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Using Hard Science To Protect Fragile Seas

Date:
July 18, 2001
Source:
Stanford University
Summary:
Marine scientist Fiorenza Micheli has spent more than a decade observing life in the world`s oceans - from the tropical shores of East Africa to the Mediterranean beaches of her native Italy. Yet few sights can match the spectacle she sees from the window of her new office at Stanford`s Hopkins Marine Station overlooking Monterey Bay. Every day, Micheli is greeted by a flotilla of harbor seals, sea otters and sea lions, while flocks of brown pelicans and kittiwakes soar overhead.
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Marine scientist Fiorenza Micheli has spent more than a decade observing life in the world`s oceans - from the tropical shores of East Africa to the Mediterranean beaches of her native Italy. Yet few sights can match the spectacle she sees from the window of her new office at Stanford`s Hopkins Marine Station overlooking Monterey Bay. Every day, Micheli is greeted by a flotilla of harbor seals, sea otters and sea lions, while flocks of brown pelicans and kittiwakes soar overhead.

``Last week I saw two humpback whales swimming right out there,`` she says, pointing toward a white buoy a few hundred yards offshore.

Despite this idyllic scene, Micheli knows that the only way to evaluate the true health of Monterey Bay is to understand the complex web of life below the surface.

``We need to look at marine communities, not just single species,`` she says.

An authority on protecting coastal ecosystems, Micheli left her position at the University of Pisa in January to become an assistant professor of biological sciences at Hopkins Marine Station - Stanford`s 11-acre ocean research laboratory located on the rocky shore of Monterey Bay about 90 miles south of the main campus.

``I was drawn to Monterey Bay because it`s at the cutting edge of research on marine reserves,`` she notes, ``and I`m particularly interested in studying the interactions of the marine communities that live in the bay.``

Human impact

Like many scientists, Micheli is profoundly concerned about the impact of human exploitation on the world`s seas. A recent report by the National Research Council (NRC) estimates that 30 percent of international commercial fish stocks have been depleted below the point where they will be able to produce large yields. In the United States, 80 percent of 191 commercial stocks are believed to be fully exploited or overfished, according to the NRC.

Micheli has documented the dramatic consequence of overfishing and pollution on four continents. In addition to determining the cause of an environmental problem, her research often includes practical solutions that lead scientific, commercial and political interests toward a common goal - restoring fragile ocean habitats.

In 1996, for example, a year after receiving her doctorate from the University of North Carolina-Chapel Hill, Micheli obtained a grant from the North Carolina Division of Marine Fisheries to settle a long-standing dispute between rival oyster and clam fishers. The problem was that each fishery used rakes, tongs or clam dredges that ended up accidentally destroying each other`s potential harvest.

To resolve the conflict, Micheli and her colleagues conducted a one-year study on reefs containing a mix of oysters and clams. The scientists found that clam rakes and oyster tongs reduced the oyster population by 50 to 80 percent, and that raking for clams - either alone or in combination with oyster tonging - decreased the number of clams by 50 to 90 percent. Oyster harvesting alone reduced the population of live clams at only one site.

Writing in the journal Fishery Bulletin, Micheli and co-author Hunter Lenihan concluded that clam and oyster fishing should be allowed on some oyster reefs, but that other reefs should be protected from both types of fishing so that both populations could have the opportunity to reproduce. Such protection would not only restore both fisheries but also have the added benefits of naturally improving water quality through filter feeding and providing new habitats for other species, they wrote.

The findings of Micheli and her co-workers eventually were adopted by state wildlife officials - thus resolving a feud between commercial fishing interests and helping return the shores of North Carolina to sustainability.

Marine reserves

With her experience in North America, Europe, Africa and Australia, Micheli has become a leading voice in the relatively new science of marine reserves.

In February, she and 160 other marine experts signed a Scientific Consensus Statement calling for the establishment of fully protected marine reserves - areas along the U.S. coast that would be off limits to fishing, drilling and other kinds of exploitation. These so-called ``no-take areas`` often are extremely unpopular with local communities, but Micheli`s experience in North Carolina has shown her that commercial and recreational interests can be swayed by solid scientific evidence.

``The declining state of the oceans and the collapse of many fisheries have created a critical need for new and more effective management of marine biodiversity,`` wrote Micheli and her colleagues in the consensus statement. ``At present, less than 1 percent of United States territorial waters, and less than 1 percent of the world`s oceans, are protected in reserves.``

The term ``marine reserve`` is misleading. The United States has a system of federal reserves that includes the Monterey Bay National Marine Sanctuary - a huge section of the Pacific Ocean roughly the size of Connecticut that incorporates some 276 miles of rugged coastline.

