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People in coastal cities around the world harvest seafood from local bays despite well-documented health risks. In cities such as San Diego, California, USA, much information about contaminants and human consumption patterns exists for finfish but is largely lacking for shellfish. This study sought to better understand shellfish contamination risks and human vulnerability to inform management and advisories. In summer 2018 and winter 2019, we sampled crustaceans for chemical contaminants and anthropogenic debris and throughout the year surveyed people harvesting from three public fishing piers around San Diego Bay. Of the emerging contaminants found, pyrethroids, benzylbutyl phthalate, PFOS and anthropogenic debris were in differing concentrations in the muscle and viscera of the California spiny lobster and two species of crabs. Combined with previous metal and organic contaminant data from the lobster, 22 contaminants were detected with 5 exceeding consumption thresholds and 8 lacking defined thresholds. California spiny lobster was the main crustacean harvested from piers, attracting shellfishers from a range of ages, incomes, home locations and self-identified racial/ethnic groups. Consumption preferences (e.g., muscle or viscera) were non-discriminant, making lobster contamination a community-wide risk. More monitoring of emerging contaminants and different shellfish species (and tissues) of interest is recommended to capture the spatial and temporal dynamics of health risks, especially because the use of bivalves as sentinels may not reveal the same risks (e.g., PFAS, phosphate flame retardants). [ABSTRACT FROM AUTHOR]

High severity fire is far outpacing post-fire reforestation capacity across the American West, highlighting the need to better understand when and where natural regeneration is sufficient to meet short- and long-term reforestation goals. The vast majority of available post-fire data represents regeneration in the first few years following a fire, raising the question of how well recovery trajectories can be predicted from early post-fire snapshots. We utilize a unique dataset from seven wildfires and 78 plots surveyed twice following stand-replacing fire in two California ecoregions, the northern Sierra Nevada and Klamath Mountains, to ask (1) how are post-fire vegetation and conifer densities changing over time and (2) how well do relatively early post-fire sampling efforts and biophysical factors (availability of seed source, shrub competition, and microclimate) explain longer-term (12–23 year) conifer recovery in California dry forests. Change in conifer seedling density between survey periods was highly variable. Overall, densities of all conifer species during the first decade after fire provided reliable estimates of longer-term conifer recovery in northern California dry forests, though in different ways for different species. Early post-fire seedling density readily explained longer-term densities for less shade-tolerant species, yellow pine (Pinus ponderosa and Pinus jeffreyi) and Douglas-fir (Pseudotsuga menziesii). In contrast, early seedling density was a poor predictor for shade-tolerant species, predominantly white fir (Abies concolor), with site conditions better explaining longer-term density. In general, the probability of a site experiencing net seedling mortality between surveys was highest in sites with high shrub cover and the probability of net recruitment increased with decreasing heat load, suggesting a continued role of microclimate and competition in forest recovery long after the initial post-fire period. Our results lend support to the use of relatively early post-fire surveys to infer longer-term forest recovery trajectories for forest management planning and can help refine reforestation prioritization tools. • Long-term post-fire conifer seedling densities can be reliably predicted from early post-fire data. • Early post-fire seedling density readily explained longer-term densities for yellow pine and Douglas-fir. • Site conditions are a strong predictor of long-term fir seedling density. • Long-term seedling mortality was more likely in sites with high shrub cover. • Long-term seedling recruitment was more likely in sites with low heat load. [ABSTRACT FROM AUTHOR]

Contaminant concentrations in filter-feeding shellfish may indicate the health of coastal waters and consumption risks. Widespread expansion of the Pacific oyster (Crassostrea gigas) and its popularity as food make it a useful sentinel. We surveyed intertidal Pacific oysters in San Diego Bay, California for contaminants during summer 2018 and winter 2019. We compared contaminants in Pacific oyster to California mussel from California's State Mussel Watch Program (1993–2003) and human consumption thresholds. Contaminants such as neonicotinoid and chlorinated pesticides, selenium, and several metals were higher in Pacific oysters in summer, while PBDEs, benzylbutyl phthalate, and plastics were higher in winter. Contaminant levels were generally lower in Pacific oyster than mussel except for copper and zinc. Bay-wide PCB concentrations in oysters exceeded thresholds but individual samples (locations) also met or surpassed chlordane, PCB and PAH thresholds. Monitoring and risk assessments that consider species' biology, season, location, effects of multiple contaminants, and human consumption patterns will contribute to more effective consumption guidelines. • Feral Pacific oysters' contamination levels vary with season and location in an urban bay. • Legacy pollutants are declining but more stormwater and runoff bring new challenges. • Site-specific pollutant hotspots add uncertainty to bay-wide risk assessments. • Monitoring and risk assessments are needed for new and emerging pollutants and species of interest. • Pacific oysters in San Diego Bay exceeded consumption thresholds for PCBs. [ABSTRACT FROM AUTHOR]