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Abstract

The impacts of climate change have been demonstrated to influence fisheries resources. One way climate has affected fish stocks is via persistent shifts in spatio-temporal distribution. Although examples of climate-forced distribution shifts abound, it is unclear how these shifts are practically accounted for in the management of fish stocks. In particular, how can we take into account shifting stock distribution in the context of stock assessments and their management outputs? Here, we discuss examples of the types of fish stock distribution shifts that can occur.

Abstract

Previous projection of climate change impacts on global food supply focuses solely on production from terrestrial biomes, ignoring the large contribution of animal protein from marine capture fisheries. Here, we project changes in global catch potential for 1066 species of exploited marine fish and invertebrates from 2005 to 2055 under climate change scenarios. We show that climate change may lead to large-scale redistribution of global catch potential, with an average of 30–70% increase in high-latitude regions and a drop of up to 40% in the tropics.

Abstract

We present and review information regarding recreational angling and exploited marine fish populations in California. A comparison of rockfish assemblages among three differently fished areas (one open to all fishing, another open only to recreational fishing, and a de facto marine protected area) revealed large differences in fish density, size structure, and species composition. The area open to all fishing harbored the highest density of rockfishes (7,212 fish/ha), although the size structure and species composition were dominated by small fishes.

Abstract

We report results from an oyster hatchery on the Oregon coast, where intake waters experienced variable carbonate chemistry (aragonite saturation state < 0.8 to > 3.2; pH < 7.6 to > 8.2) in the early summer of 2009. Both larval production and midstage growth (∼ 120 to ∼ 150 µm) of the oyster Crassostrea gigas were significantly negatively correlated with the aragonite saturation state of waters in which larval oysters were spawned and reared for the first 48 h of life.

Abstract

This chapter reviews the physical and ecological impacts of climate change relevant to marine and inland capture fisheries and aquaculture. It is noted that the oceans are warming but that this warming is not geographically homogeneous. The combined effect of temperature and salinity changes due to climate warming are expected to reduce the density of the surface ocean, increase vertical stratification and change surface mixing. There is evidence that inland waters are also warming, with differential impacts on river run off.

Abstract

Global climate change is impacting and will continue to impact marine and estuarine fish and fisheries. Data trends show global climate change effects ranging from increased oxygen consumption rates in fishes, to changes in foraging and migrational patterns in polar seas, to fish community changes in bleached tropical coral reefs. Projections of future conditions portend further impacts on the distribution and abundance of fishes associated with relatively small temperature changes.

Abstract

A statistical model is developed to link recruitment of eastern Bering Sea walleye pollock (Theragra chalcogramma) to variability in late summer sea surface temperatures and to the biomass of major predators. The model is based on recent advances in the understanding of pollock recruitment, which suggest that warm spring conditions enhance the survival of early larvae, but high temperatures in late summer and autumn are associated with poor feeding conditions for young-of-year pollock and reduced recruitment in the following year.

Abstract

Marine life is being affected by changes in ocean conditions resulting from changes in climate and chemistry triggered by combustion of fossil fuels. Shifting spatial distributions of fish species is a major observed and predicted impact of these oceanographic changes, and such shifts may modify fish community structure considerably in particular locations and regions. We projected future range shifts of pelagic marine fishes of the Northeast Pacific shelf seas by 2050 relative to the present.

Abstract

Three independent modeling methods—a nutrient-phytoplankton–zooplankton (NPZ) model (NEMURO), a food web model (Ecopath/Ecosim), and a bioenergetics model for pink salmon (Oncorhynchus gorbuscha)—were linked to examine the relationship between seasonal zooplankton dynamics and annual food web productive potential for Pacific salmon feeding and growing in the Alaskan subarctic gyre ecosystem.

Abstract

There is growing recognition that the Arctic is threatened by multiple human impacts including climate change and increased activities resulting from greater access due to retreating sea ice. Arctic sea ice cover has declined about 3% per decade over the satellite record (1979-present), with the six lowest annual sea ice minima occurring in the last 6 years (2007-12). The Alaska Arctic contains large petroleum reserves, and human activities related to energy extraction are expected to increase in the near future.

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