Marine Experts Unveil Secrets of Coastal Conservation

By Cat Lazaroff

WASHINGTON, DC, February 19, 2003 (ENS) - New findings about the dynamics of coastal ocean ecosystems are prompting marine scientists to abandon long held assumptions about life in the sea and how best to protect it. Working along coasts from California to the Caribbean, researchers say they have cracked the "black box" of coastal ecosystems, revealing the inner workings of the near shore marine environment.

The results of research into topics as tiny as microscopic fish larvae, and as broad as the 1,200 mile long California Current that sweeps the west coast of the United States, have brought new light to questions about how to predict and manage coastal ecosystems and marine populations. At a scientific symposium last weekend at the American Association for the Advancement of Science (AAAS) annual meeting in Denver, Colorado, a team of scientists said their studies show an urgent need for governments to overhaul existing laws aimed at protecting marine ecosystems.

Jane Lubchenco leads the PISCO team. (Photo courtesy PISCO)

"Coastal zones are not only home to over 50 percent of Americans - they are also home to a great majority of commercial and non-commercial marine species, as well as pivotal for industrial and recreational activities. The grand challenge is to use coastal oceans without misusing them," added Lubchenco, former president of AAAS and a member of the Pew Oceans Commission. "Our new findings will greatly aid ocean protection, restoration and sustainable use."

Lubchenco leads an interdisciplinary team of more than 100 ecologists, oceanographers, geneticists and engineers studying the coastal zone, extending about 10 kilometers (about six miles) out from the shore. This near shore region is often called "the bad zone" because its three dimensional nature, complex currents, shallow water and high wave energy have stymied oceanographers and their large vessels.

Now, scientists from the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO), which includes Oregon State University, Universities of California at Santa Barbara and Santa Cruz and Stanford University's Hopkins Marine Station, are comprehensively exploring the coastal zone along the U.S. West coast. For the first time, these researchers are integrating genetics, microchemistry, oceanography and computer based mapping to solve the mysteries of how near shore currents link populations, habitats and ecosystems on the regional scale.

"It's ironic that we've known so little about this critical area," said Steve Palumbi of Stanford's Hopkins Marine Station. "We know more about the productivity of the open ocean 1,000 miles off Hawaii, than we do 100 yards off the west coast."

Robert Warner of UC Santa Barbara (Photo courtesy UC Santa Barbara)

The researchers are finding areas of special productivity where fishes and invertebrates concentrate and grow more quickly, and they are beginning to understand why these concentrations exist, providing new insights that apply to coastal management worldwide.

"There's certainly a lot of variation along the coast," observed Hopkins biologist Mark Denny, the John B. and Jean De Nault Professor of Marine Sciences at Stanford. "For instance, if you put little bare plastic or ceramic plates down in the intertidal zone in Oregon and come back a couple of weeks later, the plates are likely to be covered with barnacles."

But when Denny and his colleagues tried the same experiment a few hundred miles south of Oregon along California's Monterey Bay, the results were dramatically different.

Stanford biologist Mark Denny looked at variations in the productivity of barnacles and other species along the U.S. west coast. (Photo courtesy Stanford University)

Historic approaches to managing oceans have focused on individual species or suites of similar species such as salmon or groundfish, because they were prime targets for commercial fishing.

"There is strong consensus that the 'target species' approach is insufficient and there is emerging recognition of the need to switch to ecosystem based management, yet there is precious little understanding of what that actually means," said Lubchenco.

Ecosystem based management will require taking into account the movements of larvae, the importance of preserving individuals and habitats, interactions among species, and how all of those change with larger scale ocean processes such as El Nino and climate change. PISCO scientists are beginning to visualize the spatial and temporal variability of coastal life and to tease apart the differences between human impacts and natural fluctuations.

"We used to think that marine organisms went vast distances when they floated in the sea, but it turns out that that they are not really going that far," said Palumbi. "We're finding that the oceans are not just one big neighborhood but are chopped up into smaller ones. In fact, every bit of coastline might be a small neighborhood that we can manage and try to preserve on its own."

Stanford biologist Stephen Palumbi says future conservation efforts may need to concentrate on particularly productive "neighborhoods." (Photo courtesy Stanford University)

"If we're going to manage the ocean, it's really going to be on a neighborhood by neighborhood basis," Palumbi added. "The very existence of those neighborhoods is a very different way of looking at the ocean than we thought before."

