An innovative cobble tracer study is advancing our understanding of coarse beach sediment transport while engaging students in hands-on learning along the Lake Ontario shoreline. The southeastern shoreline of Lake Ontario is dynamic and continually shaped by wave conditions, precipitation patterns, fluctuations in lake levels, and interactions with shoreline infrastructure. These factors influence the transport of sediment that sustains Lake Ontario’s beaches and barrier bars; however, these processes remain poorly understood. To address this data need, the Lake Ontario Sediment Tracer Study was launched to better understand sediment transport along McIntyre’s and Whistlewood Bluffs. Beaches at these sites consist of sand, pebbles, and cobbles. The study deployed two types of tracers: painted pebbles (0.5–1.5 inches) and pebbles/small cobbles (1.5–5 inches) equipped with embedded passive integrated transponders (“smart rocks”). These tracers were used to track coarse sediment transport rates, directions, and potential movement barriers from fall 2025 through 2026. This presentation will share findings from the tracer study and highlight a collaborative partnership among state agencies, private consultants, New York Sea Grant, and the Sterling Nature Center. Together, these partners developed the three-part “Track-the-Tracers” Shoreline Adventure, which engaged rural home-school students in designing, deploying, and tracking their own cobble tracers along the shoreline.
