June 8, 2025, Marias River, north-central Montana, USA. My headlamp lights up the deer trail ahead of me as I pick my way towards the Marias River through the dark pre-dawn badlands. I generally prefer to walk without a light, but the terrain is rough here. And I wouldn’t want to trip over a rattlesnake. I stop where the trail descends steeply into a narrow gully, listening. I turn off my headlamp. Rock wrens (Salpinctes obsoletus) sing from the eroded shadows of clay around me. The first hint of light is touching the northeastern sky.
It was the possibility of black-billed cuckoos (Coccyzus erythropthalmus) that brought me here, although I know the possibility is slim. In 2021, while Anna Fasoli was floating the river, she heard and recorded a singing cuckoo here. This is a bird that I’ve lived my whole life without encountering, a bird which a long-ago generation of nineteenth-century naturalists would observe descending on orchards in flocks to feed on caterpillars. Hardly anyone sees flocks of black-billed cuckoos now. Insecticides and habitat loss are thought to be to blame. To see a cuckoo at all, at least in Montana, is a rare encounter that takes a lot of effort, a lot of luck, or both. But the decline of black-billed cuckoos, like almost every aspect of their biology, remains shrouded in unknowns. And so here I am, listening to rock wrens in a dark badlands gully, bound for the river and imagining cuckoos.
From the badlands to the cottonwoods
Last night, I camped high at the end of an access road on a wide bench above the badlands. Grasshopper sparrows (Ammodramus savannarum) serenaded me from unbroken grassland as I cooked ramen soup with milkweed (Asclepias speciosa) flower buds by headlamp over my little gas stove. Tiny biting midges tormented me, followed me into my car, and even managed to sneak into my tent.
I woke (reluctantly) at 4:00 am and was ready to go by 4:20—backpack, headlamp, snacks, birding gear, bear spray. And now rock wrens sing from the wrinkles of the badlands, and the cottonwood forest beckons below.
The northern house wrens (Troglodytes aedon) have begun singing by the time I reach the edge of the cottonwoods. A great horned owl (Bubo virginianus) hoots just once in the distance. The creatures of the night are giving way to the dawn chorus. An abandoned homestead weathers slowly into elegant oblivion at the edge of the trees. The shed sags to the north, defeated, but the old bones of the two-story house remain strong. I walk gingerly among fallen boards with rusty nails and peek inside, hoping wildly that an American barn owl (Tyto furcata) might be roosting. But all I find is a rusting box spring and an old galvanized wash tub. An eastern kingbird (Tyrannus tyrannus) gives his electrical call from a branch level with a gaping second-story window frame. The air is thick with stories.
Habitat for black-billed cuckoos
Continuing on, I pass a white-tailed deer (Odocoileus virginianus) bedded down with her spotted fawn. She watches me with mild concern and I veer far around, leaving them undisturbed.
I’m at the edge of a massive cottonwood stand now, old trees with fissured bark. Most are narrowleaf cottonwoods (Populus angustifolia), with some broader-leaved Plains cottonwoods (Populus deltoides) mixed in. An old, dry river oxbow curves through the trees, and in places along it there’s a nice understory of chokecherry (Prunus virginiana) thickets. A gray catbird (Dumetella carolinensis) sings as a migrating Swainson’s thrush (Catharus ustulatus) gives his harmonic whistles from the undergrowth. To my untrained eye, this looks like good black-billed cuckoo habitat, as I understand it: an extensive deciduous forest with a shrubby understory, far away from insecticides. But I hear no cuckoo.
Where are the cuckoos?
Is it too early yet? Cuckoos arrive in Montana quite late in the spring, traveling from their poorly known South American winter range, apparently somewhere between Colombia, Venezuela, and Bolivia. Birds of Montana reports them showing up here in early to mid June—now, that is. Still, it seems to me that spring arrival dates for many birds have been a bit delayed this year. Perhaps the cuckoos just haven’t gotten here yet.
Of course, there are other possibilities. The specter of declines and all that is unknown hangs over them. There’s a lot that is unknown. Where exactly do they spend the winter? What are the paths of their migrations? How do they find outbreaks of the tent caterpillars and cicadas they seem to be so fond of eating? And will they come back to the Marias River, where they sang in July 2021? I think about all of the things that have to go right for them to make it back. There are too many possible tragedies: insecticides, the loss of an important habitat somewhere in their annual journey, window collisions, outdoor cats…
And then, of course, a cuckoo might be hiding in the chokecherry bush 15 feet away from me! If it’s not singing, I could very easily miss it.
