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Grossinger, R. M. 2005. Documenting Local Landscape Change: The Bay Area Historical Ecology Project. In The HISTORICAL ECOLOGY HANDBOOK: A Restorationist's Guide to Reference Ecosystems. Egan, D., Howell, E. A., Trans.. The HISTORICAL ECOLOGY HANDBOOK: A Restorationist's Guide to Reference Ecosystems. Island Press.
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Grosso, C.; Lowe, S.; Pearce, S.; O'Connor, K.; Teunis, L.; Stein, E. D.; Siu, J.; Scianni, M. 2023. WRAMP Training and Outreach Plan. SFEI Contribution No. 1136. p 39.

The goal of this Training and Outreach Plan is to increase the overall awareness and use  of the WRAMP datasets and tools in support of wetland resource planning,  management, and project performance tracking in California. Specifically, a near-term  goal is to develop modular training sessions that can be linked together in different  ways to customize how the datasets, monitoring methods, and online tools might be  used for different purposes. 

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Grosso, C.; Hale, A.; Williams, M.; May, M. 2014. Online 401: From Pilot to Production. San Francisco Estuary Institute: Richmond, CA.
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Gunther, A. J. 1988. The Bioavailability of Toxic Contaminants in the San Francisco Bay-Delta: Proceedings of a Two-Day Seminar Series. SFEI Contribution No. 142. San Francisco Bay - Delta Aquatic Habitat Institute, Richmond, CA: Berkeley, CA.
Gunther, A. J.; Davis, J. A. 1998. An evaluation of bioaccumulation monitoring with transplanted bivalves in the RMP. SFEI Contribution No. 322. San Francisco Estuary Institute: Richmond, CA. pp 187-200.
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Gunther, A. J.; Phillips, D. J. H.; Davis, J. A. 1987. An Assesssment of the Loading of Toxic Contaminants to the San Francisco Bay-Delta. SFEI Contribution No. 137. San Francisco Estuary Institute: Richmond. p 330.
Gunther, A. J. 1987. The Segmentation of the San Francisco Bay/Delta. SFEI Contribution No. 135. San Francisco Estuary Institute: Richmond, CA. p 18.
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Gunther, A.; Thompson, B. 2004. Development of Environmental Indicators of the Condition of San Francisco Estuary. SFEI Contribution No. 113. San Francisco Estuary Institute: Oakland.
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Gunther, A. J.; Blanchard, C.; Gardels, K. 1991. The Loading of Toxic Contaminants to the San Francisco Bay -Delta in Urban Runoff. SFEI Contribution No. 167. San Francisco Estuary Institue: Richmond, CA. p 82.
Gunther, A. J.; Ogle, S. R. 2000. San Francisco Bay Episodic Toxicity Report:1999 Progress Report. SFEI Contribution No. 346. San Francisco Estuary Institute: Richmond, CA.
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Gunther, A. J.; O'Connor, J. M.; Davis, J. A. 1992. Priority pollutant loads from effluent discharges to the San Francisco Estuary. Water Environment Research 64, 134-140 . SFEI Contribution No. 171.
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Hagerty, S.; Spotswood, E.; McKnight, K.; Grossinger, R. M. 2019. Urban Ecological Planning Guide for Santa Clara Valley. SFEI Contribution No. 941. San Francisco Estuary Institute: Richmond, CA.

This document provides some of the scientific foundation needed to guide planning for urban biodiversity in the Santa Clara Valley region, grounded in an understanding of landscape history, urban ecology and local setting. It can be used to envision the ecological potential for individual urban greening projects, and to guide their siting, design and implementation. It also can be used to guide coordination of projects across the landscape, with the cooperation of a group of stakeholders (such as multiple agencies, cities and counties). Users of this report may include a wide range of entities, such as local nonprofits, public agencies, city planners, and applicants to the Open Space Authority’s Urban Open Space Grant Program.
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Hale, T.; Sim, L.; McKee, L. J. 2018. GreenPlan-IT Tracker.

