BBC Nature says it’s less likely the assembly resembles any form of acknowledgement of the passing of a dead bird and more likely it’s a symbolic behavior designed to warn other birds there may be a threat nearby.
Scientists have tested out the ritual of the jays by placing various objects in areas where jays are known to congregate, including the backyards of many American homes. The objects ranged from wood, models of predators, and dead jays. Most of the objects were ignored, except for the dead jays, where the signalling behavior was initiated. The ritual then proceeded to last for up to one day.
The western scrub jay (Aphelocoma californica) is a species of scrub jay native to western North America. The bird is approximately 11.5 inches in length (including its tail), with a 15-inch wingspan. The jay has a blue head, wings, and tail, a gray-brown back, and grayish underparts. The throat is whitish with a blue necklace.
A study and analysis of the jay ritual has been published in the journal Animal Behavior, in a paper titled ‘Western scrub-jay funerals: cacophonous aggregations in response to dead conspecifics’.
