CHALLENGES AND OPPORTUNITIES OF OFFSHORE AQUACULTURE IN THE PACIFIC NORTHWEST

Langdon*, C.

Coastal Oregon Marine Experiment Station and Dept. Fisheries and Wildlife,
Hatfield Marine Science Center,
Oregon State University,
2030 S. Marine Science Drive,
Newport, Oregon 97365 Projected high rates of global and US population growth coupled with declines in many wild fisheries will put increasing pressure on aquaculture to meet future consumer demand for seafood. The US currently imports about 80% of its seafood, resulting in a large annual trade deficit of about $10 billion and a dependence on other countries to supply affordable, high-quality seafood in the future. Offshore aquaculture has been identified by NOAA and other organizations as a possible means of providing the US with a sustainable domestic source of seafood.

The Pacific Northwest offers some unique opportunities for offshore aquaculture, such as 1) clean, cold seawater that allows production of valuable cold-water species, 2) high wave and wind energy that could provide offshore facilities with sources of power and 3) a strong fishing community that could participate in farming initiatives.

In 2008, a forum was held at the Hatfield Marine Science Center, Oregon State University, Oregon, US, to discuss the potential of offshore aquaculture in the Pacific Northwest. The forum was attended by a wide range of participants, including scientists, administrators, fishing industry representatives, non-profit organizations and the media. Details of participants, the program and findings are given on the forums web site: Error! Hyperlink reference not valid. .

The forum made two overarching recommendations: 1) education and outreach should be undertaken to discuss the challenges and opportunities of offshore aquaculture for local communities and 2) demonstration projects should be established to determine technical, biological, economic and environmental aspects of offshore aquaculture. These recommendations and other findings of the forum will be presented.

SUSTAINABLE AQUACULTURE: THE CHANGING HORIZON

William A. Wurts

Kentucky State University CEP, UK Research and Education Center
P.O. Box 469, Princeton, KY 42445 USA
http://www.ca.uky.edu/wkrec/Wurtspage.htm Debates and discussions about sustainable aquaculture commonly address definitions, policy and legislation but rarely encompass culture practices or industry structure. Sustainable practices should integrate social, economic and environmental concerns. The best approaches would not tax environmental carrying capacity, deplete resources or negatively impact sensitive local and regional ecosystems. Ultimately, future sustainable technologies should fully integrate and exploit environmental productivity while minimizing or eliminating the ecological footprint.

Much of the intensive aquaculture industry has a highly centralized structure with respect to production and distribution. This centralized development has flourished around energy rich cultures and economies. Using United States Department of Energy (DOE) estimates, one can project that recent rates of global crude oil consumption will exhaust the proved world reserves in approximately 36 years. How will increased costs or shortages of gasoline, diesel fuel and electricity affect the sustainability or survival of the current production systems? Does a large, centralized industry provide more jobs and profit or a better quality of life (per capita) than widely dispersed, small scale operations producing at local or district levels?

Wastes that result from the high stocking densities and heavy feeding rates of intensive aquaculture push the production unit beyond its (biological) environmental carrying capacity. This necessitates the use of energy and mechanization to maintain acceptable water quality. Furthermore, waste nutrients are discharged with water when the production system is drained.

Aquatic nitrogen loads generated from the sewage effluent of a growing, global human population (15 billion vs. 6 billion people) may prevent the legal discharge of any aquacultural effluents. Nutrient recycling (converting nitrogen back to protein) through different polyculture systems could be more practical and efficient than controlling or treating the effluents associated with traditional, intensive monoculture practices. Phytoplankton and zooplankton occupy sizable respiratory (oxygen consumption) niches in the production pond environment -- and have no market value. Careful selection of suitable filter feeding fish and mollusks for polyculture could open up these niches for production of species with greater economic value. However, rates of plankton removal must be balanced with population growth rates of the plankton communities harvested. Perhaps pond plankton could be mechanically harvested for feed and nutritional supplements and/or biofuels as well.

Sustainability may be the aquaculture industry's ability to adapt on a planet with a human population that is swelling exponentially and continues to consume its limited supply of non-renewable resources at an alarming rate. Will humanity continue to expand mindlessly? Or can we adapt through self-awareness?