This technical memo describes the purpose, functions, and structure associated with the newest addition to the GreenPlan-IT Toolset, the GreenPlan-IT Tracker. It also shares the opportunities for further enhancement and how the tool can operate in concert with existing resources. Furthermore, this memo describes a licensing plan that would permit municipalities to use the tool in an ongoing way that scales to their needs. The memo concludes with a provisional roadmap for the development of future features and technical details describing the tool’s platform and data structures.

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Hale, T.; Azimi-Gaylon, S.; Fong, S.; Goodwin, P.; Isaac, G.; Osti, A.; Shilling, F.; Slawecki, T.; Steinberg, S.; Tompkins, M.; et al. 2015. Enhancing the Vision for Managing California's Environmental Information. SFEI Contribution No. 792. Delta Stewardship Council: Sacramento, CA.

The Environmental Data Summit, convened under the auspices of the Delta Stewardship Council’s Delta Science Program in June 2014, witnessed remarkable participation from experts across California, the nation, and even the world. Summit attendees from the public, private, federal, and non-profit sectors shared their views regarding the urgent needs and proposed solutions for California’s data-sharing and data-integration challenges, especially pertaining to the subject of environmental resource management in the era of “big data.” After all, this is a time when our data sources are growing in number, size, and complexity. Yet our ability to manage and analyze such data in service of effective decision-making lags far behind our demonstrated needs.

In its review of the sustainability of water and environmental management in the California Bay-Delta, the National Research Council (NRC) found that “only a synthetic, integrated, analytical approach to understanding the effects of suites of environmental factors (stressors) on the ecosystem and its components is likely to provide important insights that can lead to enhancement of the Delta and its species” (National Research Council 2012). The present “silos of data” have resulted in separate and compartmentalized science, impeding our ability to make informed decisions. While resolving data integration challenges will not, by itself, produce better science or better natural resource outcomes, progress in this area will provide a strong foundation for decision-making. Various mandates ranging from the California Water Action Plan to the President’s executive order demanding federal open data policies demonstrate the consensus on the merits of modern data sharing at the scale and function needed to meet today’s challenges.

This white paper emerges from the Summit as an instrument to help identify such opportunities to enhance California’s cross-jurisdictional data management. As a resource to policymakers, agency leadership, data managers, and others, this paper articulates some key challenges as well as proven solutions that, with careful and thoughtful coordination, can be implemented to overcome those obstacles. Primarily featured are tools that complement the State’s current investments in technology, recognizing that success depends upon broad and motivated participation from all levels of the public agency domain. Executive Summary

This document describes examples, practices, and recommendations that focus on California’s Delta as an opportune example likely to yield meaningful initial results in the face of pressing challenges. Once proven in the Delta, however, this paper’s recommended innovations would conceivably be applied statewide in subsequent phases.

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Hale, T.; Grosso, C. 2016. An Introduction to EcoAtlas: Applied Aquatic Science. San Francisco Estuary Institute: Richmond, CA. p 16 pages.

This memo was developed by SFEI to introduce the EcoAtlas tools, their intended (target) user community, and the short- and long-term intended applications. 

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Hale, T.; Grosso, C. 2017. Applied Aquatic Science: A Business Plan for EcoAtlas. San Francisco Estuary Institue: Richmond, CA.

The following plan is intended to ensure the continued vitality of the toolset. The plan’s success will depend upon the continued collaboration of the public agencies that have supported the toolset thus far, but it must also integrate principles of resilience as it accounts for the tensions that arise as organizations move in different strategic directions.

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Hampton, L. M. Thornto; De Frond, H.; Hermabessiere, L.; Miller, E.; de Ruijter, V. N.; Faltynkova, A.; Kotar, S.; Monclús, L.; Siddiqui, S.; Völker, J.; et al. 2022. A living tool for the continued exploration of microplastic toxicity. Microplastics and Nanoplastics 2 (13).