"Ten years ago, the conventional wisdom was that these populations were just one big mix up and down the coast - and that's how fisheries are managed at the state and local level," he explained. "The fact these neighborhoods exist means that it's possible for there to be local benefits, and that's one of the things that will make a big difference in getting local communities to begin protecting chunks of the sea."

Increasing numbers of people are settling along ocean coastlines, bringing rapid changes to these areas and lending urgency to the need to examine human impacts on coastal ecosystems, the AAAS speakers noted.

PISCO researchers are hoping to learn more about how large scale ocean processes like storm driven waves interact with various marine species and their habitats. (Photo courtesy NOAA)

A key question, Warner noted, is where various coastal marine species travel as they grow and disperse.

"These underwater environments are characterized by very complicated ocean processes and by tiny organisms that are drifting in a 'blanket' for weeks or months," he explained. "Eventually, they settle into habitats and replenish populations. But, the real challenge is to describe this dispersal and how coastal communities are put together. When settlement occurs, where do the young come from? We need to know because the current trend is spatial management - that is, drawing lines across the ocean, for zoning purposes."

Innovative new tools, including genetic mapping of marine populations, are revealing that near shore underwater neighborhoods "are a lot smaller and cozier than we ever imagined," Palumbi said.

Thus, "Action taken locally, in a particular area, can have a very strong effect" in protecting near shore marine environments, Warner added.

In the Bahamas, divers from the U.S. National Undersearch Research Program's Caribbean Marine Research Center prepare to drill into a coral reef to study climate over the past 20,000 yrs. (Photo courtesy NOAA)

Palumbi and Warner have written an article that will appear in a forthcoming issue of "Frontiers in Ecology and the Environment," the journal of the Ecological Society of America. The article, "New Tools for Designing Effective Marine Reserves," outlines several research tools that the authors argue will be critical to learning more about the usefulness and impact of one emerging management tool - marine reserves.

Four research methods are helping scientists learn more about the impacts of marine reserves on the ecosystems in which they are imbedded, the authors said. Remote ocean sensing, in real time, over short spatial and temporal scales, is helping scientists chart the dynamics of ocean environments at scales as small as one kilometer, revealing the physical connections between reserve and non-reserve areas.

The chemical signal of trace metals in growing skeletons of key marine species now allows researchers to track where larvae and juveniles drift in the sea. Genetic differences among populations provide a general method for indirect monitoring of species dispersal, both inside and outside reserves.

Shore based radar is used to monitor ocean currents in the Santa Barbara Channel and their effects on the abundance of rockfish larvae. (Image courtesy UC Santa Barbara)

By using such new research tools to open the black box of the near-shore underwater world, scientists hope to better assess the array of conservation options, from marine reserves to large scale restoration. New investigative strategies "help inform management because they describe ecosystem patterns over the spatial and temporal scales that are directly relevant to conservation and ecosystem management," the "Frontiers in Ecology and the Environment" article concludes.

While the new science offers hope that scientists will someday understand how to restore damaged ecosystems, Lubchenco cautions that much research is left to be done.

"We need to acknowledge the reality of uncertainty. Even though we are making great headway in understanding the causes of variability in ocean populations, the complexity and inherent uncertainty of the coastal ecosystem points towards the need to build in buffers," she said. "An example might be designing networks of reserves that can take advantage of variability - protecting a variety of habitats and oceanographic features so that we will be more likely to sustain populations in the long term, through the ups and downs of natural fluctuations - some reserves might be good one year, others next year, some during El Nino years."

In order to restore ecosystems, managers will have to consider all scales, from larvae to the entire ecosystem.

Mark Brzezinski of Oregon State University examines silicon isotopes using mass spectrometry, looking at the relationships between marine phytoplankton known as diatoms and carbon fixation in the ocean. (Photo courtesy UC Santa Barbara)

PISCO is funded by a grant from the David and Lucile Packard Foundation. Supplemental funding for PISCO related research has been provided by the Andrew W. Mellon Foundation, the National Science Foundation, the Office of Naval Research and the National Oceanographic Partnership Program.

For more information about PISCO, visit: http://www.piscoweb.org/