5-second rule

As reported by Irby Lovette for Living Bird, research by Tomohiro Kuwae et al. provides evidence that Western Sandpipers (Calidris mauri) take a substantial portion of their diet from the biofilm that forms on tidal mudflats. Studying birds during spring migration in the Fraser River estuary in British Columbia, the authors back up their findings with high-speed video and analysis of stomach contents. In addition to the known diet of these beach foragers—macroinvertebrates such as polychaetes, molluscs, crustaceans, and insects—the gooey millimeter-thin layer of “microbes, organic detritus, and sediment in a mucilaginous matrix of extracellular polymeric substances together with non-carbohydate components secreted by microphytobenthos and benthic bacteria” provides up to 50% of the bird’s energy requirements, according to Kuwae and fellow scientists. They also cite previous research that the bill and tongue structure of the Dunlin (Calidris alpina) would also be suitable for biofilm grazing.