St.Petersburg Times and Poynter Institute writing instructor, Jeff Klinkenberg, makes much of reporters' often underplaying "place", the "where" in the five Ws of their coverage. When it comes to coverage of marine and oceans issues, Klinkenberg could well have seamounts in mind.

Seamounts? What are they? Asked to quickly conjure up their image of the ocean bottom, many among your readers, viewers, and listeners might think of something along the lines of that initial 20 yards they are familiar with from vacations at the beach, a gently sloping and sandy bottom. They’d be wrong.

If your coverage includes to ocean issues and seamounts aren't on your radar screen, they should be. Seamounts exist as isolated or clustered mountains or hills, and, strictly defined, they can rise 1,000 or more meters from the ocean floor. They are distributed throughout the world's oceans, in many cases, far enough from shore to be in international waters.

Interest in seamounts as important habitats and as far more than just ship-board sonar blips dates back only a half-century or so. Scientific interest in them clearly has increased in the past decade. Scientists have been able to explore only a small fraction of the thousands of seamounts believed to exist worldwide, but they have found many to be rich in biodiversity, containing large numbers of "endemic" fish and invertebrates, meaning they are known to live nowhere else in the world.

Seamounts typically support long-lived, slow-growing creatures extremely vulnerable to disturbance, among them coral communities and some species of fish, such as the orange roughy. Their coral communities have evolved over tens and even hundreds of thousands of years to their present form. Orange roughy can live more than 100 years.

Therein, as they say, lies the rub: Fishing fleets, finding fewer fish to catch in near-shore waters, are venturing farther out into the deep sea. With sophisticated technology, they can locate and fish deep-sea areas such as seamounts. There are ready markets for certain deep-water fish species that make their homes on seamounts, among them orange roughy, alfonsino, and deepwater red fish. Scientists are finding that these new sources of supply, once discovered, are quickly decimated. The early boats on the scene do well, but the law of diminishing returns eventually prevails.

Bottom-trawl fishing practices can be particularly damaging to underwater corals and the thriving bottom-dwelling communities supported by these fragile habitats. Pointing to a study done off the coast of Tasmania, the U.S.-based nonprofit Conservation International is concerned that unfished seamounts may have twice the biomass of fished ones, and only 10 percent bare rock compared to 95 percent bare rock on fished sites. Fishing has been most intense for seamounts that are closest to the sea surface, within 650 to 1,000 meters. There is growing concern among scientists and conservation groups that these habitats, potentially some of the most prolific and diverse on the planet, may be irreparably damaged even before they can be either discovered or studied.

The National Science Foundation and the Census of Marine Life (CoML) program are two organizations working to share scientific data from seamount explorations. They hope to gain new insights about the thousands of unstudied seamounts and determine which unexplored seamounts should be made a priority for study.

The Pew Oceans Commission, in a recently released report on the status of America's oceans, proposes a regulatory approach, a strategy made all the more challenging because most seamounts are in international waters, governed today by a complex array of multinational treaties. In its May 2003 report, America's Living Oceans, Charting a Course for Sea Change, the Pew Oceans Commission called for an immediate ban on the use of mobile bottom fishing gear on seamounts, coral reefs and certain other habitats known to be especially sensitive to disturbance from such gear.

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1  Report on new findings and research results depicting the status of the world's fisheries and related policy recommendations. One report, published in the May 2003 issue of Nature, authored by Ransom A. Myers and Boris Worm of Dalhousie University, reported a global decline of large fish as the result of overfishing and concluded only 10 percent of all large fish, both open-ocean species and large groundfish, are left in the sea. Moreover, says Myers, large fish are not only declining in numbers, but due to intense fishing pressures, may never attain the sizes they once did. Myers in June suggested to the U.S. Senate Commerce, Science and Transportation Committee that the U.S. take the lead internationally to protect marine habitats. Arguing that "unique seamounts are being destroyed for short-term economic gain," Myers recommended a worldwide ban of destructive fishing on all seamounts, particularly those in international waters.

2  Consider doing a series on a particular deep-sea research expedition. Include images of life and environmental conditions at these depths, first-hand accounts from participants, and highlight new scientific findings. While Myers and Worm were publishing their results, the research ship Tangaroa was discovering new species in the Tasman Sea south of Australia. The research ship's findings were consistent with those of earlier explorations. Though Australian and French teams together have sampled fewer than 25 seamounts in the Tasman and Coral Seas, they have discovered new species in unprecedented numbers. Several of these are "living fossils," previously believed to have been extinct since the time of the dinosaurs. In the June 22, 2000, issue of Nature, Bertrand Richer de Forges and colleagues reported that of the 850 species found on seamounts in the Tasman and southeast Coral Seas, 29 to 34 percent were newly discovered. In their article, "Diversity and Endemism of the Benthic Seamount Fauna in the Southwest Pacific," they reported that low species overlap among seamounts in different portions of the region, and highly localized species distributions -- conditions that they say suggest the need for conservation measures to prevent species extinction. Earlier exploration of the Nasca/Sala-y-Gomez chain of seamounts off the coast of western South America had found levels of endemism as high as 51 percent.

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Seamounts, undersea mountains created by tectonic or volcanic forces, are found in all the world's oceans and are more numerous than terrestrial volcanoes. They rise sharply thousands of feet above the sea floor, but unlike islands, they do not break the ocean's surface. They appear singly, in clusters, and in chains called oceanic ridges.

