Posted by Brad on November 10, 2002 at 18:23:39:
Statewide marine reserve network should have one aim
By John Krist
November 10, 2002
In the fall of 1997, members of a small group calling itself the Marine Resource Restoration Committee for the Channel Islands gathered in a conference room at the Ventura County Star to preview for the Editorial Board a campaign they planned to unveil publicly a few days later.
What they were proposing sounded radical and, frankly, somewhat hopeless: a large network of no-take zones along the shoreline of all six islands inside the national park, where fishing of all kinds would be prohibited.
That local fisheries were in decline seemed clear from the evidence they presented, which showed a steady decrease in the abundance and diversity of the local commercial catch. That decrease paralleled a decline in the abundance and diversity of species recorded during a long-term habitat monitoring project being carried out near the islands by the National Park Service.
It seemed equally clear, however, that the committee would be in for a long, hard battle. Difficult to reach, Channel Islands National Park is one of the least-visited of all the national parks and, therefore, lacks the large and devotedly protective constituency characteristic of beloved mainland preserves such as Yosemite and Yellowstone. Many of those who do visit the islands make the trip specifically to fish, either recreationally or commercially. The committee -- which included longtime local sport fishing enthusiasts Jim Donlon and Evans Hughes, as well as Gary Davis, senior scientist at Channel Islands National Park -- was proposing that these park visitors be evicted from some of their favorite fishing spots.
What all this suggested was that proponents would find it difficult to muster broad political support in defense of a submarine resource most mainlanders had never seen and could not therefore appreciate. On the other hand, opponents would find it easy to draw crowds of angry charter boat operators, weekend anglers, urchin divers, prawn trawlers, kelp harvesters and squid netters to denounce the proposal. And that's pretty much what happened.
Yet, five years later, that committee's seemingly quixotic dream has become a reality. After numerous public hearings, which often featured ugly shouting matches, and contentious negotiations among scientists, environmental activists and fishing industry representatives, California's Fish and Game Commission voted Oct. 23 to establish no-take zones encompassing 25 percent of the waters within three miles of Anacapa, Santa Cruz, Santa Rosa, San Miguel and Santa Barbara islands.
As expected, the decision was denounced by fishing industry representatives, who continued to argue (as they have for the past five years) that the premise of marine reserves is scientifically unsupported. They dismissed as purely "theoretical" the notion that reserves can serve as sanctuaries where depleted species will reproduce in sufficient numbers to repopulate areas outside the protected zones.
That assertion is false. There are plenty of scientific data demonstrating that marine reserves function in precisely that manner. That large and growing body of research deserves a closer look as the campaign for no-take zones moves now onto a broader stage.
Much has happened since 1997 to tip the political scales and make the Channel Islands closure possible. A year after the local reserve campaign began, state lawmakers passed the Marine Life Management Act, which required the development of science-based fishery management plans and regular evaluations of the status of particular species. In 1999, the National Marine Fisheries Service began collecting data on fisheries under its jurisdiction.
Based in part on the data generated by those processes, state and federal managers have in recent months imposed a series of fishery closures and restrictions to halt continued declines in commercially important species (particularly groundfish) up and down the West Coast.
Two years ago, the Pacific Fishery Management Council -- one of eight regional bodies established by Congress to manage fisheries in federal offshore waters -- endorsed temporary no-take zones as a means of reversing declines in commercially important species. In May 2000, President Clinton issued an executive order requiring federal agencies to "develop, strengthen and expand" a national network of marine refuges.
Two years after the Channel Islands campaign began, the California Legislature gave it even more powerful impetus by passing the Marine Life Protection Act, which directed the state Department of Fish and Game to develop a plan for a network of no-take reserves along the state's entire 1,100-mile coastline. A draft of that plan is due to the Fish and Game Commission by Jan. 1; deadline for the commission to adopt a final plan is Dec. 31, 2003.
Now that the pioneering local effort has succeeded, that broader statewide process takes center stage. Ultimately, it will prove more important to the health of California's nearshore marine ecosystem and to the survival of fishing-dependent businesses than the newly formed network in the Channel Islands because it has the potential to affect nearly every species along the coast as well as nearly every Californian who drops a hook, sets a net or dons mask and flippers hoping to pull something to eat or sell from state waters.
And as that statewide effort enters its final phase next year, likely inaugurating a new round of public battles, it's important to balance allegations of inadequate "theoretical" science against the actual evidence that such reserves work.
By any objective standard, that evidence is abundant.
More and bigger
Last year, Benjamin Halpern of the National Center for Ecological Analysis and Synthesis (a research group based at the University of California at Santa Barbara) published a review of 89 studies conducted at more than 100 marine reserves worldwide. The studies he summarized had measured, among other things, the population density, species diversity and size of organisms inside each reserve, and compared those figures to measurements taken from a reference site -- either the same area before it was protected or an adjacent area outside the reserve boundaries.
The difference was striking. Population densities in the reserves were on average 91 percent higher than at the reference sites, species diversity was 23 percent higher, average organism size was 31 percent larger and total biomass -- the sheer quantity of living organisms -- was 192 percent higher. Halpern's report, initially presented at the American Association for the Advancement of Science's 2001 symposium in San Francisco, was the first comprehensive synthesis of empirical studies regarding marine reserves and it provided strong evidence that populations can rebound quickly once fishing pressure is reduced. The studies found on average that results were significant as little as one to two years after establishment of the reserves.
The data were so compelling that 161 of the world's leading marine scientists signed a consensus statement, issued during the AAAS symposium, concluding that "existing scientific information justifies the immediate application of fully protected marine reserves as a central management tool."