Throughout the past decade, many studies have reported adverse effects in biota following microplastic exposure. Yet, the field is still emerging as the current understanding of microplastic toxicity is limited. At the same time, recent legislative mandates have required environmental regulators to devise strategies to mitigate microplastic pollution and develop health-based thresholds for the protection of human and ecosystem health. The current publication rate also presents a unique challenge as scientists, environmental managers, and other communities may find it difficult to keep up with microplastic research as it rapidly evolves. At present, there is no tool that compiles and synthesizes the data from these studies to allow for visualization, interpretation, or analysis. Here, we present the Toxicity of Microplastics Explorer (ToMEx), an open access database and open source accompanying R Shiny web application that enables users to upload, search, visualize, and analyze microplastic toxicity data. Though ToMEx was originally created to facilitate the development of health-based thresholds to support California legislations, maintaining the database by the greater scientific community will be invaluable to furthering research and informing policies globally. The database and web applications may be accessed at https://microplastics.sccwrp.org/.

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Hampton, L. M. Thornto; Bouwmeester, H.; Brander, S. M.; Coffin, S.; Cole, M.; Hermabessiere, L.; Mehinto, A. C.; Miller, E.; Rochman, C. M.; Weisberg, S. B. 2022. Research recommendations to better understand the potential health impacts of microplastics to humans and aquatic ecosystems. Microplastics and Nanoplastics 2 (18).

To assess the potential risk of microplastic exposure to humans and aquatic ecosystems, reliable toxicity data is needed. This includes a more complete foundational understanding of microplastic toxicity and better characterization of the hazards they may present. To expand this understanding, an international group of experts was convened in 2020–2021 to identify critical thresholds at which microplastics found in drinking and ambient waters present a health risk to humans and aquatic organisms. However, their findings were limited by notable data gaps in the literature. Here, we identify those shortcomings and describe four categories of research recommendations needed to address them: 1) adequate particle characterization and selection for toxicity testing; 2) appropriate experimental study designs that allow for the derivation of dose-response curves; 3) establishment of adverse outcome pathways for microplastics; and 4) a clearer understanding of microplastic exposure, particularly for human health. By addressing these four data gaps, researchers will gain a better understanding of the key drivers of microplastic toxicity and the concentrations at which adverse effects may occur, allowing a better understanding of the potential risk that microplastics exposure might pose to human and aquatic ecosystems.

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Hatje, V.; Bruland, K. W.; A. Flegal, R. 2016. Increases in Anthropogenic Gadolinium Anomalies and Rare Earth Element Concentrations in San Francisco Bay over a 20 Year Record. Environ. Sci. Technol. 50 (8).

We evaluated both the spatial distribution of gadolinium (Gd) and other rare earth elements (REE) in surface waters collected in a transect of San Francisco Bay (SFB) and their temporal variations within the Bay over two decades. The REE were preconcentrated using the NOBIAS PA-1 resin prior to analysis by high-resolution inductively coupled plasma mass spectrometry. Measurements revealed a temporal increase in the Gd anomaly in SFB from the early 1990s to the present. The highest Gd anomalies were observed in the southern reach of SFB, which is surrounded by several hospitals and research centers that use Gd-based contrast agents for magnetic resonance imaging. Recent increases in that usage presumably contributed to the order of magnitude increase in anthropogenic Gd concentrations in SFB, from 8.27 to 112 pmol kg–1 over the past two decades, and reach the northeast Pacific coastal waters. These measurements (i) show that “exotic” trace elements used in new high-tech applications, such as Gd, are emerging contaminants in San Francisco Bay and that anthropogenic Gd concentrations increased substantially over a 20 year period; (ii) substantiate proposals that REE may be used as tracers of wastewater discharges and hydrological processes; and (iii) suggest that new public policies and the development of more effective treatment technologies may be necessary to control sources and minimize future contamination by REE that are critical for the development of new technologies, which now overwhelm natural REE anomalies.

