 10 and 30 m. These data were interpreted into potential habitat types and further evaluated for natural (normally-) and human-induced disturbances. Ninety-one distinct potential habitats were identified, of which 74 were composed of soft, 12 of mixed, and 5 of hard, substrates. Bay floor sediment samples, collected by the US Geological Survey and the National Ocean Survey of the National Oceanic and Atmospheric Administration, were used to document substrate composition and document ("ground-truth") habitat interpretations. The sedimentological history of the region extends back to approximately 10 Ma with the initiation of a major sediment depocentre in the tectonic graben formed between the Hayward-Calaveras and San Andreas fault zones. Modern sedimentation from fluvial input and tidal scouring and deposition has resulted in a dynamic and complex bay floor. Strong currents have produced large sediment waves and dune fields, rippled sediment patches, and scoured channel floors and walls. Soft habitats composed primarily of mud and/or sand dominate the region, whereas hard rocky and mixed habitats are relatively rare and occur mainly in shallow areas adjacent to peninsulas and islands. Anthropogenic effects such as dredge material and debris-fields, borrow pits, dredged channels, and blasted bedrock knolls and normal disturbances such as sand waves are distinctly displayed in the data covering ∼63.5 km2 of area and delineated on the habitat maps. With the increasing demand for construction aggregate and development in the greater San Francisco Bay area, and the need to maintain and expand dredged channels and lower bedrock knolls to allow the safe passage of deeper draft vessels, many potential habitats will be impacted., , ,
Author: Greene, Vallier, Bizzarro, Watt, Dieter
Date: 2007-01-01T00:00:00Z

Title: Let seeping oil lie,
Description: , , ,
Author: Foster
Date: 1993-01-01T00:00:00Z

Title: Increase in cetacean and seabird numbers in the Canal de Ballenas during an El Nino-Southern Oscillation event,
Description: In the Canal de Ballenas, central Gulf of California, primary productivity is based on tidal mixing and appears unaffected by ENSO events. Between the ENSO year of 1983 and the anti-ENSO year of 1985 the authors censused 4 piscivores (Bryde's whale Balaenoptera edeni; common dolphin Delphinus delphis; blue-footed booby Sula nebouxii, and brown booby S. leucoagster) and three planktivores (fin whale B. physalus; black storm petrel Oceanodroma melania; and least storm petrel O. microsoma). For all species the number of individuals sighted per hour declined by 77-94% over the 3 yr period. This suggests that during ENSO events the Canal de Ballenas may serve as a refugium of high productivity and prey abundance for these highly mobile marine animals., Cited By (since 1996):24, ,
Author: Tershy, Breese, Alvarez-Borrego
Date: 1991-01-01T00:00:00Z

Title: Reproductive biology of catsharks (Chondrichthyes: Scyliorhinidae) off the west coast of southern Africa,
Description: This study presents information on the reproductive biology of five southern African catshark species: Apristurus microps, A. saldanha, Apristurus sp., Galeus polli, and Scyliorhinus capensis. They were caught between Walvis Bay, Namibia, and Cape Agulhas, South Africa, from 50 to 1016 m deep. The reproductive mode of four species was oviparous, whereas G. polli exhibited aplacental viviparity. Males of all species attained first maturity slightly larger than females, and males of the four oviparous species attained a larger LTmax than females. The length at 50% maturity was similar for males and females in most species. All species matured at an LT > 75% of LTmax except for male Apristurus spp. and female G. polli, which matured at 71.2% and 68.8%, respectively, of LTmax. The egg case of A. microps has minute tendrils, whereas those of S. capensis were quite long, suggesting different egg-laying habitats. Fecundity in G. polli ranged from 5 to 13, and litter size increased in relation to increased female length. Embryos of G. polli were large, each measuring approximately 30% of female LT. Neonates of G. polli were common and appear to have a demersal lifestyle; those of the four oviparous species were entirely absent from the study. Gravid A. microps were found in summer and winter, indicating a protracted breeding cycle, but reproductively active S. capensis were caught only in winter. Prior to this study, reproductive information on these catsharks was largely lacking. © 2006 International Council for the Exploration of the Sea., Cited By (since 1996):23, CODEN: ICESE, ,
Author: Ebert, Compagno, Cowley
Date: 2006-01-01T00:00:00Z

Title: Surveillance for zoonotic and selected pathogens in harbor seals phoca vitulina from central California
Description: The infection status of harbor seals Phoca vitulina in central California, USA, was evaluated through broad surveillance for pathogens in stranded and wild-caught animals from 2001 to 2008, with most samples collected in 2007 and 2008. Stranded animals from Mendocino County to San Luis Obispo County were sampled at a rehabilitation facility: The Marine Mammal Center (TMMC, n = 175); wild-caught animals were sampled at 2 locations: San Francisco Bay (SF, n = 78) and Tomales Bay (TB, n = 97), that differed in degree of urbanization. Low prevalences of Salmonella, Campylobacter, Giardia, and Cryptosporidium were detected, in the feces of stranded and wild-caught seals. Clostridium perfringens and Escherichia coli were more prevalent in the feces of stranded (58% [78 out of 135] and 76% [102 out of 135]) than wild-caught (42% [45 out of 106] and 66% [68 out of 106]) seals, whereas Vibrio spp. were 16 times more likely to be cultured from the feces of seals from SF than TB or TMMC (p < 0.005). Brucella DNA was detected in 3.4% of dead stranded harbor seeds (2 out of 58). Type A influenza was isolated from feces of 1 out of 96 wild-caught seals. Exposure to Toxoplasma gondii, Sarcocystis neurona, and type A influenza was only detected in the wild-caught harbor seals (post-weaning age classes), whereas antibody titers to Leptospira spp. were detected in stranded and wild-caught seals. No stranded (n = 109) or wild-caught (n = 217) harbor seals had antibodies to phocine distemper virus, although a single low titer to canine distemper virus was detected. These results highlight the role of harbor seals as sentinel species for zoonotic and terrestrial pathogens in the marine environment., Harbor Seals
Author: Greig, Gulland, Smith, Conrad, Field, Fleetwood, Harvey, Ip, Jang, Packham, Wheeler, Hall

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