It is not surprising that there would be more fish inside a no-take zone than outside, but boosting populations of marine life only within refuges will do little to achieve the broader goals of restoring imperiled species and ensuring sustainable harvest levels. Modern management efforts have always struggled to find that balance point where commercial, recreational and subsistence fishers could continue to harvest marine life for food and other purposes without endangering the continued existence of the resource base on which they -- and other elements of the marine ecosystem -- depend. Traditional management techniques, relying mainly on quotas, permits and seasons, have failed miserably to prevent one commercially exploited species after another from suffering severe depletion.
Ideally, marine reserves would provide practical benefits to the men and women who rely on the sea to make a living. But for reserves to do that, protected breeding populations would need the ability to repopulate areas outside the reserves, where fishing still would be allowed. Fortunately, additional research suggests this is precisely what will happen.
Homebodies and travelers
Many species of fish spend the first part of their lives in what biologists refer to as a planktonic stage: as tiny, newly hatched larvae, they drift with the currents among other minuscule animals and plants. Although the evidence was extremely thin, fishers and many scientists have long believed that the young of such species drift vast distances before they finally assume adult form, establish home territories and stay put.
If that were the case, marine reserves would be of little use, since the young fish born inside them would quickly drift beyond the protective boundaries and become vulnerable to the same fishing pressures the reserves were intended to offset.
Conversely, if it turned out that planktonic larvae do not disperse at all, the news would be equally grim for reserve proponents, since the species recovering inside a protected area would be unable to repopulate ocean waters outside, where the fish could be caught. Reserves would end up being nothing more than a sort of private undersea aquarium for researchers, of no practical use to those who'd been forced to give up favorite fishing grounds in order to establish the reserves. While that may be defensible on conservation grounds, it is a poor basis on which to base public policy, which must be developed and implemented in a political environment.
Several recent research projects suggest that neither of the extreme postulates regarding larval dispersal is accurate, and that it will be possible to design a network of protected areas that both allow depleted species to recover and commercial and recreational fishers to eventually resume casting their lines and nets.
Scientists two years ago published the results of two studies of reef fish -- one conducted by UCSB researchers on St. Croix in the Caribbean, the other by a team from James Cook University in Australia at that nation's Great Barrier Reef -- found that while many larval fish do travel long distances, between 15 percent and 60 percent end up right back where they were born. Additional findings reported the following year by Harvard University researchers from 11 reefs around Bali in Indonesia found that shrimp likewise are homebodies, traveling only a short distance from their birthplaces despite the region's strong currents.
In areas where marine reserves have been in effect long enough to influence population trends, even the fishing industry recognizes that expanding fish populations spill over into unprotected waters. At reserves in California, Florida, New England, Spain, Belize, New Zealand and other places, observers have witnessed fishing boats congregating just outside the reserve boundaries -- a practice known as "fishing the line" -- because that is where catches are highest.
The challenge in designing marine reserves is taking into account larval dispersal rates and adult movement patterns -- both of which vary from species to species -- so as to strike a balance: large enough to provide protection, small enough to guarantee spillover. The secret, according to a team of UC Davis scientists, is to scatter a string of reserves throughout a region.
Designing a network
Using computer modeling, UC Davis biologist Luis Botsford determined that a sequence of small reserves, encompassing 35 percent of the coastline, maximizes both the protection afforded breeding populations and opportunities for people to catch fish. Some fish will never leave the reserve, forming a reproductive foundation for the population, but others will cross the boundary and be caught. Species that travel still farther will leave the reserve, becoming vulnerable to harvest, but some will travel far enough to reach safety in the next reserve up or down the coast, preventing the population from being depleted by nets and hooks.
It is this modeling, which Botsford presented during last year's AAAS meeting, that has the greatest relevance as the California Fish and Game Commission considers the statewide network of marine protected areas as mandated by the Marine Life Protection Act. As was the case during debate over the reserves at Channel Islands National Park, statewide sport and commercial fishing interests likely will pressure the state to keep reserves small, few in number, or to locate them in economically and politically convenient places -- meaning sites of poor habitat already so devoid of life that nobody goes there to fish anyway.
They also will argue, despite evidence provided by their own catch data, that there's nothing wrong with California's marine fish species, or that if there is, it's because of pollution, El Nino, sea otters -- anything but fishing. Or if it is a result of fishing, it's the fishing that someone else is doing: Sport fishers blame the commercial fleet; commercial fishers blame weekend party boats. They'll argue that existing management strategies are working, despite the emergency closures imposed in recent months to keep once-popular fish off the endangered species list, and will again assert that there's no "sound science" demonstrating that reserves work as advertised.
The assertion rings increasingly hollow. Opponents of the reserve concept may choose to ignore or disbelieve the supporting data, most of which were presented publicly again last month in Santa Barbara during the California and the World Ocean conference, but that is not the same as proving it does not exist.
There are legitimate questions about how the experience in other parts of the world can be replicated along the California coast, but it is impossible to reach conclusions without testing the concept. As part of that test, a sound mechanism must also be established for evaluating the results and adjusting reserve size and boundaries if needed -- always a prudent approach to policy formulation in the face of uncertainty, but also a guarantee to skeptics that if they turn out against all odds to be right, there will be a mechanism in place to rectify the regulators' mistake.
As they move forward with a statewide marine reserve plan, the commissioners must recognize, as they did in approving the Channel Islands proposal, that the scientific data illustrating the effectiveness of marine protected areas are clear and convincing. They must also recognize that a statewide reserve network will only work properly -- preserving fish populations and restoring health to California's beleaguered commercial and sport fisheries -- if it is designed primarily to satisfy ecological needs, not merely political or economic ones.
-- John Krist is a senior reporter and Opinion page columnist for The Star. His e-mail address is firstname.lastname@example.org.
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