The Oregon Dead Zone

Russell Sadler

The Middle East is in flames. Confidence in the Bush regime and the Republican-dominated Congress is so low that control of the national legislature is up for grabs this November.

Put it all on the back burner. Something with potentially more far-reaching consequences has just showed up in the news -- again. The “Dead Zone” is back off the Oregon Coast.

Dead zones are bodies of water with insufficient oxygen to sustain marine life. Scientists call this process eutrophication. The term usually means the introduction of chemical nutrients -- usually nitrogen or phosphorus -- into an ecosystem that creates large algae blooms. Bacteria consume the dead and dying algae using up the oxygen in the water. Marine life that depends on oxygen cannot survive.

This process usually occurs in lakes, rivers, bays and large enclosed bodies of water like the Great Lakes, or the Gulf of Mexico. Scientists have identified about 150 “dead zones” around the world.

But the “dead zone” off the Oregon Coast has a different cause that has scientists mystified. It appears that unusual wind patterns off the coast are causing nutrient-rich deep sea water to rise to the surface closer to shore than usual. Scientists call this “upwelling.” Upwelling normally brings important nutrients to marine life. Under these unusual wind conditions, however, nutrient-rich deep sea water encourage large algae blooms near shore in the spring. The algae die and -- just like eutrophication -- the bacteria that consumes dead and dying algae and use up the oxygen in the water. Aquatic life dies.

For the last five years, researchers have discovered suffocated fish and crabs off the Oregon coast. The “dead zone,” first observed in 2002, has quadrupled in size and is now as large as Rhode Island -- about 1,235 square miles. The dead zone lasts a few weeks and disappears when the winds shift.

At first scientists thought the “dead zone” might be related to the El Nino and La Nina episodes or some long term ocean cycles. But the dead zones appearing for five straight years raises questions about those theories.

Dr. Jane Lubchenco, an Oregon State University marine biologist, suggests climate change may be a factor because there is no other apparent explanation for the altered wind patterns.

The media can get a bit provincial about these matters -- Oregon reporters are concerned about the dead zone “off the Oregon Coast.” But the effects of these unusual wind patterns and their consequences are being observed up along the West Coast of the USA and British Columbia.

One interesting finding: Seabird populations that scientists have been studying -- sometimes for decades -- suddenly began crashing.

Off Southern California, scientists from the Scripps Institute of Oceanography concluded fish larvae are down 50 percent and there have been massive kelp dieoffs. In the last 30 years, the upper 300 feet of the Pacific ocean has has warmed significantly. Scripps has been recording ocean temperatures since 1919.

In California’s Farallon Islands, and British Columbia’s Triangle Island, populations of Cassins auklet failed to breed successfully in 2005. Scientists diagnosis? Starvation.

Off Washington’s Tatoosh Island common murre populations plummeted. All along the Washington and Oregon Coast common murres and Brandt’s cormorants died in droves. Scientists’ diagnosis? Starvation. Their usual ocean food was not available.

At a meeting in Seattle last January, 45 scientists evolved the theory about the unusual wind patterns and it’s effect on reducing the food supply for seabirds. When the winds do blow they are suspected of creating the “dead zone” off the Oregon Coast. When these wind do not blow, they are suspected of creating sea conditions that reduce the seabirds’ food supply.

Is this a silly preoccupation with dying tweety-birds?

The seabirds -- and the Dungeness crab -- are symbols like the canary in the coal mine. Eventually, the forces that damage an ecosystem so it cannot support seabirds and marine life left unaltered will damage the ecosystem sufficiently to affect the humans that depend on it, especially if they involves the aquatic food supply as scientists now suspect.

None of this talk about changing weather patterns should lessen concern about ocean pollution, which is extensive and serious. The Los Angeles Times just published a thorough five-part series on ocean pollution.

The unusual wind patterns apparently causing “dead zones” and suffocating the forage fish and other aquatic life that crabs and seabirds feed on create consequences that should not be taken lightly. They are potentially more damaging than war in the Middle East or even a change in control of Congress.

By Russell Sadler Aug. 13, 2006