Hiromichi Ueno, Ph.D.^1
1Faculty of Fisheries Science, Hokkaido University
March 04, 2015 11:00 (PST)

Temporal and spatial variation in growth factors of Pacific salmon.

Dr. Ueno is an Associate Professor at Hokkaido University in Hokkaido, Japan. He has a PhD (2003) and Masters (2000) in Oceanography from the University of Tokyo, where he also later performed postdoctoral research. His research focuses on four main topics: 1) mesoscale eddies, physical characteristics and its impact on marine ecosystem; 2) pacific salmon and the physical environment affecting their growth; 3) temperature inversions and haloclines in the subarctic North Pacific; and 4) the physical environment and its impact on marine ecosystems in the Chukchi Sea.

This talk will start with the introduction of international intensive course for sustainable fishery resource use at Hokkaido University toward building a joint program in the North Pacific on board T/V Oshoro-maru. I will also talk about temporal and spatial variation in growth factors of Pacific salmon from the view point of bioenergetics. The prey-density function for consumption is used as the growth factor. For the estimation of the prey density, we used zooplankton density obtained from an ecosystem model, NEMURO embedded in a 3-D physical model. In this study we focus on the three species of Pacific salmon (chum, pink and sockeye), zooplankton feeders whose biomass exceeds 90% of Pacific salmon. Empirical Orthogonal Function (EOF) analysis is conducted for the growth factor in the subarctic North Pacific during 1948–2007. The growth factor of Pacific salmon varies in a decadal timescale. The variation of the growth factor in the Bering Sea, the western subarctic gyre and the eastern subarctic North Pacific are consistent with the variation of total catch of chum, pink and sockeye salmon.