Wrens were always the little birds I'd read about in novels, praised for their beautiful songs and cheery natures. I knew nothing else about them, other than that some parents name their daughters Wren (personally, I'd prefer being named Peregrine or Kestrel). The June 2009 newsletter from Wild Birds Unlimited, however, noted that June was wren-nesting month. Since WBU was correct about June also being the month groundhog babies emerged (an event that forced us to rename Walter, our resident groundhog, Waltina), I figured that this was my chance to see and hear what wrens were all about. I bought a wren house, a little diamond-shaped wooden affair with no way to open except to actually unscrew the entire thing -- not very practical for checking nesting and clutching habits. At the least, I thought, it could serve as yard art, a cute Victorian-style contraption that blended well with the landscaping of my front garden. The tree in which it hangs stands right outside the window of my temporary office. My thoughts were to be able to observe a little wren singing and raising a family just a few feet away.
The wrens had other ideas.
For about two weeks, the little white wren house just hung there, doing nothing other than adding focal interest to my yard. Concerned that perhaps the little birds weren't fond of the corrugated copper roof on the house, I bought a plain cedar wren house and hung it opposite the first one, on the other side of the tree but still well within my view.
A few days later, I heard it. Wren song is very hard to describe. It's a combination of trilling and high-pitched laughter that lasts for a long time, at least in bird terms. It's not a quick caw or coo, but an extended enunciation that repeats after a few moments. Accustomed to short bird calls, I was enchanted by this little songster and actually managed to capture him mid-song with my camera. I'd read that wrens sing from dawn to dusk, and I looked forward to having the little wren perched on his house just outside my office, warbling away all day.
The next morning, I awakened to the sound of wren song as the little bird trilled his heart out from the higher branches of my tree.
The following morning, I began to wish the wren would go perch on a different tree. The little guy just sang and sang and sang, non-stop, from about 5:30 AM on. Having stayed up late unpacking boxes, I just wanted to lay my heavy head back down and sleep a little more. The wren didn't care, however, and eventually I gave up and got an early start on my day.
That evening, one of the crazy storms that sweeps through this part of Michigan hit. These can be vicious -- an earlier storm tore our flag and flagpole holder right off the front of our house. This time, the wind shrieked through the attic rafters and caused the house to creak throughout the night. J woke up early the next day -- I never did ask him if this was due to the wren alarm clock -- and walked the property, looking for damage. The only casualty was the cedar wren house, which had been flung about 5 feet from where I'd hung it. Fortunately, it was intact, but I could only think with horror about what might have happened had there been a nesting female inside. That afternoon, I purchased an extra-strong cable with s-hook and lashed the little house to the tree.
When I checked the house the next morning to see if it held, I noticed twigs sticking out of the entrance hole. I was thrilled -- my little singer had chosen to build a nest in one of my houses! For a few days, I kept checking the Victorian wren house, hoping that perhaps he'd move to the ritzier house, but no go. Another let down came when I checked my bird-nesting book. Apparently, male wrens are prodigious builders -- they will stuff twigs into any available cavity in their territory, building "dummy nests" that may or may not be used. The choice came down to the female, whom the male wren would take on a tour of his assorted estates. The female wren would then choose one of the nests the male had built, complete it with more sticks and twigs, gum the whole works together with spiderwebs and sticky white caterpillar coccoon threads, then make a soft cup-shaped depression in the back lined with soft grasses and feathers. In this, she'd lay her eggs.
The female wren apparently did not like the cedar wren house. At least, that's what I think. I tried peering into that small circular opening with a flashlight to see if an active nest was inside, but I couldn't see past the front twigs... which I believe is the purpose of those twigs any way, a sort of protective barricade behind which the birds are free to clutch and brood. I had some hope still, since the front twigs have the gummy white threads on them, but without being able to open the box and monitor what is inside, I had no way of verifying whether the nest was active or not. And I really didn't want to undo all the lashing and unscrew the house just to check. Another bird book suggests removing dummy nests after three weeks, to allow other birds to use the cavity. I'm on week two right now, still maintaining a little hope that the nest is an active one, even though the wren no longer sings from this tree.
Another wren -- we have several now, all trilling from different parts of our property -- also shunned the wren houses I set up, choosing instead the newest bluebird nesting box N and I set up in the backyard. This box is the farthest point in our bluebird trail, and the wren must have been itching to nest because the day after we put the nesting box in, the wren had built her nest. At that point, I was so used to opening up the boxes and finding either nothing or messy house sparrow nests inside that I momentarily froze when I opened this box and found a tall pile of gummy twigs inside.
I also panicked. There was a video clip on Sialis showing a house wren tossing bluebird nestlings out of their nest so that she could occupy the space. I'd read about bluebird eggs being pecked open by long, sharp wren beaks. I did not want this little wren to wreak havoc on my skittish bluebirds. Luckily, Lynn at the Michigan Bluebird Society allayed my fears. She shared her experience with house wrens: if you keep removing their nesting materials, they become aggressive and retaliate by moving to another available cavity and making it their own. In the case of a bluebird trail, this usually meant displacing an established bluebird couple or going around pecking eggs and baby birds -- obstacles to getting a quiet cavity in which to nest. Once Lynn chose to leave the wren alone, it built its nest and minded its own business, not bothering the nearby bluebirds at all. Her wren became a good neighbor to her blues. As I pondered this, Lynn reminded me that wrens are protected birds -- once the nest was active, it could not be touched.
I took that to mean that while it was inactive, I could empty the nesting box out. I headed out to the bluebird trail, angled mirror in hand, to see if I could still salvage this box. When I opened the door, however, the change was immediately apparent: twigs were now packed in all the way to the ceiling and, when I carefully peeked beyond the barricade, I saw a nesting cup in the back. I closed the door in gracious defeat.
Since that day, I've monitored the wren's box along with my other trail boxes and excitedly reported to my family the appearance of one, then two, then three eggs. A few days ago, I felt another kind of wren-related anxiety: the number of eggs remained stuck at three. I knew from my research that a wren clutch averaged 7 eggs, one per day. What had happened? Had I checked the nest too often, scaring the wren away? Had Sean, my aggressive male bluebird, chased the wren away from a nesting box he viewed as his own? What could I do to save the abandoned eggs?
Fortunately, as I rinsed dishes yesterday afternoon, I saw two little shapes flitting around the far box. Grabbing the binoculars, I zoomed in and, with relief, saw two wrens, one going into the box, the other perching on top. Phew! I'll give them a few days to themselves before I check on their eggs again, and then I'll leave them be until it's close to hatching time, just to make sure no one has snacked on them
As for my cedar wren house, my curiosity will probably get the better of me and I'll probably take it down soon to check if it's a dummy nest or not. That'll mean scaling the tree to unlash the cable and hooks, ugh, to I'll have to wait for a warm day and, preferably, one without wind.
And, of course, I have to wait for a time when my hummingbirds aren't flitting around the tree, which seems to be their pasttime of choice. But the hummers are yet another tale...
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