Friday, August 31, 2012

Jays in My Backyard

Western Scrub-Jay (©Ken R. Schneider)
Earlier this summer, I had the pleasure of watching two fledgling Western Scrub-Jays learn from consequences.  They were perched on my brush pile underneath my redwood when I spotted them, and clearly had left the nest not long before.  They were waiting impatiently for their parents, who stopped by regularly with food that got eagerly grabbed.  Meanwhile, they explored their surroundings.  One found a small yellow leaf, trapped it under one foot and pecked at it, as if checking whether it was good to eat (no).  It was discarded.  The other youngster poked around a bit too, also without success.  Still, it was a start on the path to independence.

One week later, I watched what was probably one of these youngsters in my yard again, this time foraging more actively, picking up dead grass stalks systematically.  Once again, its efforts did not appear to be crowned with success, but it was trying.

The adults are omnivorous, kind of like feathered bears:  They’ll go after anything that’s edible.  And they readily learn their way around minor obstacles.  Someone in my neighborhood feeds peanuts in the shell, and the birds come to particular flat fencepost stumps in my backyard to hold them down and peck them open with their all-purpose beaks.  I'm sure the youngsters will be up to that--someday.

Update:   I happened to catch a cool scrub jay post on animal expert Sophia Yin's blog (link here).  As she reports, two scientists published a 1999 Nature article on how jays learn from consequences when they store food like nuts in hidden "caches."  The nuts last a long time, but cached foods like waxworms don't.  It turns out that "the birds had to learn that food such as waxworms degrade after long intervals. A separate set of scrub jays whose rotten waxworms were secretly replaced with fresh ones after long intervals, never learned that waxworms go bad."  And they behaved accordingly, very differently from the jays that had learned otherwise.  The flexibility provided by learning--even if it's researcher-assisted and "unnatural"--helps the birds survive.


  1. The reinforcement value of non-consumable stimuli is underrated, I believe. I have young Scrub-Jays and Mocking Birds growing up in my front yard. I often work out in my garage, which faces the front yard, with the garage door partly down. To raise the reinforcement value of the activity for me, I play Trance/Rave music while I exercise. The interesting thing is that the young birds hang around the garage door singing vigorously in reply to the music (they are probably too young to know that it is merely human nonsense noise). A couple of times a jay actually flew into the garage to check out what bird was singing those strange songs.

  2. Thanks, Stephen, what fun! The mockingbirds might actually be picking up new ideas for their repertoires. They've been known to imitate unnatural sounds like car alarms, after all . . .