Laura Erickson's For the Birds

Monday, January 19, 2015

Western Scrub-Jay Funerals

Western Scrub-Jay
Western Scrub-Jay
Back in 2012, a paper in the journal Animal Behavior presented a study about Western Scrub-Jays titled “Western scrub-jay funerals: cacophonous aggregations in response to dead conspecifics.” Researchers placed several objects, including pieces of wood, stuffed scrub jays, stuffed Great Horned Owls, and dead scrub jay carcasses, into people’s backyards to observe how the neighborhood scrub jays responded. Jays are naturally curious, and they discovered and inspected all the objects, though spent very little time checking out the wood. 

Dead scrub jays that had been stuffed and mounted in life-like poses elicited aggression. I’ve often noticed that sociable birds seem more distressed and aggressive toward a bird of their own species when that bird looks or acts different from the others. When I rehabbed, I could never let an injured crow out in my yard, because neighborhood crows would attack it. Intriguingly, many published observations as well as my own find that when a crow is injured or has a physical deformity, its family and neighborhood flock mates do not attack it, but often actually provide help, bringing it food and protecting it from nearby predators. But the combination of being a stranger and acting odd elicits aggression in crows, much as many of our own species have trouble dealing with people who look or act different from them. Something that looks like a perfectly normal jay but doesn’t move or react to others would seem pretty odd to jays who have never experienced such a thing before.

Great Horned Owl
Great Horned Owl
A stuffed and mounted Great Horned Owl elicited “hundreds of long-range communication vocalizations.” Squawking to beat the band calls in squads of other scrub jays, as the birds alert one another to the danger and work together to drive the predator away. Intriguingly, the researchers found that a prostrate dead jay also got a similar response, both in the high number of calls and in drawing in other scrub jays from afar. I noticed something similar with Blue Jays, back in the days when I was an occasional counter at Hawk Ridge. If a hawk nailed a Blue Jay out of a flock of migrants, the whole group remained in the area, often for 45 minutes or longer, yelling their heads off in what I called an Irish wake.

Both the mounted owl and the dead scrub jay caused the other scrub jays to decrease their foraging for food in the area for over 24 hours. The authors concluded in their abstract, “Our results show that without witnessing the struggle and manner of death, the sight of a dead conspecific is used as public information and that this information is actively shared with conspecifics and used to reduce exposure to risk.”

For some reason, a story about that research paper went around on Facebook last week as if it were new information, and several birders quickly started criticizing the authors’ use of the word “funeral.” That and my own use of “Irish wake” naturally smack of anthropomorphism. 

We humans can’t help but compare animal behaviors to our own. It is completely unscientific to draw a conclusion that animals grieve the loss of individuals or recognize death in the same way we humans do, but it’s equally unscientific to state that they don’t. In the study, those Western Scrub-Jays were hardly grieving the loss of one of their own—the authors didn’t kill a local jay for their dead specimen, so of course the jay wasn’t recognized as a particular individual, and the jays’ reactions almost certainly couldn't be called grief. But the ways we humans announce and gather after the deaths of our own conspecifics suggest that our funerals may serve the same purpose as the gatherings of those scrub-jays. We can’t yell as loud as they, but we ring the alarm far and wide in the obituary pages of our newspapers and on the news. Our own funerals involve family and close friends grieving for the loss of someone they love, but also include the wider community, many who are not grieving at all. If you listen in on conversations at any wake or funeral, you’ll hear people, including genuinely grieving loved ones, talking about the cause of death in ways that suggest we’re all using that information in hopes of forestalling our own deaths, just as the scrub-jays of the study apparently did. Some people pooh-pooh the idea that animals are capable of understanding death or envisioning their own. But we have plenty of evidence that a lot of humans, and not just reckless teenagers, can’t envision our own mortality or wrap our own heads around the concept of death, either.

Lots of data affirm that some species of birds and mammals suffer physiological stress after the death of a mate or young similar to the physiological stress of grieving humans. It’s fun to think we’re superior to animals and capable of deeper love than they, but considering the high murder and divorce rates between family members in our own species, that superiority is pretty questionable. Every species reacts to different things in different ways—including us—but we share a lot of common ground. Dismissing the term “funeral” for the scrub jays in this study seems to deny that truth. If we ever came upon intelligent life forms in outer space, there is no way we could hope to communicate with them until we figure out how to better understand and communicate with the intelligent life forms right here on earth.

Western Scrub-Jay

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