Antibodies to Influenza A Viruses in Gulls at Delaware Bay, USA.

Gulls are the known reservoir for H13 and H16 influenza A viruses (IAV) but also host a diversity of other IAV subtypes. Gulls also share habitats with both ducks and shorebirds, increasing the potential for cross-species IAV transmission. We serologically tested laughing gulls (Leucophaeus atricilla) collected at Delaware Bay during May when they were in direct contact with IAV-infected shorebirds; both species feed on horseshoe crab (Limulus polyphemus) eggs on beaches during this month.