Even that fraction of the public that is the least interested in California’s environmental health likely has heard of the delta smelt — the imperiled fish of the upper San Francisco Estuary. The diminutive fish that’s launched way more than its share of controversy. The fish that appears to be inching closer to extinction by the month. 

To be sure, the delta smelt’s numbers are in decline. And the apparent causes are many. The most abundant fishes in the Delta are non-native species that both compete with and prey upon the delta smelt. Contaminants known and unknown poison its waters. Summer-time water temperatures, increasing in real time with climate change, now stress the fish across much of its geographic range. Above all is more than a century of destruction of delta smelt habitat — characterized as reclamation of those landscape areas for the purpose of farming and establishment of now historic communities — and unabated damage to the little that remains. The most impactful in the long legacy of assaults on the delta smelt’s habitat is the loss of the marshlands and wetlands that produce much of the phytoplankton that feed the zooplankton that feed the hungry fish. 


But contributing mightily to the delta smelt’s ongoing decline is not just a daunting list of environmental stressors. It might fairly be argued that prime contributors to the delta smelt’s distressed status are California’s resource agencies. Tasked to protect the delta smelt and its habitat, they have resisted managing the species “adaptively” using widely recognized practices that demand that resource managers take guidance from the best available science and “learn while doing.” The California Department of Fish and Wildlife and increasingly subservient to it in all matters pertaining to protected species, the Department of Water Resources, defiantly refuse to use best professional practices in their efforts to monitor the Bay and Delta’s at-risk fishes — all the while claiming to do so. The agencies persist in mobilizing trawler-based open-water fish surveys, originally intended to census juvenile striped bass, as their primary means of monitoring delta smelt and the Delta’s other protected fish species. The surveys sample neither the relevant habitat strata used by those fishes nor the extent of their “closed” populations, which would allow for estimates of the sizes of their populations. The surveys fail to serve the fundamental purposes of monitoring. 


As a consequence, nearly three decades after the delta smelt was federally protected as a threatened species, neither state nor federal resource agencies can tell us how many delta smelt actually survive in the Delta’s troubled waters, where the fish’s best remaining habitat is located, and what management actions are necessary to reverse its apparent swim toward extinction. Absent targeted monitoring, the resource agencies cannot assess the effectiveness of the various management actions targeting delta smelt that have been undertaken over the past decade. These actions have been implemented at enormous cost in freshwater, a scarce and valuable resource in this time of recurring drought, and many hundreds of millions of dollars yielding no demonstrable benefits to the fish.


So apparent has been the state agencies’ failures to learn from their well-intended management-action agenda that the Independent Science Board (ISB) — the expert science panel advising the Delta Science Program, the Delta Stewardship Council’s scientific watchdog on technical matters in the management of Bay and Delta resources – took on a review of the “monitoring enterprise” in the Bay and Delta in 2018 “to assess long-term monitoring in the Delta to ensure it is responsive to management.” That review, still in draft form, identified more than 150 monitoring programs in the upper San Francisco Estuary, including the Delta and the rivers tributary to it, targeting fishes and other desirable resources. From a polling of experienced participants in resource management in the estuary, the review reported that just 18% of respondents “agreed that the information collected from monitoring serves the needs of decision-makers.” That and other information generated during the investigation led the report’s authors to conclude “Most monitoring programs are not designed to sufficiently answer management questions and have not been designed and/or implemented with the intent of explicitly supporting adaptive management in the Delta.” Labor-intensive and extraordinarily expensive year-round, trawler-based fish surveys are certainly part of that conclusion. Delta fish surveys fail to provide the data and other information necessary to help California meet its promised “coequal goals of a more reliable water supply and protecting, restoring, and enhancing the Delta ecosystem.”


The Collaborative Science and Adaptive Management Plan (CSAMP) is a stakeholder process, wherein state and federal wildlife and water resource agencies, and local water agencies serving a substantial proportion of California’s population. With the release of the draft ISB report, the stakeholders deliberate on the pressing matters of water supply and wildlife management, simply couldn’t continue to ignore the absence of actionable monitoring and a long-promised adaptive management regime. Over two October days and six workshop hours CSAMP provided a forum during which the ISB presented its critical assessment of the Delta “monitoring enterprise.” The government agencies responsible for monitoring were supposed to review their monitoring efforts, past and present, and set them in the context of the ISB’s troubling findings.


Will that forum mark the beginning of the end for expensive, wasteful, and ill-designed data collection in the estuary and the start of an overdue science-based program of management actions attended by monitoring designed to assess its performance? It seems not. Instructed to address the ISB’s findings, presenters for the resource agencies largely skipped reference to the panel’s conclusions and instead defended their fish surveying business as usual. Workshop exchanges suggest that the state agencies and the Interagency Ecological Program intend to minimize and side-step the ISB critique and rebuff the independent expert advice. Instead of confronting the daunting new-millennium conservation challenge in the Delta using incisive science-based management and monitoring practices, it appears that the state’s resource agencies are inclined to stick with a 1970s make-it-up-as-you-go resource management agenda and eschew a fresh look at monitoring that might reveal its shortcomings and improve its value.


The nearly complete absence of information on the performance of directed management actions that have been implemented to benefit delta smelt means lost opportunities for resource managers who otherwise could be able to prioritize successful management actions, adjust and enhance less successful actions, and retire actions that fail to deliver more of the fish. Wedded to fish surveys that haven’t and seemingly can’t produce the information that is needed to inform resource management, California Department of Fish and Wildlife continues to adhere to outdated data-collection efforts producing negligible returns that hinder resource managers in making sound decisions. That status quo comes at great cost to Californians — apparently more than a hundred million dollars a year in fish surveys and the staffing that manages them — and incalculable cost to the delta smelt and other desired species struggling to survive in a manifestly hostile upper San Francisco Estuary.


Employing best professional practices in resource management requires that inquisitive agency staff and administrators embrace constant revision of their conservation plans and data collection schemes and seek guidance from technical experts from beyond their home offices. Designing monitoring for imperiled species has an obligatory first step that must be frequently revisited – clearly identifying monitoring objectives by linking them to unresolved management questions. Data collection is merely an end in itself if it (a) is pursued without a clear connection between monitoring design and a decision structure informed by management objectives, (b) does not acknowledge the uncertainties about how a species and its habitat will respond to targeted management actions, and (c) lacks the potential for monitoring information to improve management outcomes. Regrettably, the standing fish surveys have missed the objectives-setting step for delta smelt and the other listed Delta fishes. Ongoing data collection without that missing step cannot logically inform decision-making under the state and federal Endangered Species Acts. 


Given the ISB’s findings and conclusions, there can be little question that the existing fish surveys are not sufficient to support conservation efforts necessary to save the Delta’s imperiled species. The time is now for the state’s resource agencies to buck up and sincerely embrace adaptive resource management and the rigorously designed monitoring schemes it requires to function effectively.

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