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 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,...
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...
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...
This report reviews the state of the California Current System (CCS) between winter 2012 and spring 2013, and includes observations from Washington State to Baja California. During 2012, large-scale climate modes indicated the CCS remained in a cool, productive phase present since 2007. The upwelling season was delayed north of...
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. Jahncke, S. Bograd, F. Schwing, G.
S. Campbell, J. Hildebrand, W. Sydeman, S. Thompson, J. Largier, C
This report reviews the state of the California Current System (CCS) between winter 2012 and spring 2013, and includes observations from Washington State to Baja California. During 2012, large-scale climate modes indicated the CCS remained in a cool, productive phase present since 2007. The upwelling season was delayed north of...
Full Text:
Wells, B. K., Schroeder, I. D., Santora, J. A., Hazen, E. L., Bograd, S. J.,
Bjorkstedt, E. P
This report reviews the state of the California Current System (CCS) between winter 2012 and spring 2013, and includes observations from Washington State to Baja California. During 2012, large-scale climate modes indicated the CCS remained in a cool, productive phase present since 2007. The upwelling season was delayed north of...
The rapid decline of marine ecosystems worldwide and the failure of traditional single species management pushed for the development of ecosystem-based conservation measures such as marine protected areas (MPA) to slow the loss of marine biodiversity. One approach to MPA creation advocates targeting marine megafauna (e.g., marine mammals, seabirds, sharks,...
Variable ocean conditions can greatly impact lower trophic level prey assemblages in marine ecosystems, with effects propagating up to higher trophic levels. Our goal was to better understand how varying ocean conditions influence diets and niche overlap among a suite of low- to mid trophic level predators. We studied the...
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M, Hayes S, Harding J, Sydeman
WJ, Thompson SA, Warzybok P, Bradley R, JahnckeJ, Golightly RT
The ecological interaction between the largest coastal predator, the gray whale (Eschrichtius robustus) and the most abundant shallow water marcrozooplanktonic prey, mysids, were examined in a poorly-understood predator-prey relationship along the central Oregon coast. From 2002-2008, 83 seasonal gray whales were identified. These whales returned each year around Memorial Day...
Small pelagic fish represent a critical trophic link between plankton and large predators in marine upwelling ecosystems such as the California Current System. Populations of these fish are highly variable over time and are characterized by extreme fluctuations in abundance, which have significant ecosystem impacts. The causes driving
this instability...
Variable ocean conditions can greatly impact lower trophic level prey assemblages in marine ecosystems, with effects propagating up to higher trophic levels. Our goal was to better understand how varying ocean conditions influence diets and niche overlap among a suite of low- to mid trophic level predators. We studied the...
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AN ABSTRACT OF THE THESIS OF
Amanda J. Gladics for the degree of Master of Science in Marine
Vibrio parahaemolyticus is a foodborne pathogen recognized as the leading cause of acute gastroenteritis associated with consumption of raw and undercooked seafood, particularly raw oysters, with major symptoms of nausea, vomiting, abdominal cramps and diarrhea. It is estimated that 45,000 cases of V. parahaemolyticus infection occur each year in the...
Oysters are filter-feeding bivalves, which filter water for nutrients and often accumulate contaminants and human pathogens such as Vibrio parahaemolyticus and Vibrio vulnificus naturally occurring in the marine environment. These naturally occurring pathogens have been frequently isolated from raw shellfish, particularly oyster, in the United States and are recognized as...
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...
Bird scaring lines (BSLs) protect longline fishing gear from seabird attacks, save bait, reduce incidental seabird mortality and are the most commonly prescribed seabird bycatch mitigation measure worldwide. We collaborated with fishermen to assess the efficacy of applying BSL regulations from the demersal longline sablefish fishery in Alaska to a...
Concurrent measurements of predator and prey δ¹⁵N isotope values demonstrated that a cross-shelf
isotopic gradient can propagate through a marine food web from forage species to top-tier predators and
indicate foraging areas at a scale of tens of kilometers. We measured δ¹³C and δ¹⁵N in muscle tissues of
thick-billed murres...
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...
The distribution of mobile marine predators often reflects underlying dynamic ecological processes. The geographical focus of this PhD is the South Taranaki Bight (STB) of New Zealand, where wind-driven coastal upwelling generates productivity and prey to support a blue whale foraging ground. The STB is also New Zealand’s most industrial...
The Bering Sea is a highly productive ecosystem with abundant prey populations in the summer that support some of the largest seabird colonies in the Northern Hemisphere. In the fall, the Bering Sea is used by large numbers of migrants and post-breeding seabirds. We used over 22000 km of vessel-based...
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populations and spatial
coherence with prey in the southeastern Bering Sea
Robert M. Suryan1,*, Kathy J