Sunday, January 15, 2012

The Blue Jay: An Avian Johnny Appleseed

A bold Blue Jay sweeps into a backyard feeding station. Some feeder-watchers bemoan the brash jays. These blue beauties are known for their brazen behavior. The little corvids do know how to make an entrance, often roaring into the yard full of bluster and bravado, scattering the lesser birds and appropriating the feeders for themselves. John James Audubon captured the devilish impudence of these saucy birds masterfully, his painting of Cyanocitta cristata quite literally depicting a jay with egg on its face.

Of course, I am describing the Blue Jay far too anthropomorphically. They do what they do, because evolution and natural selection have shaped and defined their behavior. While some people may find some of their behavioral traits less than admirable, the blue screamers are probably among the most important songbirds in the ecology of the eastern deciduous forest. Following is a brief article I penned about jays a few years back for the Ohio Division of Wildlife's On Ohio's Wild Side series:

Blue Jays: Down But Not Out

Anyone who feeds birds is familiar with the antics of blue jays, one of our most common and easily recognized songbirds. Bold and full of bluster, jays roar into the feeding station like a ton of bricks wrapped in feathers, startling more passive birds back into the shrubs.

According to Project FeederWatch, sponsored by the Cornell Lab of Ornithology, blue jays are the sixth most common species to visit Ohio feeders. Of the 373 backyard feeding stations that reported results to Cornell, jays visited over 91 percent.

So, what’s going on this winter? Many Ohioans have reported seeing few if any blue jays, especially in the extensively forested regions of southern and eastern Ohio. West Nile Virus had a detrimental impact on this species back in the early 2000s, and some fear that West Nile has reared its ugly head once again.

Fortunately, the answer to our current shortage of jays is probably much less scary than the ravages of disease. When not plundering your feeders, blue jays are highly dependent upon the nuts of oak trees – acorns. These hard, woody fruit are like vegetative M & Ms to a jay, and collectively, blue jays harvest staggering numbers of acorns in fall and winter. Fully two thirds of a jay’s diet at this time is comprised of acorns and other tree mast such as hickories and beechnuts.

A hard-working blue jay can collect several thousand nuts in one season. If the nuts are small, such as pin oak acorns or beechnuts, a skilled jay can make off with five or more at a time. They’ll quickly consume plenty of their loot, but jays are inveterate hoarders, caching far more acorns than they can immediately eat. Like a feathered pirate hiding his treasure, a jay stockpiles acorns by burying them in the ground.

While jays remember the location of many of their nut caches, they also forget about others. As a consequence, the blustery blue birds are the avian Johnny Appleseeds of the oak world, planting untold scores of oaks each year. So prolific are they in burying – and losing – acorns that some scientists think that blue jays were the primary factor in the swift northward expansion of oaks following the last glacial period.

Oaks are cyclical in their production of acorns: there are boom and bust years. In 2008, scads of acorns were produced, and jays seemed to be everywhere. Last season’s acorn crop was pretty lean, especially in southern Ohio. As a consequence, there was less food for blue jays, and thus fewer screaming bolts of blue in our woodlands. Next winter, it’ll likely be a different story.

7 comments:

Anonymous said...

I watched one consume 71 sunflower seeds. His crop was bulging. Then he stuffed another 4 or 5 in his bill before flying off. DD

Don said...

Hi Jim, Great article, Blue Jays are one of the birds that I miss living out here in the west now. We usually have a couple reports of BLJA each year here in Oregon, and this year there is a very cooperative one that showed up at a park near Corvallis and has been there going on two months. I was fortunate to see it a couple weeks ago. Maybe they're coming west :=)
Peace,
Don

Dave said...

Our Blue Jays have been busy here daily...though the Cooper's Hawk seems to have taken one, now there are three...

Andrew Lane Gibson said...

Excellent as always, Jim! In my apartment complex we have a nice mix of old and large red oaks and Norway spruces that the blue jays love to hang out in. It would not be a normal morning if I didn't hearing them 'jaying' as I walk out the door. Fantastic birds!

Jim McCormac said...

Thanks for your comments, everyone! It's hard to imagine "chasing" a Blue Jay, Don, but if a Steller's Jay showed up here we'd all be right out the door.

Nicole said...

Actually, I've noticed that I have a LOT less bird traffic in general at my feeders. I spoke with my neighbor, who's noticed the same thing. She said her brother, who lives several miles outside of Columbus (we live inside 270), has also noticed a drop in the number of birds he has. Any ideas why? We're not even getting goldfinches. Thank you.

Jim McCormac said...

Hi Nicole,

The lack of birds might be attributed to the unusual balmy weather in much of January and the lack of snow cover. Plenty of readily accessible natural food for the birds to harvest. Now that the winter has become winter - cold and snowy - your feathered visitors may soon return.