We present a record of sea ice and climate inferred from novel snow petrel stomach oil deposits from East Antarctica. Snow petrels feed in the sea ice on a mixture of marine organisms and regurgitate these oils close to their nesting sites in nunatak mountains. We use makers of past diet and productivity from within a deposit to show how sea ice and climate has varied over part of the Holocene. Three periods are identified ranging from low to intermediate and increased sea ice cover.