Satellite imagery of chlorophyll a concentration (chl a) provides the only holistic perspective
of productivity in marine ecosystems worldwide, yet its utility for understanding and
predicting the distribution of upper trophic-level predators remains equivocal. We tested the
hypothesis that remotely sensed chl a measurements spanning a decade can predict marine...
Over recent decades, the marine ecosystems of Prince William Sound (PWS), Alaska have experienced the concurrent effects of a major anthropogenic disturbance, the 1989 Exxon Valdez oil spill (EVOS), and a dynamic atmospheric-oceanic environment. Studies of top marine consumers can provide insights into processes of ecosystem change. Using data collected...
Upwelling in eastern boundary current systems is a primary driver of ecosystem productivity. Typically, peak upwelling occurs during spring and summer, but winter upwelling may also be important to ecosystem functions. In this study, we investigated the hypothesis that winter and spring/summer upwelling, operating through indirect trophic interactions, are important...
As colony-specific wintering ecology of small and medium-sized seabirds is poorly understood, it has been generally assumed that winter conditions have the same effect on all individuals from any given colony. However, advances in global positioning technology now allow researchers to investigate movements of smaller seabirds. We tracked black-legged kittiwakes...
This report describes the state of the California Current System (CCS)—meteorological, physical, chemical, and biological—from January 2003 to the spring of 2004. The area covered in this report ranges from Oregon coastal waters to southern Baja California. Over the past year, most physical, chemical, and biological parameters were close to...
In marine ecosystems, rising atmospheric CO2 and climate change are associated with concurrent shifts in temperature, circulation, stratification, nutrient input, oxygen content, and ocean acidification, with potentially wideranging biological effects. Population-level shifts are occurring because of physiological intolerance to new environments, altered dispersal patterns, and changes in species interactions. Together...
This report is the eighth in a series that describe recent oceanographic observations within the California Current system, from Oregon to Baja California. The emphasis here is placed on the observations conducted concurrently by the CalCOFI (California Cooperative Oceanic Fisheries Investigations), IMECOCAL (Investigaciones Mexicanas de la COrriente de CALifornia), and...
This report summarizes the recent state of the California Current System (CCS), primarily during the period of April 2004 to January 2005. The report is based on observations made between Oregon and Baja California by various ocean observing programs. The CCS was not forced by any coherent basin-wide processes during...
This report summarizes physical and biological conditions in the California Current System (CCS), from Oregon to Baja California, in 2001 and 2002. The principal sources of the observations described here are the CalCOFI (California Cooperative Oceanic Fisheries Investigations), IMECOCAL (Investigaciones Mexicanas de la Corriente de California), and U.S. GLOBECLTOP (Global...
Marine heatwaves (“MHWs”) are discrete periods of anomalously warm ocean conditions that can lead to shifts in the distribution and abundance of marine organisms. Low-trophic level, pelagic forage species are frequently among those affected by MHWs, often resulting in considerable impacts upon their predators. In the North Atlantic Ocean, Atlantic...
The state of the California Current system (CCS) since spring 2010 has evolved in response to the development of cooler La Nina following the dissipation of the relatively weak and short-lived El Nino event of 2009-2010. The 2009-2010 El Nino appears to have dissipated quite rapidly in early spring 2010,...
Most benthic marine fishes have a biphasic life cycle with a dispersive pelagic larval stage that spends weeks to months in the plankton before metamorphosing into juveniles and settling to benthic habitats. The magnitude of mortality during the early life stages of marine fishes typically drives variability in year-class strength....
The Northern California Current (NCC) ecosystem exhibits extreme seasonal, interannual and interdecadal shifts in the abiotic environment and shifts in primary and higher production. This variability is also apparent in the spatial structure of the ecosystem with nearshore-shelf waters (<150 m isobath) being highly productive and having a different community...
Understanding how wetland birds use habitat is pivotal to developing successful and
beneficial conservation strategies. Although it has been an ardent topic in forest
research for some time, how species interact with the spatial patterning of habitat
across a landscape (i.e., landscape structure) has been more or less neglected in...
Predatorprey interactions are a primary structuring force vital to the resilience of marine communities and sustainability of the worlds oceans. Human influences on marine ecosystems mediate changes in species interactions. This generality is evinced by the cascading effects of overharvesting top predators on the structure and function of marine ecosystems....
Worldwide, in recent years capture fisheries targeting lower-trophic level forage fish and euphausiid crustaceans have been substantial (∼20 million metric tons [MT] annually). Landings of forage species are projected to increase in the future, and this harvest may affect marine ecosystems and predator-prey interactions by removal or redistribution of biomass...
We used a combination of seabird data (both fishery-dependent and fishery-independent) and fishing-effort data to evaluate the relative fisheries risk of five west coast groundfish fisheries and oneshrimp fishery to black-footed (Phoebastria nigripes), short-tailed (P. albatrus) and Laysan albatrosses(P. immutabilis). To assess risk, an overlap index was derived as the...
The state of the California Current System (CCS)
since spring 2011 has evolved in response to dissipation
of La Niña through spring and summer, resurgence of
cooler La Niña conditions in fall and winter, and finally
a transition towards ENSO-neutral conditions in spring
2012. The resurgence of La Niña was...
In 2013, the California current was dominated by
strong coastal upwelling and high productivity. Indices
of total cumulative upwelling for particular coastal
locations reached some of the highest values on record.
Chlorophyll a levels were high throughout spring and
summer. Catches of upwelling-related fish species were
also high. After a...
In 2014, the California Current (~28˚–48˚N) saw average, or below average, coastal upwelling and relatively low productivity in most locations, except from 38˚–43˚N during June and July. Chlorophyll-a levels were low throughout spring and summer at most locations, except in a small region around 39˚N. Catches of juvenile rockfish (an...