Ingested plastics reduce recruitment and survival of an Australian seabird.

Plastics research lags 30 y behind many other environmental crises, with population-level impacts alluded to but not yet demonstrated for any wild species. Addressing this "Grand Challenge" requires robust data that span many years of variable exposure. Here, we use 15 y of mark-recapture data to estimate plastics' impact on the demography of Sable Shearwaters (Ardenna carneipes). We found that the ingestion of >1 g of plastic is common and associated with at least an 11% reduction in the probability of birds surviving to return and breed at their natal island, with birds that ingested >5 g of plastic almost never seen again. In a time of unprecedented planetary change and biodiversity collapse, these results provide much-needed insight into plastics' role in potentially driving species decline.