PROVIDENCE — A bird flu virus strain has been found in four mute swans collected from the Seekonk River — near the Swan Point Cemetery — as part of routine surveillance by the state Department of Environmental Management.

While the DEM says the strain is not harmful to humans, the agency is suggesting that all poultry owners have their flocks tested.

Tests by the U.S. Department of Agriculture detected that the swans, part of a sample of 11 birds, were infected with the H7N3 strain of avian influenza virus.

But the DEM emphasized in a news release yesterday that it is not the same strain that has infected people in Asia and Europe since 2003, and there is no known significant health risk to people who are exposed to this strain of the virus.

However, the virus can be transmitted to other birds and poses a significant risk to other wild birds and domestic poultry flocks. So DEM’s Division of Agriculture will increase surveillance of domestic poultry flocks within a 6.2 mile radius of where the infected swans were found.

The Massachusetts Department of Agriculture will do the same in the Bay State.

Rhode Island DEM’s Division of Fish and Wildlife will also increase surveillance of wild waterfowl, including swans, ducks, and geese.

As a precaution, the DEM said, all poultry owners, to protect their flocks, should enact standard biosecurity and sanitation practices. Poultry owners should prevent their flocks from contact with wild birds.

The public is also asked to avoid feeding waterfowl and to report sightings of dead or sick birds to the DEM’s Division of Fish and Wildlife at (401) 789-7481.

Additional information on avian influenza and steps poultry owners should take to protect their flocks can be found at www.dem.ri.gov/topics/avianflu.htm.

mmckinne@projo.com