Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 80
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California How Scientific Conclusions Affected NPS Decision Making To address how conclusions based on science affected NPS decision making required the committee to identify decisions made by NPS and infer the role that science may have played in those decisions. The committee identifies the following three explicit decisions: the decision to include a new restriction on boat use in the 2008 Special Use Permit for the commercial shellfish mariculture operation in Drakes Estero; the decision to release Drakes Estero: A Sheltered Wilderness Estuary in its four versions (2006; 2007a; 2007b; 2007c) and subsequent Acknowledgment of Corrections (NPS, 2007e) and Clarification (NPS, 2007d) documents; and the decision to discourage DBOC from seeking a new RUO to continue operations beyond 2012 when the current RUO expires. DECISION TO SIGN THE APRIL 2008 SPECIAL USE PERMIT THROUGH 2012 A Special Use Permit for commercial operations of DBOC within a national park was signed in April 2008. NPS included in the permit a new restriction on boat use by DBOC that directed boat passage away from a more direct deep channel (the “lateral channel”) throughout the year, not just during the harbor seal pupping season. This restriction closes the channel running close to one of the haul-out sites and redirects oyster boat traffic to a more circuitous route over shallower eelgrass beds. This new
OCR for page 81
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California provision may have been motivated by concluding that motorboats pose a high risk of disturbance to the harbor seal, a species protected under the Marine Mammal Protection Act, and that risk is more serious than the increased damage to eelgrass beds from propeller scars. This decision is consistent with the recommended Resource Protection Measures enumerated in the California Coastal Commission’s Consent Order (CCC-07-CD-11, Nov. 29, 2007). By comparison to the year-round closure of the lateral channel to oyster boats, kayak use in Drakes Estero is restricted from March 1 through June 30, “to protect harbor seals from disturbance during the most crucial part of the pupping season,” (available at www.nps.gov/pore/planyourvisit/kayak.htm). DECISION TO WRITE AND RELEASE DRAKES ESTERO: A SHELTERED WILDERNESS ESTUARY PLUS THE ACKNOWLEDGMENT OF CORRECTIONS AND CLARIFICATION DOCUMENTS NPS reported scientific observations and conclusions in all four versions of Drakes Estero: A Sheltered Wilderness Estuary that were released to the public. In that sense, this decision involved science. The degree to which the science motivated the decision to release this report is unclear. The scientific conclusions presented in the report included several that did not match what can be rigorously concluded from the limited scientific studies that have been conducted in Drakes Estero or analogous systems (see above). The scientific information on impacts of oyster culturing at Drakes Estero is limited and provides an insufficient basis on which to address some of the most important concerns about impacts. Based on this committee’s conclusions, the most important concerns relate mostly to activities of the culturists rather than to presence of and activities of the oysters themselves, which is not reflected in the Drakes Estero: A Sheltered Wilderness Estuary. Potential negative effects of activities of the culturists on the harbor seal population represent the most serious concern, which cannot be fully evaluated because these effects have not been directly investigated. The reinterpretations of available science, prompted by stakeholder criticism and aided by solicited and unsolicited expert assessments, and corrections of misstatements of existing information in NPS documents appeared to play roles in motivating NPS to prepare and release the Acknowledgment of Corrections and Clarification documents. DECISION TO DISCOURAGE DBOC FROM SEEKING A NEW RUO The crux of the controversy over Drakes Estero is the pending expiration of the RUO in 2012. The actions taken by Point Reyes National
OCR for page 82
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California Seashore, including the addition of specific language in the Special Use Permit on termination of the lease, the preparation and release of Drakes Estero: A Sheltered Wilderness Estuary, and the denial of a permit for research on whether it would be possible to grow native oysters in the estero, indicate that the NPS decided to discourage DBOC from seeking an extension of the RUO (DOI, 2008). NPS’s actions are consistent with the Department of the Interior’s interpretation of the Wilderness Act and the Point Reyes Wilderness Act of 1976 (Appendix A). The July 2008 Inspector General’s Report of Investigation (DOI, 2008) spoke unambiguously to this issue, noting that the Department of the Interior’s Office of the Solicitor advised Point Reyes National Seashore that the Superintendent does not have the authority to extend the RUO because of the congressional mandate designating Drakes Estero as Potential Wilderness (DOI, 2004; see Appendix A). The Solicitor stated that under the Wilderness Act, NPS is mandated to convert Potential Wilderness to Wilderness status as soon as the nonconforming activity can be removed. Consequently, our committee concludes that