Ocean impact on fish chair's focus

by Stephen Forgacs
Staff writer

In formally bringing together fisheries and oceanography for the first time, the Faculty of Science has taken a step towards understanding the impact that physical and chemical changes in the oceans have on fish populations.

The first holder of a new Chair in the Ocean Environment and Its Living Resources, Prof. Paul J. Harrison, hopes that by combining the two disciplines, questions that do not fall into the traditional domains of oceanography or fisheries research can be answered.

"Fisheries science has been primarily concerned with the economic question of how much fish can be taken from the sea. Oceanography has been concerned with understanding the physics, chemistry, geology and biology of the oceans," says Harrison.

"Fisheries oceanography attempts to explain the abundance of certain economically important species of fish as a natural consequence of their evolution in hospitable oceanographic environments, or conversely, their diminishing abundance in previously favorable habitats."

The Fisheries Oceanography program has been 10 years in the works, says Harrison, since Oceanography/Zoology Prof. Emeritus Tim Parson recognized the need to link the disciplines. More recently, the support of an anonymous donor, the David and Lucile Packard Foundation, the Dept. of Fisheries and Oceans and others made creation of the chair possible.

As a first step in bringing fisheries and oceanography together, UBC recently hosted a Fisheries Oceanography Symposium to launch the new program.

Lectures given during the symposium will be published for use as an upper undergraduate and graduate textbook titled Fisheries Oceanography: A Science for the Next Millennium, which will provide guidelines for the next generation in fisheries oceanography research.

Creation of the chair has allowed the Dept. of Earth and Ocean Sciences to hire junior faculty member John Dower, who will join UBC in July as an assistant professor in fisheries oceanography.

Dower's expertise in larval fish, their feeding and ocean turbulence complements Harrison's expertise as a biological oceanographer specializing in the ocean's primary products, phytoplankton and zooplankton, and their regulation by various environmental factors.

The pair will work with UBC oceanographers and researchers at UBC's Fisheries Centre, who have particular strengths in modelling and fish stock analysis, as well as with federal government scientists in the Dept. of Fisheries and Oceans.

While Harrison and Dower will examine the impact of one- or two-year events such as El Niño, they will focus on the relationship between fish population and gradual changes in ocean climates, known as regime shifts, that take place over periods of 10 to 15 years.

Harrison lists evidence and examples that emphasize the need to understand the link between ocean conditions and changes in fish populations: stock collapses and failures in management models tend to coincide with major shifts in climate; there is increasing evidence that large changes in fisheries yield may be influenced by environmental changes in addition to overfishing; and several West Coast fisheries are managed using various proxy indices of ocean conditions with little understanding of the real mechanisms.

Researchers will draw on data such as information on ocean temperature and chemistry that has been recorded over a period of 40 years at Station P in the north Pacific, where a weather ship was stationed for decades.

Since the advent of satellite-based weather monitoring systems made the ship redundant in the 1980s, Harrison and other researchers travel to the location three times each year to take water samples and record conditions.

"We're trying to look at what factors in nature might cause these oscillations in fish populations," he says.

Harrison cites Gobi Desert dust storms in China as an example of a weather phenomenon that can have an effect on ocean productivity. Dust particles from desert storms deliver iron to the North Pacific Ocean. Iron enrichment affects phytoplankton production which could in turn affect fish stocks.

Harrison will continue to participate in international research groups such as the 15-country Joint Ocean Global Fluxes Study. Backed by the Natural Sciences and Engineering Research Council, the study is trying to understand the relationship between ocean carbon cycles and global warming.

He also takes part in the Global Ocean Ecosystem Dynamics (GLOBEC) program, which combines physical and biological sciences to determine how ocean physics influence the productivity of oceans and fisheries.