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California’s ongoing population growth and rapid land transformation has long presented a challenge to groups attempting to protect habitats and species, both critical and common. It was the aim of the Natural Reserve System (NRS) founders, in the 1960s and 1970s, to assemble representative samples of all of California’s ecosystems and thus enable research that investigates, along with teaching that communicates, what constitutes a balanced, healthy overall environment. A reserve system is built site by site, but unless an adequate selection strategy, broad in its perspective, is employed, too many reserves may be acquired largely on the basis of opportunity, creating a system insufficiently diverse. The NRS founders targeted specific ecosystems, applying the best scientific, academic, and administrative criteria of the day. Over the last thirty years, however, scientists have honed those criteria, gradually developing an even more rigorous approach to reserve siting, the process of determining where and why a piece of land should become a natural reserve.
Professor Frank Davis and researcher David Stoms, based at UC Santa Barbara’s Biogeography Laboratory, are leaders in the emerging field of reserve design theory. “It’s getting harder and harder to protect biodiversity in an ad hoc way,” Davis observes. “A lot of the land where there are threats to biodiversity also has value for other things, whether it’s agriculture or development. Conservation aimed at protecting species in those areas has gotten contentious and expensive. The challenge is to identify places where you can do conservation planning most cost-effectively, most efficiently, and with the least amount of conflict.” With development pressures bearing down on all sides, stronger measures supported by cutting-edge technology are called for in the effort to protect and appropriately steward natural resources.
Contemporary reserve design theory combines a wide range of disciplines, from geography and conservation biology to land-use planning and economics. And, because almost all conservation decisions are made in the public arena and are often quite controversial, elements of sociology, political science, and the law also factor into the equation. For these reasons, scientists have developed sets of tools and algorithms for evaluating different conservation options. Organizations with straightforward missions, like the UC Natural Reserve System, now use these tools to guide land acquisition. In other, less focused situations — where groups with multiple interests and/or goals are involved — scientists serve as advisors and employ their tools to make all parties aware of possible conservation options. California’s marine reserve science team (described in “Preserving Marine Ecosystems,” page 4) is a perfect example of scientists being called upon to act as advisors in the public arena.
Determining What’s Vulnerable
The first step in reserve design is to conduct a survey of existing reserves to determine their composition, species, ecosystem types, and size. Two questions to be answered are: what elements of biodiversity are already protected across the system? and what elements are in jeopardy? This process, called Gap Analysis, was originally accomplished by overlaying two maps, one showing existing reserves and the other showing the habitats for endangered species. Where the two overlapped, all was well. Where the two failed to overlap, scientists knew it was likely they would eventually have a new goal: to press for additional reserve land or at least corridors to protected land that could serve those species fortunate enough to be self-propelled.
Today more sophisticated Gap Analysis evaluations are carried out on computers, using data from geographic information systems (GIS), satellite-based remote sensors, following the extensive field research needed to locate the distribution of biodiversity elements. Gap Analysis not only identifies species and habitats unprotected by existing reserves, it often suggests possible ways to improve a reserve network’s “coverage.” As Davis explains: “You want sites that are both rich in what you’re looking for and, also, complementary to what you already have. What’s the minimum set of reserves that will cover all those elements? It sounds easy, but in practice it’s a very large computational problem, so much of the work in that area has involved applying algorithms from operations research and decision science. It’s almost become more of an engineering problem.”
Davis and Stoms have been involved in a number of regional gap analysis projects. Beginning in 1990, for example, they worked with various federal, state, and local agencies on the California Gap Analysis Project. Stoms recalls that “our goal was to create statewide databases and then apply them to identify elements, communities, and vertebrate species at risk based upon patterns of land ownership and management.” The California Gap Analysis Project was concluded in 1998; the resource databases it produced have proven valuable in focusing conservation efforts.
A number of modeling techniques have been developed for prioritizing land acquisitions. The simplest is a scoring approach. When the University of California Office of the President asked the UCSB Biogeography Laboratory to evaluate potential reserve sites for its tenth campus, UC Merced,1 Stoms and Davis developed a list of NRS-specific concerns organized under the categories of scientific, academic, and administrative suitability. They then assigned values to potential sites in each category. This scoring approach identified highly suitable potential sites according to the criteria measured by the UC NRS guidelines. Candidate sites would then be evaluated with more specific information. “When assessing the suitability of potential reserve sites over a large region,” Stoms explains, “you never have all the detailed information in maps that you would like. Therefore, you have to go with what you know to narrow the search space. As the search narrows, you generally find information about more of the criteria at higher spatial resolution. Ultimately, when you get down to a few parcels, you can go beyond the maps and fill in the missing data in the field.”
