Based on simulation studies using historic monitoring data from SF Bay, we propose a monitoring plan with a standardized survey protocol that will provide robust estimates of spatial and temporal changes in shorebird populations in SF Bay. We also present an online data entry portal developed for the California Avian Data Center (CADC) to capture data and provide general summaries from annual monitoring data. We recommend an annual survey of a stratified random sample of locations to be conducted during high tide on a single day. We provide the analytical framework for population and trend estimates to be made annually as new data come in through the online data portal in CADC. Overall, the new survey design is a 66% reduction in effort from previous comprehensive surveys yet will achieve accurate estimates of trend. We also recommend that a comprehensive survey be completed 2 consecutive years every 10 years to determine if the distribution of shorebirds or shorebird habitat has shifted significantly within SF Bay. Large distributional changes could bias inference about trend and habitat associations. We present approaches to modifying the sampling design and analytical approaches to accommodate observed changes. Lastly, we recommend a series of needed pilot studies including evaluating methods for estimating error rates in shorebird counts and determining the appropriate scale to measure habitat and the need for habitat tracking.
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