The state Department of Fish and Wildlife is again operating a hotline for people to report dead, sick or injured swans in three northwest Washington counties. The hotline is part of the department’s ongoing effort to assess the impact of lead poisoning on trumpeter swans.

People can call 360-466-4345, ext. 266, to report dead, sick or injured swans seen in Whatcom, Skagit and Snohomish counties. Callers are asked to leave a message that includes their name and phone number, and the location and condition of the swans. The hotline will be available 24 hours a day through the end of March.

Some trumpeter swans in the three counties, as well as in southwestern British Columbia, die each winter from lead poisoning after ingesting lead shot in areas where they feed.

Lead shot has been banned for waterfowl hunting in Washington and British Columbia for more than a decade. But swans can still pick up and ingest lead shot while foraging in shallow underwater areas in fields and roosts where lead shot is still present.

People who observe dead, sick or injured swans are advised not to handle or collect the birds, said Chris Danilson, wildlife biologist for Skagit and Whatcom counties. Instead, people should call the hotline, he said. The state agency and Puget Sound Energy employees, as well as volunteers from the Washington Waterfowl Association and the Trumpeter Swan Society, will pick up the birds.

The department and other agencies and organizations have been working since 2001 to locate sources of toxic lead.

Since 2006, biologists have used various hazing techniques to discourage swans from using Judson Lake, a significant source of lead poisoning on the U.S.-Canada border in Whatcom County. Danilson said that as a result of this effort, the number of lead-related swan mortalities in northern Puget Sound has declined significantly.