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Capes and cape-associated shoals represent sites of convergent sediment transport, and can provide points of relative coastal stability, navigation hazards, and offshore sand resources. Shoal evolution is commonly impacted by the regional wave climate. In the Arctic, changing sea-ice conditions are leading to (a) longer open-water seasons when waves can contribute to sediment transport, and (b) an intensified wave climate (related to duration of open water and expanding fetch). At Blossom Shoals offshore of Icy Cape in the Chukchi Sea, these changes have led to a five-fold increase in the amount of time that sand is mobile at a 31-m water depth site between the period 1953-1989 and the period 1990-2022. Wave conditions conducive to sand transport are still limited to less than 2% of the year, however--and thus it is not surprising that the overall morphology of the shoals has changed little in 70 years, despite evidence of active sand transport in the form of 1-m-scale sand waves on the flanks of the shoals which heal ice keel scours formed during the winter. Suspended-sediment transport is relatively weak due to limited sources of mud nearby, but can be observed in a net northeastward direction during the winter (driven by the Alaska Coastal Current under the ice) and in a southwestward direction during open-water wind events. Longer open-water seasons mean that annual net northeastward transport of fine sediment may weaken, with implications for the residence time of fine-grained sediments and particle-associated nutrients in the Chukchi Sea. Plain Language Summary Offshore of coastal headlands, large sand ridges (on the scale of 1-10 m high) commonly occur. These features can change shape and migrate over decades to centuries, especially as conditions change in the ocean--for example, when wave energy increases and/or sea level rises. Here we explore the shape and sediments of Blossom Shoals offshore of Icy Cape in northwestern Alaska. These ridges are dominated by sands, though muds travel through the system during storms (and are likely sourced from the adjacent lagoons) and during the winter when sea ice covers the ocean. These shoals appear to have changed little in shape over the past 70 years, though stronger waves in the present climate mean that sands in the shoals are mobile for more time each year, which means the shoals may change shape and/or location in the future. Muddy sediments tend to flow northeastward (on average) over the course of a year, but longer open-water seasons mean that these sediments may spend a greater portion of each year traveling southwestward--representing a possible change in the typical pathway of sediments and related nutrients (like carbon). [ABSTRACT FROM AUTHOR]