The forest
I continue walking. The forest stretches for hundreds of acres. In some patches the trees are big and old; closer to the river, I find middle-aged stands and young cottonwood saplings. In the distance, I hear a beaver slap its tail once, alarmed at something. Western wood-pewees (Contopus sordidulus) and least flycatchers (Empidonax minimus) sing from the canopy and I’m surprised to hear a few yellow-headed blackbirds (Xanthocephalus xanthocephalus) in the distance—evidently there is a wetland slough on the other side of the river.
I start wondering how I can manage a second visit, in case it’s still too early in the season for cuckoos.
A coyote slips away from me as I follow fresh deer tracks along a river meander with some moisture in the bottom, growing up with sandbar willows (Salix exigua). A common yellowthroat (Geothlypis trichas) sings.
June exuberance
I find myself filled with gratitude that places like this still exist. A huge floodplain, a rich cottonwood habitat with multiple-aged trees, shrub patches, and wetlands. A home for many creatures, sculpted by floods and beavers, by cottonwood fluff on the June breeze, by a million relationships and interactions. It’s not pristine—the understory in many places is dominated by smooth brome (Bromus inermis), an invasive grass. And who knows if the cuckoos will come back. But in spite of everything, it’s bursting with life.
I think about all the unfathomable generations of life on earth. All of this June exuberance, millions of years of it, hangs in the air. I try to imagine the sounds and happenings of early June on this land in the time of the dinosaurs, whose bones lie fossilized on these plains.
Life goes on
It’s bittersweet comfort to me to think that if we follow the fate of the dinosaurs, as we seem so perilously hell-bent on doing, life in some permutation will continue here. The smooth brome that the land managers ignore and the leafy spurge (Euphorbia esula) that they attack with herbicides will become part of the ecology of this place. With time, presumably, native insects will evolve to make greater use of these abundant new plants, these human introductions to the North American continent. The homestead will be long-gone, boards into dust, rusty nails buried beneath spring floods. Will the black-billed cuckoos come back? That is anyone’s guess.
The drumming of a red-naped sapsucker (Sphyrapicus nuchalis) pulls me out of my extinction musings. He’s close but just out of sight. Then he flies into the cottonwood right next to me, playing the resonant wood of a dead branch. He makes me think of the sapsuckers in the pileated woodpecker forest near Missoula, how they drum so frequently when they first arrive in April but become almost silent by this time. Is this a sapsucker that hasn’t found a mate, still diligently tapping away on the woodpecker equivalent of Tinder? I wonder if, like in Missoula, the late-April soundscape here is filled with sapsucker drumming.
Listening for cuckoos
I continue listening for a black-billed cuckoo. Nothing. A male black-headed grosbeak (Pheucticus melanocephalus) sings from the very highest branch of a cottonwood, not hiding himself frustratingly in the foliage this time like they often do. For the cuckoos, some birders would bring a portable speaker and blast the cucucu song, trying to get a bird to respond. Outside of limited use for formal biological surveys, I prefer not to do that, so I’m just doing passive listening. If a cuckoo sings today, it will be because it wants to.
The morning is warming up and a breeze has started rustling the cottonwood leaves. Northern house wrens continue singing, and the distant whistles of the western meadowlarks (Sturnella neglecta) echo against the badlands. The air is getting a yellow tinge as smoke rolls in from the once-unheard-of spring wildfires that are raging once again across the Canadian boreal forest.
No cuckoos. Some people might see it as a wasted morning: I went searching for something and didn’t find it. But I hope I get to waste many more mornings like this, contemplating millions of years of June exuberance along a wild river. And I hope the cuckoos come back.
P.S. More about cuckoos!
I am delighted to announce that in the upcoming months I’ll be sharing a second story about the mysterious lives of cuckoos featuring Anna Kurtin, who recently completed her Master’s degree in Wildlife Biology at the University of Montana. Anna has spent the past three years learning about black-billed cuckoos, effective ways of studying them, and which habitats they use in Montana. I’m excited to delve more deeply into cuckoo biology with her. Stay tuned!
More resources
eBird Basic Dataset. Version: EBD_relJun-2025. Cornell Lab of Ornithology, Ithaca, NY. June 2025.
Hughes, J.M. (2020). Black-billed cuckoo (Coccyzus erythropthalmus), version 1.0. In Birds of the World (A.F. Poole, editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://birdsoftheworld.org/bow/species/bkbcuc/cur/introduction
Marks, J.S., Hendricks, P. & Casey, D. (2016). Birds of Montana. Arrington, VA: Buteo Books.