It was the possibility—slim though it was—of black-billed cuckoos (Coccyzus erythropthalmus) that brought me to the Marias River. 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. 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.

This month’s story will immerse you in a world at the river’s edge that black-billed cuckoos inhabited—and do they still? The podcast includes many of my natural sound recordings: rock wren (Salpinctes obsoletus), northern house wren (Troglodytes aedon), great horned owl (Bubo virginianus), grasshopper sparrow (Ammodramus savannarum), eastern kingbird (Tyrannus tyrannus), gray catbird (Dumetella carolinensis), Swainson’s thrush (Catharus ustulatus), western wood-pewee (Contopus sordidulus), least flycatcher (Empidonax minimus), yellow-headed blackbird (Xanthocephalus xanthocephalus), red-naped sapsucker (Sphyrapicus nuchalis), and black-headed grosbeak (Pheucticus melanocephalus). As well as the alarm sound of a beaver (Castor canadensis). In other words, it’s a journey among a sea of sounds from the riparian zone! 

As always, I depend on the support of my listeners to continue doing this work. Please share these podcasts, leave a rating, and, if you’re able, support me through Patreon: https://www.patreon.com/wildwithnature. Thank you!!!

You can find the written, illustrated version of this story here: https://wildwithnature.com/2025/08/01/how-to-not-find-black-billed-cuckoos/