Science Daily:

Working in the backyards of homes in Davis, Calif., [Teresa Iglesias, the UC Davis graduate student] set up feeding tables to encourage visits from the jays. Then she videotaped their behavior when she placed a dead jay on the ground. She compared these reactions with the birds' behavior when confronted with a dead jay that had been stuffed and mounted on a perch, a stuffed horned owl, and wood painted to represent jay feathers.
On encountering a dead jay, prostrate on the ground, jays flew into a tree and began a series of loud, screeching calls that attracted other jays. The summoned birds perched on trees and fences around the body and joined in the calling. These cacophonous gatherings could last from a few seconds to as long as 30 minutes.
Jays formed similar cacophonous gatherings in response to a mounted owl, but ignored painted wood. When confronted with a mounted jay, the birds swooped in on it as if it were an intruder.
This bird is no ordinary bird. It's a member of the corvid family (crows, ravens, rooks). The more one learns about corvids, the more one starts to think about intelligence as not so wonderful or specific to great apes but as a niche that's available to other evolutionary lines or paths.