They probably feed at night in estuarine habitats. In the winter they make periodic short flights from the intertidal mudflats to their high tide roosts. The fall migrants begin arriving on the central coast of California in late June. By approximately mid-April most of the curlews have left for their breeding grounds. The long-billed curlew uses its distinct long bill to probe deep into the substrate or to grab prey from mud surfaces.
Prey consists of mud crabs, ghost shrimp, and mud shrimp.
They have also been reported to forage on insect pupae, gem clams and small estuarine fish. The breeding range has receded considerably in the last 80 years. Long-billed curlews were not observed or reported with the study reaches as defined. They probably do, however, use the open grasslands areas adjacent to the river. Only those projects that would affect the grasslands could have negative impacts to this species.