Fig. 1: Antarctic scallops inhabit anchor-ice zones in Antarctica yet appear to remain ice-free.

a Typical vertical profile of seawater conditions in austral spring in McMurdo Sound, Antarctica (14th Nov, 2012) showing seawater supercooling. Seawater supercooling drives anchor-ice growth, the prevalence, and thickness of which typically increases towards shallower depths. b Schematic representation of the anchor-ice zones in Explorer’s Cove, McMurdo Sound, Antarctica, informally defined herein using the definitions established by Dayton et al.²⁶. c–e In Explorer’s Cove, Antarctic scallops occur in all zones, including the heavily anchor ice impacted shallowest areas (Zone 1, c) where they are found atop the growing anchor-ice blanket. Despite the abundant ice accretion on rocks and sediment in Zones 1 and 2, cryofouling of the exterior of the scallops’ mineral shells was never observed.