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Following Friday's horrific crash of the bus carrying the Humboldt Broncos junior hockey team, Canadians and the hockey community are searching for ways to support the team and their family members.Guest: Sheldon Kennedy, former member of the Swift Current Broncos and on the bus during that team's fatal crash in 1986(Photo: Obtained by Global News)Learn more about your ad choices. Visit megaphone.fm/adchoices

Following Friday's horrific crash of the bus carrying the Humboldt Broncos junior hockey team, Canadians and the hockey community are searching for ways to support the team and their family members.Guest: Sheldon Kennedy, former member of the Swift Current Broncos and on the bus during that team's fatal crash in 1986(Photo: Obtained by Global News)Learn more about your ad choices. Visit megaphone.fm/adchoices

The interactions between waves and currents can be complex, primarily because of the nonlinear relationships between the two. Nevertheless, in computational models it is often desirable to simplify, or even ignore, the coupling between waves and currents because of the computational expense. In order to assess the errors associated with different forms of wave-current coupling in a realistic coastal inlet environment, the STWAVE wave model and ADCIRC current model been applied to Humboldt Bay, California, the only deep-draft harbor in a 400-mile stretch along the Pacific coast of the continental United States. These models will also ultimately be used to help understand the details of sediment transport and the implications of alternative dredging schemes at Humboldt Bay. The models are initially validated and then examined under a variety of climatological wave and tidal forcing conditions using uncoupled, one-way coupled, and two-way coupled forms of the wave and current models. Current fields, radiation stress, wave height, wave period, and wave turning are compared in the coupled and uncoupled applications to determine the importance of modeling wave-current interaction accurately at Humboldt Bay. A general set of guidelines for coupled model application are presented based on the results from this study.

This article is from PLoS ONE , volume 9 . Abstract Background: During the last decade, new Neogene fossil assemblages from South America have revealed important clues about the evolution of seabird faunas in one of the major upwelling systems of the world: the Humboldt Current. However, most of this record comes from arid Northern Chile and Southern Peru and, in consequence, our knowledge of the evolutionary history of seabirds in the temperate transitional zone is negligible. A new Late Pliocene assemblage of fossil birds from the coastal locality of Horcon in Central Chile offers a unique opportunity to fill this gap. Principal Findings: Isolated bones of a medium-sized penguin are the most abundant bird remains. Morphological and cladistic analyses reveal that these specimens represent a new species of crested penguin, Eudyptes calauina sp. nov. Eudyptes is a penguin genus that inhabit temperate and subantarctic regions and currently absent in central Chile. Additionally, a partial skeleton of a small species of cormorant and a partial tarsometatarsus of a sooty shearwater have been identified. Conclusion/Significance: The Horcon fossils suggest the existence of a mixed avifauna in central Chile during the Pliocene in concordance with the latitudinal thermal gradient. This resembles the current assemblages from the transitional zone, with the presence of species shared with Northern Chile and Southern Peru and a previously unrecorded penguin currently absent from the Humboldt System but present in the Magellanic region. Comparison of Pliocene seabird diversity across the Pacific coast of South America shows that the Horcon avifauna represents a distinctive assemblage linking the living faunas with the Late Miocene ones. A comparison with the fossil record near the Benguela Current (west coast of southern Africa) suggests that the thermic gradient could play an important role in the preservation of a higher diversity of cold/temperate seabirds in the Humboldt Current.

The 2019 Humboldt Bay Symposium is a community-oriented conference focused on research and restoration of coastal ecosystems, and sustainable use and enjoyment of Humboldt Bay and the surrounding region April 12, 2019 - Session Three: Ocean Science Organizers: Frank Shaughnessy, Humboldt State University & Joe Tyburczy, California Sea Grant Extension Climate, Krill, and Contaminated Crabs on the North Coast: Insights from Ocean Observing in the California Current Eric Bjorkstedt, NOAA Southwest Fisheries Science Center