Preserving Genetic Diversity
In addition to coverage — defined as protecting as many vulnerable habitats as possible — any modeling technique must take into account a number of other factors. For example, persistence — the probability that a current condition or set of circumstances will continue into the future at a particular level — has become a major question. As global warming not only continues, but accelerates, what is the likelihood that an endangered species, or the ecosystem that supports it, will soon disappear, anyway? Can the chances of that species disappearing be reduced by protecting its genetic biodiversity? Should individuals from the northern and southern extremes of that species’ range be included in a reserve system in order to protect this biodiversity?
UCLA Professor Victoria Sork teamed up recently with Frank Davis to consider genetic variation in oaks and the extent to which key areas of this habitat-defining genus were being protected, or not protected, in California.2 “Diversity of habitat is important,” explains Sork, “but how do we know we’re not leaving some really important pieces of evolutionary history unprotected? If we’re interested in protecting evolutionary hot spots, the only way we’re going to do that is to look at the genetic history of populations.”
Sork’s genetic markers did in fact identify unprotected areas of high genetic diversity or genetic uniqueness for certain oak species. Her initial findings indicate that areas in the San Francisco Bay Area and at the southern extreme of the oaks’ range might be critical to the future of these Quercus species. “Climate change makes this situation even more crucial,” Sork notes. “If we want to preserve the full range of genetic variation, given that some genotypes adapted to warm climate are going to be in the south, we should make sure we try to preserve those areas. The southern populations have some unique variations that we don’t see in the north. We may want to either preserve those populations or at least keep those acorns around to do restoration.”
A Question of Dollars and Priorities
In the end, economics is often the deciding factor in reserve system design. Sites where the biodiversity is more threatened are often more expensive to protect. The tradeoff often comes down to spending less money to buy less threatened sites versus putting all the available money into more threatened areas, knowing that they will otherwise be lost. As Davis puts it: “Much of conservation planning focuses on reconciling what you know about the geography of threat with what you know about the geography of land markets.”
In areas where people strongly contest the disposition of lands, the scientists’ role is to use conservation planning tools to help all sides see what problems, opportunities, and different priorities might emerge, depending upon how matters are weighed. For example, one group might care more about endangered species or watershed protection, while another cares more about “smart growth”3 and the preservation of agricultural lands. In California — in fact, wherever land planning is carried out — both these groups and many more may appear at the table, so a scientist may be called upon to fulfill a consulting role to help stakeholders understand the consequences of their choices.
Achieving an Integrated Approach
The last, crucial step in the reserve design process is incorporating conservation and design theory into a larger analysis of regional land-use dynamics to produce a more integrated approach to land planning. The Endangered Species Act (ESA) provided the catalyst for much of this effort. “The ESA really changed land planning in California,” says Davis. “In areas with endangered species, you see much more integrated land planning that includes attention to biological concerns. This has led to a number of multispecies conservation programs across the state as part of the Natural Communities Conservation Planning (NCCP) process.4 NCCP provides a legal and institutional framework within which local governments can allow development to proceed, even though there may be endangered species in the planning area, as long as they set aside enough habitat to conserve the species. Today twelve counties are doing large NCCPs that involve a lot of systematic conservation planning that tries to balance habitat conservation with development.”
Though he admits that NCCP is an endgame measure — the species involved are, after all, endangered — Davis sees great value in the process. He says: “It’s an important thing to do. Until recently, land planning has not considered ecosystem resources. We tended to put all of the natural resource management in the hands of one set of public agencies, and the land development process in a completely separate sphere, without any concern for natural resource protection. Today we see, more and more, that you can’t separate the two.”
Preserving Marine Ecosystems
California’s terrestrial landscapes aren’t the only areas under pressure. Its intertidal and near-shore marine environments are also being hit hard by human impacts, especially fishing and pollution. In response to these pressures, the California legislature passed the Marine Life Protection Act in 1999, directing the state Department of Fish and Game to design and manage a network or system of Marine Protected Areas (MPAs). After some trial and error, Fish and Game set up a multilevel process to design the system. Although the Fish and Game Commission makes the final decision, they act on the recommendations of a statute-mandated “Blue Ribbon Task Force,” which in turn takes into account proposals made by a number of stakeholder groups, such as fishermen, conservation groups, educators, and scientists.
Just as they have done with terrestrial systems, scientists are playing a key role in this process to design marine reserves. In fact, they often use the same tools, including software, to perform their gap analyses. Mark Carr, associate professor of ecology and evolutionary biology at UC Santa Cruz, serves on the Department of Fish and Game’s science advisory team. “We didn’t draw the boundaries of specific MPAs,” he explains. “We established the guidelines for the system, and stakeholder groups proposed network packages based on our outline. Then we evaluated each proposal on how well it met the guidelines.”
