scholarly journals Trophic ecology of three dominant myctophid species in the northern California Current region

2008 ◽  
Vol 373 ◽  
pp. 81-96 ◽  
Author(s):  
AV Suntsov ◽  
RD Brodeur
Keyword(s):  
Trophic Ecology ◽  
California Current ◽  
Northern California ◽  
Northern California Current ◽  
Current Region

Abundance, distribution, and feeding ecology of Pyrosoma atlanticum in the Northern California Current

2020 ◽  
Vol 651 ◽  
pp. 97-110
Author(s):  
JB Schram ◽  
HL Sorensen ◽  
RD Brodeur ◽  
AWE Galloway ◽  
KR Sutherland
Keyword(s):  
Trophic Level ◽  
Trophic Ecology ◽  
Isotope Analysis ◽  
California Current ◽  
Food Sources ◽  
Northern California ◽  
Abundance Distribution ◽  
Surface Salinity ◽  
Tropical Ocean ◽  
Northern California Current

During 2016-2018, unprecedented aggregations of the colonial pelagic tunicate Pyrosoma atlanticum were observed in the Northern California Current (NCC). Pyrosomes are common in tropical and sub-tropical ocean waters, but little is known about their abundance, distribution, and trophic ecology in mid-latitude systems. To assess these factors, pyrosomes were collected during cruises in the NCC in May and August 2017. A generalized additive model (GAM) was used to identify relationships between in situ environmental variables (temperature, salinity, fluorescence) and distribution and abundance patterns of pyrosomes in May 2017. Fatty acid (FA) profiles were then characterized as diet indicators, and bulk stable isotope analysis of carbon and nitrogen was used to examine spatial variations in potential food sources and trophic level. The GAM identified sea surface temperature and surface salinity as significant variables related to pyrosome densities. The most abundant FA in the pyrosomes was docosahexanoic acid (22:6ω3), which serves in pelagic systems as a biomarker for dinoflagellates. Common FA biomarkers for bacteria, carnivory, and dinoflagellates differed by latitude, suggesting that pyrosomes have different diets over a broad latitudinal range. The δ15N values of P. atlanticum indicate that pyrosomes may be feeding at a relatively low trophic level compared to other zooplankton groups in this region. Offshore pyrosomes had lower δ13C values than those collected on the shelf, suggesting incorporation of nearshore carbon in pyrosome tissues. Previously documented rapid reproduction and growth of pyrosomes coupled with efficient feeding behavior for common NCC plankters may support their continued presence in this mid-latitude region.

scholarly journals Surface Stress and Atmospheric Boundary Layer Response to Mesoscale SST Structure in Coupled Simulations of the Northern California Current System

2019 ◽  
Vol 148 (1) ◽  
pp. 259-287
Author(s):  
R. M. Samelson ◽  
L. W. O’Neill ◽  
D. B. Chelton ◽  
E. D. Skyllingstad ◽  
P. L. Barbour ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Wind Stress ◽  
Current System ◽  
California Current ◽  
Heat Fluxes ◽  
Neutral Stability ◽  
Northern California ◽  
Coupling Coefficients ◽  
California Current System ◽  
Northern California Current

Abstract The influence of mesoscale sea surface temperature (SST) variations on wind stress and boundary layer winds is examined from coupled ocean–atmosphere numerical simulations and satellite observations of the northern California Current System. Model coupling coefficients relating the divergence and curl of wind stress and wind to downwind and crosswind SST gradients are generally smaller than observed values and vary by a factor of 2 depending on planetary boundary layer (PBL) scheme, with values larger for smoothed fields on the 0.25° observational grid than for unsmoothed fields on the 12-km model grid. Divergence coefficients are larger than curl coefficients on the 0.25° grid but not on the model grid, consistent with stronger scale dependence for the divergence response than for curl in a spatial cross-spectral analysis. Coupling coefficients for 10-m equivalent neutral stability winds are 30%–50% larger than those for 10-m wind, implying a correlated effect of surface-layer stability variations. Crosswind surface air temperature and SST gradients are more strongly coupled than downwind gradients, while the opposite is true for downwind and crosswind heat flux and SST gradients. Midlevel boundary layer wind coupling coefficients show a reversed response relative to the surface that is predicted by an analytical model; a predicted second reversal with height is not seen in the simulations. The relative values of coupling coefficients are consistent with previous results for the same PBL schemes in the Agulhas Return Current region, but their magnitudes are smaller, likely because of the effect of mean wind on perturbation heat fluxes.

scholarly journals The interaction of physical and biological factors drives phytoplankton spatial distribution in the northern California Current

2020 ◽  
Vol 65 (9) ◽  
pp. 1974-1989
Author(s):  
Jeffrey W. Krause ◽  
Mark A. Brzezinski ◽  
John L. Largier ◽  
Heather M. McNair ◽  
Michael Maniscalco ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
California Current ◽  
Northern California ◽  
Biological Factors ◽  
Northern California Current

Implications of Pyrosoma atlanticum range expansion on phytoplankton standing stocks in the Northern California Current

2020 ◽  
Vol 188 ◽  
pp. 102424
Author(s):  
Jessica H. O'Loughlin ◽  
Kim S. Bernard ◽  
Elizabeth A. Daly ◽  
Samantha Zeman ◽  
Jennifer L. Fisher ◽  
...  
Keyword(s):  
Range Expansion ◽  
California Current ◽  
Northern California ◽  
Northern California Current ◽  
Standing Stocks
Sign in / Sign up

Export Citation Format

Share Document