Sunday, January 21, 2018

Mealworms and Stink Bugs...tasty winter treats for Carolina Wrens!

There's no denying the Carolina Wrens in our backyard love mealworms (beetle larva), so to keep them happy I hide a stash of the larva in a tiny ceramic birdhouse in a pot on our deck. The entry hole in the birdhouse is small enough for a wren but not a starling, so the mealworms don't disappear in a hurry when the starlings (who also love them) descend in a mad feeding frenzy. Funny thing is, when the little birdhouse runs dry, the happy Carolina Wrens let me know they are unhappy by perching above the tiny house and sending me accusatory glares...

If that's not an accusatory glare I don't know what one is. 
"Where are my mealworms, woman?" seems to radiate from his adorable puffed-up self.  

Waiting...waiting...waiting for a refill...
(Is he tapping his little bird toenail in annoyance?)

...emerging from the tiny house fueled up on mealworm protein and ready for dessert...stink bugs!

Marmorated Stink Bugs 
This winter the Carolina Wrens have been especially spritely and chippy on our deck, and Rick and I have loved watching them. They've also developed a new habit...scouring the curtains fastened at the corners of our "Big Tent." It's not really a big tent, I just call it that. It's one of those canvas gazebo things we've anchored to our deck. It works really well in the summer keeping the sun off us, and, apparently, it works really well in the winter as a super secret hiding place for stink bugs trying to overwinter in peace. Unfortunately for the stink bugs, our Carolina Wrens have found them out. One day I noticed the folds in the curtains moving when suddenly a Carolina Wren popped out. He had a clearly identifiable Marmorated Stink Bug in his bill. He threw the bug down and proceeded to peck at it and then eat it. "Whoa, that's cool," went through my mind, so I watched for more. He immediately flew back up to the curtain, dove in and came back out with another Marmorated Stink Bug. Over the next few weeks, our Carolina Wrens spent a lot of time searching for and finding stink bugs in the curtains. The activity has lessened, so I think all the tasty treats have been found.

Our "Big Tent" 

The folds in the fastened curtains have become a hiding place for stink bugs.
The folds have also become a treasure trove of a winter protein source for our backyard Carolina Wrens. 

I wondered if Carolina Wrens eating overwintering stink bugs was a thing, or if ours just stumbled on the pests and were "making do" in winter, so I looked it up, and it's a thing! Carolina Wrens love stink bugs, and stink bugs like to overwinter in groups, so when they find one stink bug, they look for more in the same location. Stink bugs release an "aggregation pheromone" to attract other buddies to their super secret winter hiding places or to good feeding sources, which is why so many were hidden the folds of the curtains. Carolina wrens are cavity nesters, and they regularly search crevices and cavities for insects. Since they also take well to man-made nest boxes, it was inevitable that the wrens would search in the man-made crevices of the curtains and end up finding their winter prey.  (When insects "overwinter" they enter a hibernation-like state called "diapause.")

We never use the curtains on the Big Tent, so early this summer I thought I might take them down, but then I forgot to do it! I'm glad I forgot...and I'm also glad I didn't know the stink bugs were slowly gathering for the big winter sleep (or I would have taken them down). winter our Carolina Wrens will again  have easy hidden treats to find.

Reference links to find out more about Marmorated Stink Bugs and the aggregation pheromone:

  United States Department of Agriculture (July 16, 2014): "ASDA Researchers Identify Stink Bug Attractant"

  EntomologyToday (July 16, 2014): "Scientists Decipher Stink Bug Aggregation Pheromone"

  Rutgers New Jersey Agricultural Experiment Station: FAQ "Monitoring for the Brown Marmorated Stink Bug"

  The Journal of Natural Products, 2014, 77 (7), pp 1708-1717: "Discovery of the Aggregation Pheromone 
  of the Brown Marmorated Stink Bug (Halyomorpha halysthrough the Creation of Stereoisomeric 
  Libraries of 1-Bisabolen-3-ols"

Monday, January 15, 2018

Red in the Hornbeam

It doesn't matter how cold or gray it gets outside, Northern Cardinals burn bright...

A Northern Cardinal in the American Hornbeam in our backyard. 

Thursday, January 4, 2018

Fast food isn't good for you anyway, Mr. Red-shouldered Hawk!

Our resident Red-shouldered Hawk decided he was tired of sitting in the tree waiting for an unsuspecting meal to fly by, so he went directly to the source for a little fast-food takeout. Apparently word got out that the local "McTitmouse" was under surveillance, so our backyard birds went somewhere else for dinner...

A Red-shouldered Hawk perches on our platform feeder. The Dark-eyed Juncos, White-throated Sparrows, White-crowned Sparrows, Chickadees, Titmice, Carolina Wrens, woodpeckers, and Northern Cardinals that usually dine there were not amused. They fled for safer ground.

...the shutter clicked in time to catch his nictitating membrane covering his eye.  
If you want to see a nictitating membrane in action, click here to go to a video that shows it covering the eye in slow motion. It's cool to watch because the membrane closes horizontally from the medial corner to the lateral corner, not vertically like our eye lid.

Uh ohhh....he hears my camera click, and now he's not amused.

Our Red-shouldered Hawk sat on the feeder for a while, to no avail. He eventually flew off to find his dinner elsewhere.