This summer one of the largest birds in North America suddenly showed up in Washington state's Puget Sound.

Squadrons of white pelicans have set area birders atwitter. They’re trying to figure out where the birds came from and what their arrival means.

While this rare sighting has been fun for bird watchers, Katie Campbell from Here & Now contributor Earthfix reports on why it may not be a good thing for the pelicans.

Katie Campbell, reporter for Earthfix. She tweets @KatieCampbell.