Variations in ocean conditions influenced by climate fluctuations may impact fish populations by changing their spatial distribution, physiology, survival, and other ecological features. Somatic growth is a crucial aspect of the biology of fishes and an important contributor to biomass fluctuations. Climate variability also affects somatic growth rates along the...
Predicting recruitment, which is dependent on parent stock size and climate, is vital for forecasting productivity of fish stocks. The effects of climate can be analyzed via the use of climate indices. Three climate indices, the Pacific Decadal Oscillation, the North Pacific Gyre Oscillation, and the Oceanic Niño Index, describe...
Early life stages of marine fishes exert substantial control on the productivity and resilience of marine fisheries, as these life stages represent periods of extreme mortality. Additionally, eggs and larvae of marine fishes respond rapidly to environmental change and can thus be used to infer ecosystem-wide responses to climate change...
Changes in ocean conditions influenced by climatic fluctuations have lead to changes in individual species distributions, which alter the diversity, communities and species interactions across marine ecosystems worldwide. Assessing the species composition and identifying regions and habitats that can safeguard the persistence of biota are critically important. In this dissertation,...
The commercial groundfish fishing industry and groundfish research have a long concurrent history of activity on the Oregon continental margin. Within the non-whiting groundfish fishery, the target species are primarily flatfishes, sablefish, lingcod, and rockfishes, though landings of each have fluctuated over time. Recent work shows that over the past...
Changes in environmental conditions in marine ecosystems could directly or indirectly influence distribution, abundance, settlement, and size at settlement of flatfish. Understanding species-specific and age-specific responses to environmental variability is important for managing commercially important flatfish stocks. Slope-spawning flatfish whose offspring rely on extensive drift from the slope (spawning) to...
Observations of the Oregon coast’s physical oceanography over the last few decades have revealed falling dissolved oxygen levels associated with seasonal upwelling, as well as rising water temperatures. In extreme cases, these changes have been associated with die-offs, redistribution, and decreased abundance and diversity of benthic fish and invertebrates. Many...
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LorenzoCiannelli
Observations of the Oregon coast’s physical oceanography over the
The Pacific coast groundfish fishery is a diverse, important and lucrative commercial and recreational fishery. Part of this fishery’s monitoring process includes regular fishery-independent surveys for stock assessment. Although these fishery-independent surveys are cost-effective, they are susceptible to scientific uncertainty, and they do not currently sample in nearshore (water depth...
When adult spawning and juvenile settling locations of marine fishes are
geographically separated, their early life history stages must rely on transport and
their own behavior to move them toward suitable habitats for successful recruitment
to the juvenile phase. Variations in climate may reduce the availability of spawning
and juvenile...
This study investigated long-term (1961-2008) changes in albacore (Thunnus alalunga) abundance and distribution in relation to local environmental and large-scale climate indices in the Northeastern Pacific using time series and spatial analyses. Prior to the time series analysis, a wavelet analysis was conducted to examine nonrandom patterns of cyclical variability...
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LorenzoCiannelli
This study investigated long-term (1961-2008) changes in albacore