Globally, little is known about the dispersal of microplastics (MP) and anthropogenic particles (AP) via atmospheric deposition (AD) into water bodies. Correlating AD to the large number of MP in estuaries is challenging but an important first step toward reducing this form of pollution. A previously published model of the surface waters of the Indian River Lagoon (IRL, east central coast of Florida, USA) estimated it contained 1.4 trillion microplastics. To determine if AD could produce this much plastic deposition, we deployed passive AD collectors throughout a 145 km² area at three site types with assistance from citizen scientists. We predicted that the rate of deposition of MP and AP would be greatest in residential areas, intermediate within a national park, and lowest on intertidal oyster reefs. Moreover, we predicted Florida’s wet season and individual rain events would increase deposition based on the published literature. Over 14 months, deposition averaged 1224 MP/m²/d; extrapolated, this yields 1.1 trillion MP for the lagoon-wide total deposition estimate (95% CI: 0.86–1.39 trillion MP). This value suggests that AD may represent an important pathway for MP to enter this estuary. More MP were deposited during rain events and in the wet season, with no differences among sites. Overall, our results provide important data for understanding AD of MP and AP in estuaries.

Oyster reef restoration has become increasingly crucial due to global population declines. Intertidal oyster reefs provide essential foraging and loafing (resting) grounds to estuarine fauna. To reduce plastic pollution from traditional materials, biodegradable restoration materials have been introduced and are shown to support oyster recruitment. However, faunal responses to these materials are unknown. This project evaluated the effects of biodegradable oyster reef restoration materials on vertebrate abundance, diversity, and behavior. Camera traps were deployed on Eastern oyster ( Crassostrea virginica ) reefs in summer 2021, winter 2022, and summer 2022 for a total of 117 days in Mosquito Lagoon, Florida, United States. Treatments included Biodegradable EcoSystem Engineering Elements (BESE) mats with attached recycled oyster shells, cement‐jute tiles, and cement‐jute rings. Unrestored, live oyster reefs were used as positive controls, and unrestored, dead reefs (piles of disarticulated shell) as negative controls, with three replicates of each treatment. A total of 10,872 vertebrates (birds and small mammals) comprising 43 species were observed from 68,890 video clips. Bird diversity, community assemblages, and mammal abundance were similar between treatments. Bird abundance on all restoration treatments was comparable to live reefs, while it was significantly higher on dead reefs (generalized linear mixed model: p < 0.001). Oyster reefs restored with BESE mats and cement‐jute tiles supported the same level of foraging as live reefs, whereas cement‐jute ring reefs and dead reefs exhibited higher loafing activity. These findings highlight the importance of selecting appropriate restoration materials to ensure the success of oyster reef restoration efforts.