Duck swallowed alien?

This delightful image of an alien was found in an X-ray image of an ill duck at the International Bird Rescue Research Center in Coredlia, California. From the San Francisco Chronicle (photo by Carloa Avila Gonzalez):

The drake in question arrived at the center Sunday with a broken wing. Workers do not know how the mallard was injured, but it was clearly weak and emaciated. In an effort to pinpoint the trouble, Maria Travers, the assistant rehabilitation manager, took a radiograph image of the bird. She was stunned by what she saw.

"Look at this," she shouted. "It's an alien head!"

Holcomb admitted the strange image could have been an odd arrangement of grain in the stomach...

Link (Thanks to the many readers who submitted this one.)