The scientists’ first step was to examine the full range of biological communities along the entire central California coast, including their diversity, and to identify representative habitats that must be included across the whole system of MPAs. As Carr recounts: “Each plan had to include eight habitats: shallow sand, deep sand, shallow rocky reef, deep rocky reef, canyons, estuaries, kelp forests, and surf grass. We know that the biological communities on rocky reefs differ as a function of depth, so we came up with depth categories that had to be represented. This forced each plan to extend their MPAs offshore to encompass the diversity across that depth gradient.”
Other key scientific guidelines are related to the size, spacing, and number of protected areas, as well as the levels of protection within each MPA. For optimal sizing, the panel looked at fish movement, then offered its recommendation for how large a reserve should be in order to encompass these movements throughout the fishes’ lives.5 Based upon this research, the panel determined that a marine reserve should stretch along the coast for a minimum of 5 to 10 kilometers (3 to 6 miles) and preferably 10 to 20 kilometers (6 to 10 miles).
To determine the optimal spacing between reserves, the group looked at the larval dispersal of different species. Unlike closed terrestrial ecosystems whose populations are replenished by their own young, marine ecosystems rely on the delivery of larvae from other areas for replenishment. After conducting a search of all the available literature on prevailing currents and larval duration (how long larvae remain in a water column6), the panel recommended a network of multiple smaller reserves spaced no more than 50 to 100 kilometers apart to maximize the transfer of larvae from one site to another.
Another factor that had to be considered was the taking of transient species, such as salmon and albacore, that move in and out of the MPAs. This was a critical issue for fishermen. After much discussion, the panel decided that depth was the key. Carr explains: “If you fish for a species like salmon at the surface in waters shallower than 50 meters, there’s a very high likelihood that you’ll catch other things, like rockfish. If you’re in deeper waters — say, 150 meters — and you’re fishing for salmon at 50 meters, there’s a lower likelihood that you’ll impact anything else in the system, so we decided to allow some fishing in the deeper MPAs.”
At first, the progress of establishing system guidelines and evaluating MPA proposals was difficult and contentious, but now it seems to be picking up momentum. The Fish and Game Commission finalized the MPAs around the Channel Islands in 2003. In the fall of 2006, the commission selected a preferred alternative, along with two other alternatives to consider in the regulatory process, for California’s central coast. Next they will look at the north and south coasts. Carr will remain involved in this process, especially as the panel’s attention moves northward, but he also has plans to monitor the MPAs already established: “We’re shifting the ongoing, long-term, large-scale monitoring we were already doing as part of PISCO [Partnership for Interdisciplinary Studies of Coastal Oceans] to new sites to collect baseline information on the new MPAs. To gauge their effectiveness, we’ll need to sample both the protected areas and similar habitats outside of the protected areas over time.”
More and more, reserve design, whether terrestrial or marine, is supported by technology and a broader perspective, yet complicated by controversy. People on all sides have strong vested interests. The likelihood is that these conflicts will become even more heated as time passes. The hope is that science can provide a framework for devising solutions. Frank Davis is philosophical:
We have to do this systematic work now because we’ve protected the stuff that’s easiest to protect — it’s remote, it’s rugged, it’s unproductive. But if we’re really interested in protecting species and ecological communities, [then we must face the fact that] those most in jeopardy are often located where the interests are most in conflict. Every local land planning process in California is very contentious. We hope to bring more systematic information to bear and to help people understand all of the different dimensions of the conservation problem. Science is just part of the process. It can contribute, but it can’t make the ultimate decision. That’s a much more complex social process.
— JB
Endnotes
1Stoms, D. M., J. M. McDonald, and F. W. Davis. 2000. Knowledge-based site suitability assessment for new NRS reserves for the proposed UC Merced campus. Santa Barbara, University of California. PDF available online at: http://www.biogeog.ucsb.edu/pubs/Technical%20Reports/Technical%20Reports.htm.
2Sork, V. L., F. W. Davis, and D. Grivet. 2006. Incorporating Genetic Information into Conservation Planning for California Valley Oak. Presented at the Sixth Symposium of Oak Woodlands, Sonoma, CA, Oct. 9-11, 2006.
3“Smart growth,” a philosophy underlying certain policies governing urban land-use planning and transportation, seeks to benefit communities while preserving the natural environment. Smart-growth proponents advocate: the creation of communities, each of which has a unique sense of identity as a unified body of individuals with common interests living in a particular place; the preservation and enhancement of natural and cultural resources; equitable distribution of both the costs and the benefits of development; expansion of the range of transportation, employment, and housing options; choice of long-range, regional considerations of sustainability over short-term focus; and the promotion of both public health and healthy communities.
