SCRIPPS CONTACTS: Mario Aguilera
or Cindy Clark
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FOR RELEASE: FEBRUARY 15, 2002

OCEAN ILLS MISDIAGNOSED: SCRIPPS SCIENTIST STRESSES HISTORY IN DEVELOPING STRATEGIES FOR SEA LIFE RESTORATION
New "video science short" illustrates historical approach to biodiversity management

Jeremy Jackson (far right) during filming of the video science short "Rediagnosing the Oceans"

For more than 100 years, fisheries around the world have been mismanaged due to an inaccurate evaluation of the true state of marine ecosystems. Lack of a full historical perspective, particularly the extent of impacts from overfishing in the oceans, has led to this incomplete picture. Jeremy Jackson, a professor at Scripps Institution of Oceanography at the University of California, San Diego, contends that understanding the stark magnitude of historical overfishing is the first step in developing scientifically rigorous and bold strategies for the restoration and sustainable development of the oceans. In a symposium he organized for the 2002 American Association for the Advancement of Science (AAAS) annual meeting in Boston, Jackson will stress the importance that recent groundbreaking research bears upon strategies for protecting sea life and restoring their richness.

"We need to reach back centuries to understand that historical overfishing is the primary driver of the collapse of coastal ecosystems worldwide," said Jackson. "Baselines used for fisheries management and conservation grossly underestimate the impacts of historical fishing on abundance of pristine populations and the structure and function of marine ecosystems."

Jackson contends that debilitating impacts from fishing, starting centuries ago, set off sequences of events that resulted in population explosions of sea urchins that overgrazed kelp forests, algae that smothered reef corals, slime molds that killed seagrasses, and microbial outbreaks that caused eutrophication, hypoxia, and diseases.

Jackson likens the situation to a medical crisis: Doctors have a much better chance of saving a patient’s life when they know the patient’s medical history. To illustrate this, Jackson and filmmaker Randy Olson have produced a five-minute "video science short" entitled "Rediagnosing the Oceans." The film presents four "case studies" in which marine ecosystem problems are described. An initial "diagnosis" of each problem is given, and the more recent "rediagnosis" is provided. It will be screened publicly for the first time at a reception for marine scientists hosted by Seaweb and COMPASS in conjunction with the 2002 AAAS meeting on Saturday, Feb. 16 at 6:30 p.m. (Space is limited for this event; those interested may contact Jessica Brown at (202) 497-8375.) The video can be seen at oceanRx.org.

Jackson recently led a team of 19 researchers in a startling study published in the journal Science that documents the widespread damage overfishing has caused on ecosystems such as kelp forests, coral reefs, and estuaries. The group uncovered impacts through hundreds of years in paleoecological, archaeological, and historical records.

Overfishing is the primary driver of the collapse of coastal ecosystems worldwide, Jackson now believes, and the decimation has triggered a series of ecosystem problems seen throughout the world today.

The first phase of this process is the catastrophic overfishing of megafauna, including whales, sea cows, monk seals, crocodiles, sea turtles, swordfish, sharks, giant codfish, and rays. Dwindling numbers hindered them from interacting in "ecologically significant ways with other species," Jackson says, and the losses allowed smaller species further down the food chain to fill the ecological vacuum.

The next phase of decline is the sudden collapse of "architectural" species such as kelp, oysters, reef corals, giant sponges, and seagrasses. Jackson says that these species built vast and complex three-dimensional habitats "that are the forests and grasslands of the oceans."

Those events led to the third phase, the outbreak of microbes, including species responsible for toxic plankton blooms, fish kills, and diseases.

Jackson agrees that pollution, introduced species, and climate change also have contributed to the second and third phases of ecosystem collapse, but stresses that these problems should not be addressed independently of their histories.

"Responding only to current events on a case-by-case basis cannot solve the ocean’s problems because impacts of human disturbance are synergistic and have deep historical roots," says Jackson. "Ecological extinctions make ecosystems more vulnerable to other natural and human disturbances."

But all hope is not lost, he says.

Most marine species thought to be ecologically extinct are probably still present in sufficient numbers for successful restoration with proper management. His optimism is in striking contrast with the outlook for most terrestrial systems, where many or most large animals are already extinct.

Marine protected areas (MPAs) and restricted harvests are essential measures for restoration, he says.

"Getting marine biodiversity back implies setting aside very large areas of the world’s oceans for protection," said Jackson. "Our historical analyses strongly reinforce the urgency that we begin such protective measures immediately."

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