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Heberger, M.; Sutton, R.; Buzby, N.; Sun, J.; Lin, D.; Mendez, M.; Hladik, M.; Orlando, J.; Sanders, C.; Furlong, E. 2020. Current-Use Pesticides, Fragrance Ingredients, and Other Emerging Contaminants in San Francisco Bay Margin Sediment and Water. SFEI Contribution No. 934. San Francisco Estuary Institute: Richmond, CA.

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) has recently focused attention on better characterization of contaminants in nearshore “margin” areas of San Francisco Bay. The margins of the Lower South Bay are mudflats and shallow regions that receive direct discharges of stormwater and wastewater; as a result, they may have higher levels of urban contaminants than the open Bay. In the summer of 2017, the RMP collected samples of margin
sediment in the South and Lower South Bay for analysis of legacy contaminants. The study described here leveraged that sampling effort by adding monitoring of sediment and water for two additional sets of emerging contaminants: 1) current-use pesticides; and 2) fragrance ingredients including the polycyclic musk galaxolide, as well as a range of other commonly detected emerging contaminants linked to toxicity concerns such as endocrine disruption.

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Hoenicke, R.; Tsai, P.; Hansen, E.; Lee, K. 2001. San Francisco Bay Atmospheric Deposition Pilot Study Part 2: Trace Metals. SFEI Contribution No. 73. San Francisco Estuary Institute: Richmond, CA.
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Hoenicke, R.; Hayworth, J. 2005. A Watershed Monitoring Strategy for Napa County. SFEI Contribution No. 428. San Francisco Estuary Institute: Napa,. p 34.
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Hoenicke, R.; Tsai, P. 2001. San Francisco Bay Atmospheric Deposition Pilot Study Part 1: Mercury. SFEI Contribution No. 72. San Francisco Estuary Institute: Richmond, CA.
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Hoenicke, R.; Bleier, C. 2007. Watershed Management and Land Use. CCMP Implementation Committee.
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Hoenicke, R.; Tucker, D.; Tsai, P.; Hansen, E.; Lee, K.; Yee, D. 2002. Atmospheric Deposition of Trace Metals in San Francisco Bay. SFEI Contribution No. 278. San Francisco Estuary Institute: Richmond, CA.
Hoenicke, R.; Tsai, P.; Bamford, H. A.; Baker, J.; Yee, D. 2002. Atmospheric Concentrations and Fluxes of Organic Compounds in the Northern San Francisco Estuary. Environmental Science and Technology 36 (22), 4741-4747 . SFEI Contribution No. 474.
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Hoenicke, R.; Leatherbarrow, J. E. 2000. The Estuary Interface Pilot Study: 1998 Progress Report. SFEI Contribution No. 49. San Francisco Estuary Institute.
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Hoenicke, R. 1997. Creating data-quality objectives: A case study. Water Environment Laboratory Solutions 7-9 . SFEI Contribution No. 31.
Holleman, R.; MacVean, L.; Mckibben, M.; Sylvester, Z.; Wren, I.; Senn, D. 2017. Nutrient Management Strategy Science Program. SFEI Contribution No. 879. San Francisco Estuary Institute: Richmond, CA.
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Holleman, R.; Nuss, E.; Senn, D. 2017. San Francisco Bay Interim Model Validation Report. SFEI Contribution No. 850. San Francisco Estuary Institute: Richmond, CA.
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Houtz, E. F.; Sutton, R.; Park, J. - S.; Sedlak, M. 2016. Poly- and perfluoroalkyl substances in wastewater: Significance of unknown precursors, manufacturing shifts, and likely AFFF impacts. Water Research . SFEI Contribution No. 780.

