Current Newsletter

ven if I had no clock and no calendar, I could tell time these days by the birds. Most days and many nights I am outside more than in, and birds mark each hour, each month, each season in their own way.

Here where I am, cardinals open each winter morning, but when spring comes, the robins take over dawn for a time, then the mockingbirds as the weather warms toward summer. Chickadees, titmice, Carolina wrens, and cedar waxwings claim midmornings, backed by the cardinals, who only quiet when it’s dark. In the heat of the day, the male house finches, with their long tangle of song, sing from the tops of trees, while the mockingbirds do a selection of their greatest hits from rooflines and phone poles. (I treasure a question an English visitor asked me a few years ago: What’s yon bird that can‘t settle on a tune?)

Most birds are silent when I am out in the dark—excepting the mockingbirds, who use the quiet to their advantage, singing their hearts out to attract a mate.

There was also one bird last summer, hidden so deep in foliage I could never see her, pipping a note so strange that even Merlin, Cornell’s bird identification app, couldn’t name what she was. I heard her the first time in June of last year. A slow pip-pip-pip? Pip … pip… pip-pip-pip that seemed to echo, like she was beneath the deck, on the porch next door, or somewhere very close to the hard walls of the house. The one-note pips were tuneless, almost like the repeated chirp of a house fire alarm when its batteries are low.

The little bird note was intermittent, odd. If I made a noise on the porch, she pipped. If the wind blew, she pipped. If one of the dogs came outdoors, she pipped. Drowsy and relaxed, it seemed to be a little pip-pip-pip of situational awareness. I’m here. I’m aware of the world around me. But exactly where was she and who was she pipping to? A mate? Her babies? Me?

Pepita, the little rescue Chihuahua adopted last year, was particularly curious about her. She never barked when she came out with me, but she moved toward the sound, muttering small and low beneath her breath. It was Pepita who showed me where the sound originated, deep in the hydrangea bushes by the back door. She showed me again when a similar pip began sounding by the front porch, this time deep in the spireas that border the front of the house. Every time the bird would pip in the darkness, Pepita would stand on the back of the couch gazing out the window, nose pointing to the source of the pips as she understood it.

What was this bird making little pips in the dark? The Merlin app couldn’t help me. I made recordings that I posted online to no avail.

It took months for me to identify our little night pipsqueak, who gave herself away by sight, not sound. With Pepita’s guidance, I had marked two spots in the front and back of the house with stones. The night pips come from here.

And then I watched, by day, to see who was entering and exiting those spots. It took patience and a lot of stillness, not my greatest gifts, but one day I was rewarded by the flash of a Carolina wren landing on the front porch railing, then plunging into the spirea with a bug in her mouth. This was a mama I was hearing late at night, a nesting mama with babies underwing. A few days later, she emerged from the same spot, landed on a porch table, and gazed into the window at Pepita, gazing out. No fear on her part, no bark in response. It was a moment of curiosity and connection. Those mamas seemed to understand each other.

Not long afterward, another Carolina wren made her nest in an airplane plant farther back on the porch. She, too, pipped, but she also glared at me every time I passed. Don’t you even think about interfering here.

I didn’t.

But why the night pips?

I have since learned that Carolina wrens, like many other birds, have the gift of unihemispheric slow-wave sleep—meaning that one side of their brain can be wakeful while the other side sleeps. It allows birds to stay vigilant against predators and helps migrating birds fly without pause, one eye open and the corresponding hemisphere alert, while the other half of the brain sleeps.

Interestingly, not all birds do this, and the birds that do may not do it all the time. In flock species that sleep together for safety, the outermost birds may practice this one-sided sleep, while birds in the middle of the group shut both brain hemispheres down, sleeping both sides in the way humans do.

With no studies to back this up, my guess is that the nesting mama wrens in front of and behind the house are engaging in unihemispheric sleep, and that the awake part of their brains is responding to changes in the environment around them.

When the wind blows, the nest moves, and they pip. When I step out near their area, they pip. Are they comforting their young by saying I’m here or using the note as a caution of some sort? An alert to a mate? An acknowledgment to self?  I don’t know (yet) but the behavior is interesting. It’s also new to us here, probably because only now do we have foliage deep enough to safely shelter wren nests. When winter stripped the leaves last year I found them, small cups of twigs, leaves, and fluff, expertly braided. Those nests were full of snow, yet sturdy as ships, ready for summer and mama wrens to return.

© Susannah Charleson, 2026