JACKSON HOLE, Wyo. (AP) — Hundreds of trumpeter swans have flown on their annual migration route to winter in the marshes of the National Elk Refuge in western Wyoming.

Wyoming Game and Fish Department biologists have counted a record-high 437 swans at the refuge near Jackson Hole during the survey earlier this month.

Most of the swans live in the Canadian taiga during the summer and typically arrive in Wyoming in late October. Wildlife biologist Susan Patla says the warmer weather has caused many swans to move around to sites that are usually frozen this time of year instead of settling in for the winter.

Patla says about a thousand trumpeters typically spend their winters in Wyoming, and their migration ranges are expanding farther south.

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