In late 2014, wastewater effluent samples were collected from eight treatment plants that discharge to San Francisco (SF) Bay in order to assess poly- and perfluoroalkyl substances (PFASs) currently released from municipal and industrial sources. In addition to direct measurement of twenty specific PFAS analytes, the total concentration of perfluoroalkyl acid (PFAA) precursors was also indirectly measured by adapting a previously developed oxidation assay. Effluent from six municipal treatment plants contained similar amounts of total PFASs, with highest median concentrations of PFHxA (24 ng/L), followed by PFOA (23 ng/L), PFBA (19 ng/L), and PFOS (15 ng/L). Compared to SF Bay municipal wastewater samples collected in 2009, the short chain perfluorinated carboxylates PFBA and PFHxA rose significantly in concentration. Effluent samples from two treatment plants contained much higher levels of PFASs: over two samplings, wastewater from one municipal plant contained an average of 420 ng/L PFOS and wastewater from an airport industrial treatment plant contained 560 ng/L PFOS, 390 ng/L 6:2 FtS, 570 ng/L PFPeA, and 500 ng/L PFHxA. The elevated levels observed in effluent samples from these two plants are likely related to aqueous film forming foam (AFFF) sources impacting their influent; PFASs attributable to both current use and discontinued AFFF formulations were observed. Indirectly measured PFAA precursor compounds accounted for 33%–63% of the total molar concentration of PFASs across all effluent samples and the PFAA precursors indicated by the oxidation assay were predominately short-chained. PFAS levels in SF Bay effluent samples reflect the manufacturing shifts towards shorter chained PFASs while also demonstrating significant impacts from localized usage of AFFF.

H. T. Harvey & Associates. 2023. Sycamore Alluvial Woodland Pilot Study Implementation Guidelines. Prepared for Zone 7 Water Agency and US Environmental Protection Agency’s Water Quality Improvement Fund. In collaboration with San Francisco Estuary Institute.

This document supports planting-based approaches for sycamore enhancement by providing site-level revegetation techniques for installing, maintaining and monitoring sycamore plantings.

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Hung, C.; Klasios, N.; Zhu, X.; Sedlak, M.; Sutton, R. 2020. Methods Matter: Methods for Sampling Microplastic and Other Anthropogenic Particles and Their Implications for Monitoring and Ecological Risk Assessment. Integrated Environmental Assessment and Management 16 (6) . SFEI Contribution No. 1014.

To inform mitigation strategies and understand how microplastics affect wildlife, research is focused on understanding the sources, pathways, and occurrence of microplastics in the environment and in wildlife. Microplastics research entails counting and characterizing microplastics in nature, which is a labor‐intensive process, particularly given the range of particle sizes and morphologies present within this diverse class of contaminants. Thus, it is crucial to determine appropriate sampling methods that best capture the types and quantities of microplastics relevant to inform the questions and objectives at hand. It is also critical to follow protocols with strict quality assurance and quality control (QA/QC) measures so that results reflect accurate estimates of microplastic contamination. Here, we assess different sampling procedures and QA/QC strategies to inform best practices for future environmental monitoring and assessments of exposure. We compare microplastic abundance and characteristics in surface‐water samples collected using different methods (i.e., manta and bulk water) at the same sites, as well as duplicate samples for each method taken at the same site and approximate time. Samples were collected from 9 sampling sites within San Francisco Bay, California, USA, using 3 different sampling methods: 1) manta trawl (manta), 2) 1‐L grab (grab), and 3) 10‐L bulk water filtered in situ (pump). Bulk water sampling methods (both grab and pump) captured more microplastics within the smaller size range (<335 μm), most of which were fibers. Manta samples captured a greater diversity of morphologies but underestimated smaller‐sized particles. Inspection of pump samples revealed high numbers of particles from procedural contamination, stressing the need for robust QA/QC, including sampling and analyzing laboratory blanks, field blanks, and duplicates. Choosing the appropriate sampling method, combined with rigorous, standardized QA/QC practices, is essential for the future of microplastics research in marine and freshwater ecosystems.

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Hunt, J.; Trowbridge, P.; Yee, D.; Franz, A.; Davis, J. 2016. Sampling and Analysis Plan for 2016 RMP Status and Trends Bird Egg Monitoring. SFEI Contribution No. 827. San Francisco Estuary Institute: Richmond, CA. p 31 pp.
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Iknayan, K.; Heath, S.; Terrill, S. B.; Wenny, D. G.; Panlasigui, S.; Wang, Y.; Beller, E. E.; Spotswood, E. 2024. Patterns in bird and pollinator occupancy and richness in a mosaic of urban office parks across scales and seasons. Ecology and Evolution 14 (3).

