Avian influenza strain H5N1 has been identified in Caspian terns (Hydroprone caspia) that nest on Rat Island near Port Townsend WA.  Rat Island is part of the Fort Flagler State Park at the entry to Admiralty Inlet leading to Puget Sound.  Caspian terns interact with other migratory birds and domestic free-living shore birds on the Skagit Flats and adjacent wetlands.

The presence of migratory terns shedding H5N1 is of concern to poultry in northwest Washington State and the relatively dense population of commercial poultry in the Fraser Valley of British Columbia, north of the U. S. border.