JOHN PEPIN

“Bird on the horizon, sitting on a fence. He’s singing his song for me at his own expense,” – Bob Dylan

A year or so ago, I was walking down our driveway to the mailbox when I heard a male house wren singing from a thick grove of trees across the county road.

It’s one of those bubbly and ebullient songs often typically associated with wrens — a song you hear all over the place once you recognize it.

I hear it often when I get out of my car in the parking lot at work. I even heard it during one of the scenes in “Oppenheimer.”

The loud and cheerful song is unexpected from this little, brown, fidgety 5-inch-long bird with a cocked tail. The Ojibwe named the house wren is O-dun-na’-mis-sug-ud-da-we’-shi, which translates to a big noise for its size.

When I heard it on that summery day, it made me wonder why we hadn’t attracted any nesting house wrens to our yard. After all, we have a bluebird/tree swallow box on one of the tree trunks along the driveway.

I theorized that the opening to the box was too big for wrens, though I found out later that this is not the case. Either way, I decided to get a wren box put up last fall with anticipation of potential wren nesting this year.

When springtime came, I discovered the bluebird box was occupied by a flying squirrel that obliged me by sticking its head out of the opening with a wink and a nod, after I gently tapped a couple times on the side of the box.

A few days later, it was quite satisfying to hear a male house wren singing near the new wren box. It was even more exciting to see two wrens perched on top of the box, with one going inside and then quickly popping back out again.

This was no doubt an inspection tour.

The male wren places coarse sticks in the bottom of potential nesting sites and then brings a female attracted to his song around to these sites for her approval.

Sometimes, the female rejects the house. Other times, she may accept the house and the location but reject the nest the male had started. She will then take all the sticks out of the house to start over.

Once nest-building has begun in earnest, the male packs dried sticks into the bottom of a nest box, filling it almost all the way to the top. The female will then bring soft grasses and other lining to finish the nest.

House wrens will nest in all kinds of locations. Some of the places I’ve read about include a rusty tin can on a junk pile, in the pocket of a scarecrow or in a garden watering can hanging on a fence.

House wrens also nest in nests of other birds and even old wasp nests.

Whatever the site, the wrens fill the space with nesting material.

One of the weirdest and coolest things I read was that a man who was ill and laid up in his cabin watched a wren pair’s nest-building, egg-laying and chick-fledging processes close at hand.

The birds had found their way into the man’s cabin through holes in the cabin wall to nest in a pigeon-hole compartment in his desk.

In our case, the wrens soon began building a nest inside the new wren box a few days after I saw the pair checking out the box.

Meanwhile, a few days later, I was surprised to see a male house wren singing from the top of our purple martin house in the backyard. We watched him enter several of the nest holes in the apartment-style bird house.

After a few days, we lowered the nest box down with a crank and checked inside. There were sticks placed in the nest box apartments on the east, west and south sides of the nest box. Nothing on the north.

The bottom apartment on the south side showed the greatest nest building activity, with a good number of sticks packed inside.

A characteristic of wrens is to build extra or “dummy” nests. So, we wondered whether this nest in the martin house also was constructed by the pair in the wren box or were we seeing the nesting activity of two separate pairs of wrens.

We were a little concerned about the idea of two pairs of wrens nesting so close to each other. Once their nesting territory is established, they may fight off competitors by piercing their eggs, dragging out the young or even killing other house wrens.

More birdwatching provided the details, as it usually does.

The birds in the martin house appeared to be a week or so behind those nesting in the wren box. So, as we observed increased and repeated trips with food to the wren box, the wrens in the martin house remained more passively active.

This appeared to be two separate pairs of birds.

House wrens become easily fussy about human presence anywhere near a nesting location, delivering a loud, scolding and buzzing call.

They would do this repeatedly from the low shrubbery if I merely appeared in the backyard anywhere or if I walked down the driveway.

This is more show than anything else, as wrens are quite comfortable living around humans, and vice-versa.

After sitting quietly to take pictures from the driveway one day, the wrens became comfortable with my presence after a few minutes and resumed their comings and goings to and from the nest box.

Wrens typically lay a half-dozen eggs in a clutch but have laid twice as many in some instances.

According to the sick guy in the cabin from the late 1800s, nest building began on April 15, with the nest completed and the first egg laid April 27. The last egg was laid May 3, with incubation begun the following day. Hatching was complete by May 18 and the young began to fly May 27, leaving the nest for good on June 1.

After nesting in the springtime, house wrens typically repeat the process of finding a mate, looking for a suitable nesting location, nest-building and brood-raising. Sometimes, the females will mate with the same male, sometimes not.

In cases where they select the same nest for their second brood of the season, house wrens often remove all the nesting material – stick-by-stick and start over.

A few days after I took the pictures, I woke up to the sound of chicks peeping for food. It was so loud I could hear it inside our house with the windows closed.

I watched the wrens now increase their activity to bring insect food to the nest. I snapped a few pictures of the young with their heads sticking out of the doorway, begging for food with their mouths wide open.

I was concerned that the loud noise coming from the box might be a location giveaway to predators like cats, snakes and red squirrels that would love a wren chick meal.

Almost as quickly as it started, the peeping stopped.

The next day, the box was quiet – dead quiet.

After a couple more days of silence, I decided to open the nest box and found four chicks dead in the nest, another down in the bottom of the sticks and whitewash splattered beneath the nest hole and partially inside the box.

It appeared that something had killed the adults and they were unable to return to the box. I later read that sometimes adults abandon the nest box with chicks inside.

Chicks are also killed, or the parents driven away, by parasites or spiders that overrun a nest box. The weather was hot that day, but young wrens are not supposed to be affected by heat until the temperature rises above 93 degrees.

As I said previously, wrens can also be killed by other house wrens.

We cleaned out the nest and the dead chicks and opened the box to let it air out.

It was a gravely disappointing affair.

Thank goodness the second pair of wrens continues to occupy the martin house and is now making repeated trips to peeping chicks in their skyline apartment.

They are still making buzzing sounds, but the song singing has diminished for now, although one of the house wren traits is to continue singing after nesting has been completed.

As the nights get colder and daylight diminishes, the wrens migrate south to warmer climes where they retreat to forests. A couple weeks before they fly back north in the spring, they begin to sing strange songs, atypical of a house wren song.

If I was that tiny and had to physically fly hundreds and hundreds of miles north to nest every year and then fly back, I think I’d be signing a strange song too, and like the house wrens, it wouldn’t necessarily be a happy song.

EDITOR’S NOTE: Outdoors North is a weekly column produced by the Michigan Department of Natural Resources on a wide range of topics important to those who enjoy and appreciate Michigan’s world-class natural resources of the Upper Peninsula.