this decision on extension of the RUO hinges on the legal interpretation of the legislative mandate rather than a scientific analysis of the impacts of DBOC on the Drakes Estero ecosystem. As such, more scientific study of DBOC operations and Drakes Estero would not necessarily affect National Park Service decisions about the future of oyster farming in the estero. In the past, NPS had incorporated oyster farming into the General Management Plan (National Park Service, 1980; cited in Wechsler, 2004) under the Point Reyes National Seashore objective to preserve aspects of cultural significance. If DBOC is successful in having the RUO extended beyond 2012, a collaborative interpretative center could be established between DBOC and NPS, as had been proposed by the previous owner (Tom Moore, personal communication). Results of scientific research on the role of cultured oysters in the Drakes Estero ecosystem would then be valuable contributions to the center. Collaboration on an interpretive center would be consistent with the purposes of the original RUO “for the purpose of processing and selling wholesale and retail oysters, seafood, and complimentary food items, the interpretation of oyster cultivation to the visiting public, and residential purposes reasonably incidental thereto.…” (DOI, 2004; see Appendix A). Under this scenario, science would be needed to set and adaptively modify permit conditions under the new RUO and to develop exhibits for the interpretative center on the ecological role of oysters as an ecosystem engineer or foundation species in estuarine ecosystems, the history of overexploitation, the challenges of nonnative species, conservation problems, the issue of how changing ecological baselines influences wildlife preservation and habitat restoration, the relationships between mankind and oysters, and the challenges of environmental and cultural sustainability. Activities of oyster culturists
OCR for page 83
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California necessarily have some impact on the ecosystem of Drakes Estero, subject to regulation by multiple management authorities to minimize serious impacts, while perpetuating a cultural history of oyster farming that goes back to the 1930s (Anima, 1990, 1991). Cattle ranching and dairy farming persist within the Point Reyes National Seashore as part of the cultural history of the lands, continuing the historical uses of the land that date back to the time of European colonization of this region of California. Oyster farming as currently practiced has a similar, although shorter, cultural history and heritage with modest impacts (positive and negative) on the ecosystem. The ecological impacts of the oysters themselves replace in part an ecological function that was lost when the native oyster became functionally extinct during the mid 1800s to early 1900s as a consequence of unregulated human exploitation (Kirby, 2004). In addition, efforts to restore a self-sustaining population of native oysters in Drakes Estero could be promoted and supported. Science would play an important role in that restoration planning and implementation. Drakes Estero has been recognized as one of the few locations on the U.S. west coast still environmentally suitable for re-establishment of the native Olympia oyster (Shaw, 1997). RESEARCH NEEDS Although Drakes Estero represents an ideal setting for addressing many scientific questions of basic and applied value, the committee restricts its suggestions for key research problems to those issues that could improve management of valuable natural resources within Drakes Estero. Results of research conducted to address these questions would have importance that stretches far beyond their application to management of Drakes Estero because the questions include important aspects of fundamental science. Research to answer such questions is critically needed in the Point Reyes National Seashore as in all National Parks. The lack of sufficient resources in NPS to support the research required to harmonize the facilitation of public use and enjoyment of the parks with the preservation of environmental and cultural assets is a national problem. The availability of sufficient resources to assess environmental impacts of management alternatives and to fund rigorous scientific review of NPS documents prior to release could have provided sufficient information to avoid over-interpretations and misstatements of science, such as those that appeared in the NPS depictions of oyster farm impacts in the Drakes Estero case. The following research topics are not prioritized, but they address important unanswered questions about the various potential impacts of shellfish mariculture examined by the committee:
OCR for page 84