The sanctuary is operated by the Department of Commerce`s National Oceanic and Atmospheric Administration (NOAA). According to NOAA`s guidelines, ``Activities that could cause long-term harm to the ocean`s health - like oil drilling - are prohibited. Many others, like fishing and boating, are allowed.``

Commercial fishing interests were instrumental in the establishment of the Monterey Bay marine sanctuary in 1992, but some environmental groups have since called for stricter enforcement of fishing limits.

Urchins, otters and fish

Recent studies have shown that even small no-take zones can significantly increase the size and diversity of marine species, and also encourage the availability of commercially desirable fish to migrate outside the reserve.

``There is significant evidence that fully protected marine reserves are doing what they`re supposed to do, and that they actually can increase fishery yields in adjacent areas,`` Micheli says.

For proof, she need look no further than outside her office window, where she routinely observes sea otters a few yards offshore noisily munching on Pacific sea urchins.

The southern sea otter was hunted to near-extinction by 19th-century Russian fur traders. A tiny population was discovered along California`s remote central coast in the 1930s and has been given complete protection ever since.

Today, the state`s sea otter population has risen above 2,000. As the voracious critters made their comeback, the urchin population rapidly declined. As a result, native kelp forests - no longer threatened by hungry urchins - have returned all along the coast, providing ideal habitat for indigenous crabs, clams, snails and fish.

But protection can have an unexpected downside - especially when the natural ecosystem is totally out of balance. Micheli is evaluating the effects of no-take reserves along the west coast of Italy. Several species of fish targeted by recreational and commercial fishers enjoy eating sea urchins - spiny invertebrates that, in turn, dine on seaweed. A dramatic change in the size of one population can have a cascading effect on the other two species - a phenomenon known as a trophic cascade.

``In the marine reserves of the Medes Islands, Spain, the number and sizes of urchin predators has increased within protected areas, which seems to have resulted in greater predation on the sea urchin population,`` Micheli notes. The subsequent sea urchin decline appears to have resulted in the spread of invasive species of algae that choke off the natural habitat for a variety of native species.

``I am testing this idea of a trophic cascade occurring in the marine reserves of the Tuscan Archipelago, off the western coast of Italy, and possibly influencing the establishment and spread of the invasive `killer` algae Caulerpa,`` Micheli says, adding that she and her colleagues from the University of Pisa hope to continue the long-range research project.

California conflict

Back in California, Micheli finds herself embroiled in another maritime conflict - this one between Hopkins Marine Station and a number of Monterey Bay area residents.

It turns out that, despite the establishment of the Monterey Bay National Marine Sanctuary and other federal and state ocean reserves, only 0.2 percent of California`s thousand-mile coastline is designated as ``no take.`` One of those fully protected areas is the Hopkins Marine Life Refuge located just outside her window. Directly adjacent to the Hopkins reserve is the Pacific Grove Marine Gardens Fish Refuge - a popular stretch of beach known worldwide for its magnificent tide pools.

The state prohibits the taking of marine life from the Pacific Grove refuge, unless one obtains a special permit for scientific gathering. Now a local citizens` group is demanding a complete ban on all collecting - a decision that would affect researchers at Hopkins and at the nearby Monterey Bay Aquarium.

Micheli is hoping for a scientific solution to the controversy. This summer, she and her graduate students will begin a comparative study to assess the impact that tourists and residents are having on tide pool communities.

``I have two goals with this study,`` she notes. ``One is to determine the effect of no-take areas such as the Hopkins Marine Life Refuge on marine populations. The other is to understand the interactions between human disturbances - such as collecting and trampling - and marine invertebrate communities.``

Hopkins Marine Station and the Monterey Bay National Marine Sanctuary offer the ideal setting for conducting that kind of research, Micheli adds.

And the view from her office window is just the icing on the cake.

Relevant Web URLs:

* http://www-marine.stanford.edu/HMSweb/micheli.htm

* http://www.nceas.ucsb.edu

* http://www.mpa.gov

* http://www.sanctuaries.nos.noaa.gov/oms/oms.html


Story Source:

Materials provided by Stanford University. Note: Content may be edited for style and length.


Cite This Page:

Stanford University. "Using Hard Science To Protect Fragile Seas." ScienceDaily. ScienceDaily, 18 July 2001. <www.sciencedaily.com/releases/2001/07/010717081238.htm>.
Stanford University. (2001, July 18). Using Hard Science To Protect Fragile Seas. ScienceDaily. Retrieved March 28, 2024 from www.sciencedaily.com/releases/2001/07/010717081238.htm
Stanford University. "Using Hard Science To Protect Fragile Seas." ScienceDaily. www.sciencedaily.com/releases/2001/07/010717081238.htm (accessed March 28, 2024).

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