4The Natural Communities Conservation Planning (NCCP) program is a cooperative effort run by the California Department of Fish and Game to conserve natural communities at the ecosystem scale while accommodating compatible land use. The program, which began in 1991 under the state’s Natural Community Conservation Planning Act, is broader in its orientation and objectives than the state or federal endangered species acts that protect individual species. Its objective is to anticipate and prevent the controversies and gridlock caused by species’ listings by focusing all key interest groups (government agencies, environmental groups, developers) on the long-term stability of wildlife and plant communities.
5The effort that must be dedicated to collecting information before any analysis can commence or recommendations can be advanced is staggering. Information-gathering is thankless, neverending work, involving both field research and literature searches. And still the amount of data available can be limited. Science panels are criticized at times for not having sufficient data, but they do the best they can with what they have. One of the main reasons the NRS was created was to enable just such efforts, thereby benefiting land-use planning and management in an arena that extends well beyond the 130,000 acres that presently comprise the UC reserve system.
6A water column is a vertical section of the sea. By moving up and down in a water column, larvae are able to catch different currents. Currently, the big question is: to what extent are larvae able to choose which currents they enter and where they end up? In the past, scientists assumed that larvae were mostly just floating, that chance alone determined their ultimate landing places. Now some scientists argue that larvae have more control over their own destinies than was previously thought.
[Sidebar]
The NRS Role in California’s Protected Environments
How do the 130,000+ acres managed by the UC Natural Reserve System figure into the state’s network of protected lands? Although the acreage represented by NRS reserves is relatively small in the context of the entire state’s 101,571,840 acres, UC Santa Barbara Professor Frank Davis feels the reserve system nevertheless plays an important role:
The NRS is interesting because its holdings are in some ways complementary to the holdings of the major land management agencies like the National Park Service and the U.S. Forest Service. Those agencies tend to protect higher elevation montane environments and species, whereas many NRS sites happen to be located on the valley floor or in the foothills. So, in that sense, the NRS is a very important part of the network, because it tends to better represent some of those environments that are often the hardest lands to preserve since they have a lot of other uses like housing, agriculture, and development.
According to UC Santa Cruz Associate Professor Mark Carr, who serves on the California Department of Fish and Game’s scientific advisory panel to help design Marine Protected Areas (MPAs), the NRS also plays a key role in California’s offshore marine reserve system. Though most people think of terrestrial and marine environments as separate entities, there’s a huge interaction between what happens on land and what happens directly offshore in the ocean. The formation of extensive biological “dead zones” in coastal waters as a result of the outflow of nutrients released from agricultural practices is a dramatic example of such land-sea interactions.
Mark Carr worked with Frank Davis and David Stoms to consider land/sea interactions and how they should be taken into account when designing marine protected areas.* “It’s important that you think about what’s happening on land when siting MPAs,” Carr notes. “One of the strongest interactions is through watersheds, so you have to think about the need to protect watersheds if they’re impinging on marine reserves. On the other hand, you don’t want to place an MPA in the path of a watershed that’s been highly perturbed.”
Carr isn’t surprised that two of the state’s larger MPAs on the central coast are located adjacent to NRS coastal reserves: the Landels-Hill Big Creek Reserve in Monterey County and the Kenneth S. Norris Rancho Marino Reserve in San Luis Obispo County. “Big Creek, especially,” he says, “is a perfect example of a watershed that is relatively pristine, and the underwater environment off of Norris Rancho Marino is very rich.”
NRS reserves also provide another crucial element that Carr calls “eyes on the water.” Enforcing the boundaries of and restrictions in many of the new MPAs will require the use of ships and planes; however, the resident managers, stewards, and researchers at NRS sites will provide trained observers for adjacent marine reserves. “People like Kurt Merg (resident manager at Big Creek) and Don Canestro (resident manager at Norris Rancho Marino) are going to be really important,” notes Carr. “Don has been involved throughout this process, serving on the education and research stakeholder group. His work has been invaluable.” —JB
*Stoms, D. M., F. W. Davis, S. J. Andelman, M. H. Carr, S. D. Gaines, B. S. Halpern, R. Hoenicke, S. G. Leibowitz, A. Leydecker, E. MP Madin, H. Tallis, and R. R. Warner. 2005. “Integrated coastal reserve planning: making the land-sea connection.” Frontiers in Ecology and the Environment 3: 429-436.
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