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California Carrying capacity for suspension-feeding bivalves. An interdisciplinary oceanographic field and modeling study, coupled with empirical field monitoring validation on a recurring basis to account for climatic and other environmental change, is needed to determine how the physical flushing conditions in the estero determine the maximal carrying capacity for oyster biomass so as to avoid over-exploitation of phytoplankton resources shared with other suspension feeders and avoid organic deposition of biodeposits high enough to induce sedimentary anoxia. Eelgrass, benthic invertebrates, and fishes. A more detailed sampling or preferably experimental study is required to test how shellfish mariculture influences benthic invertebrates (including the native oyster), eelgrass, and fishes in Drakes Estero. Population-level research on how eelgrass responds to mariculture and why it is expanding in this estuary and not in many other systems would be useful. Also, more work is needed to understand how eelgrass, open sediment, native shellfish beds, and mariculture operations function as habitats for fish and benthic invertebrates at a landscape scale in the estero and other similar systems. Control of Didemnum vexillum. Further understanding of how to control abundances and reduce the risk of spread of the invasive Didemnum vexillum is urgently needed, not just in Drakes Estero but also worldwide. For Drakes Estero, methods need to be developed for how to dispose of Didemnum after scraping it off racks and oyster shells to prevent it from spreading by fragmentation. The current practice of disposing of scraped-off fragments into the estero increases the risk of spread, perhaps even to eelgrass given recent reports of the colonization of eelgrass blades elsewhere. Disease and parasite research for bivalve mariculture. Further research into controlling diseases potentially spread with transport of shellfish larvae, such as oyster herpes viruses, is important to the mariculture industry broadly and to protecting wild stocks of shellfish in recipient water basins. Oceanographic processes leading to poor shellfish larval survival. Major West Coast shellfish hatcheries are currently suffering catastrophic failures in rearing shellfish larvae that appear to be similar to failures in the survival of native bivalve larvae. Larval survival appears to be affected by major changes over the past 2–3 years in coastal ocean upwelling, which involves lowering the pH (Feeley et al., 2008), or changing the abundance of pathogenic microorganisms. This problem is urgent and will require interdisciplinary studies of natural- and human-induced processes because of its unusual nature and its threat to both wild and cultured shellfish populations over wide areas of the West Coast. Pinniped monitoring program. The coordinated pinniped monitoring program across the San Francisco parks network now provides an important resource providing as yet untapped potential for assessing
OCR for page 85
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California trends in the abundance of harbor seals in Drakes Estero in relation to wider regional trends. However, harbor seal haul-out surveys such as this have limited power to detect trends in abundance. The committee, therefore, recommends that NPS continue this program to provide an adequate time series to assess both colony-specific and regional trends. Targeted, spatially-explicit study of activities of mariculturists and their boats in Drakes Estero. Efforts to explain the changes in abundance and behavior of wildlife populations in relation to natural events and anthropogenic activities also require more robust data on patterns of change. Future assessments of the potential impact of mariculture disturbance in this area would greatly benefit from more detailed data on spatial and temporal changes in the distribution of activities by the oyster farm boats and culturists working around oyster bags and racks. This information could be used to construct a more ecologically realistic footprint of the mariculture activity, including potential interactions at sea and on land. GPS loggers or transmitting systems would allow these data to be collected remotely and the resulting footprint modeled using standard techniques. Results could be used in adaptive management to minimize any demonstrated impacts of mariculture activities. Individual seal and bird behavior and fitness studies. If needed to manage future shellfish mariculture operations in Drakes Estero or in other systems, any assessments of direct impacts to harbor seals and birds would require a more detailed individual-based study using animal tracking devices that will allow an assessment of responses to known disturbances of different origin. However, the conservation benefits of such a study must be carefully balanced against any potential adverse effects resulting from more intrusive research techniques. Alternative oyster culture techniques. In the event of an extension of the RUO for DBOC, research would be needed on oyster culture techniques that form an economically viable alternative to placing culture bags near seal haul-out areas. The goal would be to find methods less disruptive to seals and birds. In addition, research on the viability of establishing a self-sustaining population of Olympia oysters would contribute to the potential restoration of the historic baseline ecosystem in Drakes Estero prior to over-exploitation of native oysters. Socioeconomic impacts of oyster mariculture on visitors to the Point Reyes National Seashore. It would be worthwhile to the development of NPS policy to assess the effects of oyster farming on the recreational, cultural, and aesthetic experiences of visitors to the Point Reyes National Seashore and to the economic value realized by these visitors. A study of this nature could also assess, for example, the potential educational value of constructing an interpretive center around the oyster culturing operations.