Ongoing global warming caused by climate change has been suggested to produce an intensification of upwelling-favorable winds along the coast of south-central Chile due to a poleward displacement of the South Pacific Anticyclone (SPA). Here we explore the extent to which these changes have influenced water column properties, inorganic nutrients, primary production, diatom abundances and net community metabolism (GPP/CR) in these shelf waters. Our analysis is based on a monthly time series (2003–2013) of in situ oceanographic and biological observations and experiments to assess gross primary production (GPP) and community respiration (CR) at a shelf station in central Chile (∼36.5°S), along with ancillary data on alongshore wind variability, river outflow and MODIS-derived surface fluorescence (nFLH). A reduction in river outflow from 2007 onwards, forced remotely by the poleward displacement of the SPA, resulted in a cooler and saltier water column, with lower dissolved Si:N ratios (Si(OH)4: NO3−) and net community metabolism shifting from high net autotrophy (mean GPP/CR = 10.9 ± 14) to a balance between production and respiration (GPP/CR = 1.17 ± 0.6). A key finding was that most of the observed inter-annual variability in diatom abundance and primary production rates from 2003 to 2013 could be explained by two opposite trends: a significant intensification of upwelling-favorable winds during early spring (October-November) post-2009, and a sustained drop in freshwater discharged by the main local river during the same period. A combination of more intense equatorward winds and weaker stratification of the water column may have driven mixing and turbulence beyond the levels that are suitable for diatom growth when the upwelling period began (October-November), and subsequently may have enhanced the offshore transport of nutrients and productivity during late summer months (February-March). Patterns revealed by the analysis of monthly composites of normalized surface fluorescence (nFLH) are consistent with this interpretation. Further intensification of upwelling-favorable winds, combined with changes in the pattern of precipitation and river discharges, may have negative effects on the composition, productivity, and carbon export in shelf waters of this and other coastal upwelling ecosystems.

This article is from PLoS ONE , volume 9 . Abstract The jumbo squid Dosidicus gigas plays an important role in marine food webs both as predator and prey. We investigated the ontogenetic and spatiotemporal variability of the diet composition of jumbo squid in the northern Humboldt Current system. For that purpose we applied several statistical methods to an extensive dataset of 3,618 jumbo squid non empty stomachs collected off Peru from 2004 to 2011. A total of 55 prey taxa was identified that we aggregated into eleven groups. Our results evidenced a large variability in prey composition as already observed in other systems. However, our data do not support the hypothesis that jumbo squids select the most abundant or energetic taxon in a prey assemblage, neglecting the other available prey. Indeed, multinomial model predictions showed that stomach fullness increased with the number of prey taxa, while most stomachs with low contents contained one or two prey taxa only. Our results therefore question the common hypothesis that predators seek locally dense aggregations of monospecific prey. In addition D. gigas consumes very few anchovy Engraulis ringens in Peru, whereas a tremendous biomass of anchovy is potentially available. It seems that D. gigas cannot reach the oxygen unsaturated waters very close to the coast, where the bulk of anchovy occurs. Indeed, even if jumbo squid can forage in hypoxic deep waters during the day, surface normoxic waters are then required to recover its maintenance respiration (or energy?). Oxygen concentration could thus limit the co-occurrence of both species and then preclude predator-prey interactions. Finally we propose a conceptual model illustrating the opportunistic foraging behaviour of jumbo squid impacted by ontogenetic migration and potentially constrained by oxygen saturation in surface waters.

This article is from PLoS ONE , volume 9 . Abstract The jumbo squid Dosidicus gigas plays an important role in marine food webs both as predator and prey. We investigated the ontogenetic and spatiotemporal variability of the diet composition of jumbo squid in the northern Humboldt Current system. For that purpose we applied several statistical methods to an extensive dataset of 3,618 jumbo squid non empty stomachs collected off Peru from 2004 to 2011. A total of 55 prey taxa was identified that we aggregated into eleven groups. Our results evidenced a large variability in prey composition as already observed in other systems. However, our data do not support the hypothesis that jumbo squids select the most abundant or energetic taxon in a prey assemblage, neglecting the other available prey. Indeed, multinomial model predictions showed that stomach fullness increased with the number of prey taxa, while most stomachs with low contents contained one or two prey taxa only. Our results therefore question the common hypothesis that predators seek locally dense aggregations of monospecific prey. In addition D. gigas consumes very few anchovy Engraulis ringens in Peru, whereas a tremendous biomass of anchovy is potentially available. It seems that D. gigas cannot reach the oxygen unsaturated waters very close to the coast, where the bulk of anchovy occurs. Indeed, even if jumbo squid can forage in hypoxic deep waters during the day, surface normoxic waters are then required to recover its maintenance respiration (or energy?). Oxygen concentration could thus limit the co-occurrence of both species and then preclude predator-prey interactions. Finally we propose a conceptual model illustrating the opportunistic foraging behaviour of jumbo squid impacted by ontogenetic migration and potentially constrained by oxygen saturation in surface waters.