Larval supply determines year-class strength of fisheries and complex ecological
interactions among adults of benthic marine species. In upwelling regions, a latitudinal cline in
the intensity and persistence of upwelling is thought to affect larval advection and recruitment,
thereby regulating the intensity of interactions in adult populations and communities. We...
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) and (B) 1-way ANOVA testing whether larvae were found farther offshore during different oceanographic
An introduced population of European green crabs Carcinus maenas was established in San Francisco Bay (California, USA) prior to 1989. Subsequently, their larvae were likely carried northward into the embayments of Oregon, Washington (USA), and British Columbia (Canada) by the unusually strong Davidson Current during the winter of the El...
Alongshore transport was estimated from the gridded AVISO altimeter data and water level data from NOAA tide gauges (1993–2010) for the northern California Current (NCC) system. The biomass of the cold neritic copepods including Calanus marshallae, Pseudocalanus mimus and Acartia longiremis (dominants in the eastern Bering Sea, coastal Gulf of...
The zooplankton of the northern California Current are typically characterized by an abundance of lipid-rich copepods that support rapid growth and survival of ecologically, commercially, and recreationally valued fish, birds, and mammals. Disruption of this food chain and reduced ecosystem productivity are often associated with climatic variability such as El...
Early ocean residence is considered a critical period for juvenile salmon although specific survival mechanisms are often unidentified and may vary by species or life stage. Columbia River spring-run Chinook salmon Oncorhynchus tshawytscha abundance has declined dramatically since the early 1900s. To elucidate mechanisms of early marine survival, we tested...
Research on regulatory mechanisms in biological populations often focuses on environmental covariates. An integrated
approach that combines environmental indices with organismal-level information can provide additional insight on
regulatory mechanisms. Survival of spring/summer Snake River Chinook salmon (Oncorhynchus tshawytscha) is consistently
low whereas some adjacent populations with similar life histories experience...
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, Peterson WT, Baptista AM (2014) Assessing the Relative
Importance of Local and Regional Processes on the
Summertime wind stress along the coast of the northwestern United States typically exhibits intraseasonal oscillations (ISOs) with periods from ≈15 to 40 days, as well as fluctuations on the 2- to 6-day “weather-band” and 1-day diurnal time scales. Coastal upwelling of cool, nutrient-rich water is driven by extended periods of...
The Moult Rate (MR) method has been used widely to derive stage-specific growth rates in juvenile copepods. It is the most common field-based method. Unfortunately, the equation underlying the method is wrong and, consequently, large errors in juvenile growth rate estimates are widespread. The equation derives growth from the mean...
Generalized additive models (GAMs) were used to investigate the relationships between annual recruitment of natural coho salmon (Oncorhynchus kisutch) from Oregon coastal rivers and indices of the physical ocean environment. Nine indices were examined, ranging from large-scale ocean indicators, e.g., Pacific Decadal Oscillation (PDO), to indicators of the local ecosystem...
Diets of juvenile coho Oncorhynchus kisutch and Chinook O. tshawytscha salmon
are made up primarily of winter-spawning fish taxa in the late-larval and early juvenile stages that
are undersampled in plankton and larger trawl nets. Although we have no direct measure of the
availability of fish prey important to juvenile...