OCR for page 86
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California THE ROLE OF SCIENCE IN DECISION MAKING Two lines of argument against continued shellfish mariculture in Drakes Estero have been raised: (1) shellfish mariculture is incompatible with Wilderness status as defined in the U.S. Wilderness Act (P.L. 88-577, Sep. 3, 1964; see Appendix A) and (2) shellfish mariculture should not take place in Drakes Estero because of the risk of adverse ecological effects. Science has more to say about the latter than the former. In 2004, prior to the sale of the Johnson Oyster Company to the current owners, the Department of the Interior’s Office of the Solicitor reviewed the “potential wilderness” status of Drakes Estero and concluded that “the Park Service is mandated by the Wilderness Act, the Point Reyes Wilderness Act and its management policies, to convert Potential Wilderness, i.e. the Johnson Oyster Company tract and adjoining Estero, to Wilderness status as soon as the non-conforming use can be eliminated.” (DOI, 2004; see Appendix A) This congressional mandate provides a legal basis for not extending the RUO to DBOC beyond 2012, as cited in the report of the Department of the Interior’s Office of Inspector General in finding that the Superintendent of Point Reyes National Seashore does not have the authority to extend the RUO beyond 2012 (DOI, 2008). With regard to addressing the risk of ecological effects, NPS’s Management Policies prioritize the protection of natural resources, including circumstances where the available scientific information contains substantial uncertainty: “In cases of uncertainty as to the impacts of activities on park natural resources, the protection of natural resources will predominate” (NPS, 2006c). This policy could be applied to permitting decisions before 2012 as well as providing an environmental rationale for not extending the 40-year term of the RUO that was granted upon the Johnson’s sale of the property to NPS in 1972. After evaluating the limited scientific literature on Drakes Estero and the relevant research from other areas, the committee concludes that there is a lack of strong scientific evidence that shellfish farming has major adverse ecological effects on Drakes Estero at the current (2008–2009) levels of production and under current (2008–2009) operational practices, including compliance with restrictions to protect eelgrass, seals, waterbirds, and other natural resources. Adaptive management could help address effects, if any, that emerge with additional scientific research and monitoring to more fully understand the Drakes Estero ecosystem and the effects of shellfish farming. Importantly from a management perspective, lack of evidence of major adverse effects is not the same as proof of no adverse effects nor is it a guarantee that such effects will not manifest in the future. A more definitive understanding of the adverse or beneficial effects cannot be readily or inexpensively obtained; the complexity of marine ecosystems and responses to ongoing environmental change
OCR for page 87
Shellfish Mariculture in Drakes Estero, Point Reyes National Seashore, California (both natural and anthropogenic) requires substantial time and effort to understand. This situation is not unique to Drakes Estero—uncertainty about effects of human activities on ecosystems is a common feature of most decisions about actions that affect natural resources. The ultimate decision to permit or prohibit a particular activity, such as shellfish farming, in a particular location, such as Drakes Estero, necessarily requires value judgments and tradeoffs that can be informed, but not resolved, by science. Science describes the effects (differences in outcomes) that can be expected with and without shellfish farming in Drakes Estero, the level of uncertainty given current knowledge about these effects, and approaches to assess and balance potential risks and benefits. Because stakeholders may reasonably assign different levels of priority or importance to these effects and outcomes, there is no scientific answer to the question of whether to extend the RUO for shellfish farming. Like other zoning and land use questions, this issue will be resolved by policymakers charged with weighing the conflicting views and priorities of society as part of the decision-making process.