Far more are found in the Pacific than in the Altantic Ocean, because of increased volcanic activity, and seamounts are particularly abundant in the Gulf of Alaska. The Cobb Seamount, part of a chain of seamounts extending from the Gulf of Alaska, has been explored extensively -- largely because it is near the surface and has favorable lighting conditions.

Seamounts come in different sizes and shapes. Some are tectonically active, with hydrothermal vents. Despite differences in height, location, and proximity to landmasses, they tend to be much richer in marine biodiversity than the surrounding waters, so much so that they have been described as "oases" of life in the deep ocean.

The strong ocean currents and steep slopes that are the source of this abundant life also make them difficult subjects to study. Of the tens of thousands of seamounts estimated to be in the Pacific Ocean, only 200 to 250 have been studied. But scientists are making progress with acoustics and submersibles, towing deep-sea video cameras from research vessels and bringing up new findings from their dredges and nets. New analytical techniques are being developed that "mine" existing data to improve understanding of existing deep-sea habitats and to estimate broader biodiversity patterns.

The abundance and diversity of life found on the slopes of seamounts stands in sharp contrast to that of the comparatively barren sea floor. Seamount biological communities are sustained by food carried by passing currents. Nutrient-rich water is deflected upward by their slopes, picking up speed as it rushes over the summit. Close to the summit, thriving communities of suspension feeders, such as corals, sponges and sea fans, filter organic matter from passing water. Orange roughy, for instance, feed on prawns, squid, and small fish that swim by. Sea spiders and lobsters find refuge in the coral and rock outcroppings. Bottom-dwelling animals benefit from nutrients drifting down from the ocean surface above. Whales and tuna visit these undersea mountains on their migratory routes.

Further down the seamount slopes, coral communities become sparse, a phenomenon akin to the treeline in terrestrial mountains but in reverse. Robert Kunzig, author of The Restless Sea, Exploring the World Beneath the Waves, a book about ocean exploration, refers to this phenomenon as the "inverse tree line."

As further explanation for the observed abundance, Kunzig theorizes that the currents may bring more animals to a seamount along with more food. Eddies that swirl above the summit may serve to trap the larvae of animals adapted to the rocky pinnacles of seamounts, "preventing them from being blown away from their place of birth, their island sanctuary, into an unforgiving abyss."

Kunzig points out, however, that not all seamounts follow this pattern. At a seamount 400 miles southwest of Acapulco, scientists in the submersible research vessel Alvin were surprised to find the volcano to be virtually barren at the top. Yet only 70 feet below the summit, dozens of animals could be seen at a glance from Alvin's small portholes. Kunzig writes that the explanation for this is quite simple -- a layer of oxygen-poor water extending downward from the surface and enveloping the summit that is "just about as dead as a polluted lake."

Seamounts often are isolated, which contributes to their unique and diverse ecosystems. Some scientists theorize that seamounts may serve as "stepping stones" for transoceanic species dispersal. "There is a strong parallel with island biogeography, which has a history dating back to Darwin, and a substantial body of knowledge and methodology that we can draw on," says biological oceanographer Karen I. Stocks, University of California at San Diego.

A contrasting view from some studies describes seamounts that have both unique and stable populations. The absence of an external source to "restock" their populations would make seamounts more vulnerable to fishing pressures.

Seamounts vary worldwide in their levels of biodiversity, abundance and endemism. Along with circulating eddies and elevated currents, productivity of the overlying water column and proximity to land masses are among the theories presented to explain these differences.

Scientists have much to learn about the causes of these differences and have just scratched the surface in terms of exploration. "Given what we know from studied seamounts and canyons," said Stocks, "how well can we predict the abundance, diversity, and species composition of communities on the dozens of unstudied canyons and thousands of unstudied seamounts ... and how should future research be targeted to best advance our knowledge?" She is among several marine scientists who are attempting to answer such questions.

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The Census of Marine Life (CoML) initiative is a multi-year international research program seeking to assess and explain the diversity, distribution, and abundance of marine organisms throughout the world's oceans. CoML aims to complete a suite of major oceanic research projects by 2010, concentrating on species diversity and habitat. CoML describes itself as "a growing global network of researchers in more than 45 nations engaged in a 10-year initiative to assess and explain the diversity, distribution, and abundance of marine life in the oceans – past, present, and future."

Ocean Biogeographic Information System (OBIS) (also see: the information component of CoML), provides web-based geo-referenced information on marine species. Sponsors say the effort will provide access to a global network of databases, ocean survey data and ocean environmental data, and species-specific data (taxonomy, specimen, DNA sequence, etc.).

EarthRef.org, "the website for Earth reference data and models," has an online seamount database containing physical information such as bathymetric or depth data.

Pew Oceans Commission Report, America's Living Oceans, Charting and Course for Sea Change. Issued in May 2003, this report outlines a national agenda for protecting and restoring oceans.

The Restless Sea: Exploring the World Beneath The Waves, by Robert Kunzig, W.W. Norton & Company, New York and London, © 1999, 336 pages hardback, ISBN 0-393-04562-5.

Seamountsonline is an NSF-funded website operated by the San Diego Supercomputer Center and part of OBIS, designed specifically to facilitate research on seamount ecology. Contact: Karen Stocks, Ph.D. (858-534-5009 or kstocks@sdsc.edu.

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