Urbanization is a leading cause of global biodiversity loss, yet cities can provide resources required by many species throughout the year. In recognition of this, cities around the world are adopting strategies to increase biodiversity. These efforts would benefit from a robust understanding of how natural and enhanced features in urbanized areas influence various taxa. We explored seasonal and spatial patterns in occupancy and taxonomic richness of birds and pollinators among office parks in Santa Clara County, California, USA, where natural features and commercial landscaping have generated variation in conditions across scales. We surveyed birds and insect pollinators, estimated multi-species occupancy and species richness, and found that spatial scale (local, neighborhood, and landscape scale), season, and urban sensitivity were all important for understanding how communities occupied sites. Features at the landscape (distance to streams or baylands) and local scale (tree canopy, shrub, or impervious cover) were the strongest predictors of avian occupancy in all seasons. Pollinator richness was influenced by local tree canopy and impervious cover in spring, and distance to baylands in early and late summer. We then predicted the relative contributions of different spatial scales to annual bird species richness by simulating “good” and “poor” quality sites based on influential covariates returned by the previous models. Shifting from poor to good quality conditions locally increased annual avian richness by up to 6.8 species with no predicted effect on the quality of the neighborhood. Conversely, sites of poor local and neighborhood scale quality in good-quality landscapes were predicted to harbor 11.5 more species than sites of good local- and neighborhood-scale quality in poor-quality landscapes. Finally, more urban-sensitive bird species were gained at good quality sites relative to urban tolerant species, suggesting that urban natural features at the local and landscape scales disproportionately benefited them.

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Iknayan, K.; Wheeler, M.; Safran, S. M.; Young, J. S.; Spotswood, E. 2021. What makes urban parks good for California quail? Evaluating park suitability, species persistence, and the potential for reintroduction into a large urban national park. Journal of Applied Ecology.

  1. Preserving and restoring wildlife in urban areas benefits both urban ecosystems and the well-being of urban residents. While urban wildlife conservation is a rapidly developing field, the majority of conservation research has been performed in wildland areas. Understanding the applicability of wildland science to urban populations and the relative importance of factors limiting species persistence are of critical importance to identifying prescriptive management strategies for restoring wildlife to urban parks.
  2. We evaluated how habitat fragmentation, habitat quality and mortality threats influence species occupancy and persistence in urban parks. We chose California quail Callipepla californica as a representative species with potential to respond to urban conservation. We used publicly available eBird data to construct occupancy models of quail in urban parks across their native range, and present an application using focal parks interested in exploring quail reintroduction.
  3. Urban parks had a 0.23 ± 0.02 probability of quail occupancy, with greater occupancy in larger parks that were less isolated from potential source populations, had higher shrub cover and had lower impervious cover. Less isolated parks had higher colonization rates, while larger parks had lower extinction rates. These results align with findings across urban ecology showing greater biodiversity in larger and more highly connected habitat patches.
  4. A case study highlighted that interventions to increase effective park size and improve connectivity would be most influential for two highly urban focal parks, while changes to internal land cover would have a relatively small impact. Low joint extinction probability in the parks (0.010 ± 0.013) indicated reintroduced populations could persist for some time.
  5. Synthesis and applications. We show how eBird data can be harnessed to evaluate the responsiveness of wildlife to urban parks of variable size, connectivity and habitat quality, highlighting what management actions are most needed. Using California quail as an example, we found park size, park isolation and presence of coyotes are all important drivers of whether quail can colonize and persist in parks. Our results suggest reintroducing quail to parks could be successful provided parks are large enough to support quail, and management actions are taken to enhance regional connectivity or periodic assisted colonization is used to supplement local populations.
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