Photo: Yellow-billed Cuckoo, Kelly Colganazar
Bird of the Month: Fall Migration Brings Cuckoos to Virginia
By Jessica Biggers
When you hear “ka-ka-ka-ka-ka-kow-kow-kowlp-kowlp-kowlp-kowlp” or a mellow “cu, cu, cu, cu” call in the distance it might be a sign of rain. Because of the Yellow-billed Cuckoo’s (Coccyzus americanus) and the Black-billed Cuckoo’s (Coccyzus erythropthalmus) weather forecasting abilities, they are commonly known as the “rain crow.” As a rain storm is blowing in, our little friends are giving us a heads up to run for cover. These elusive birds are rarely seen but heard, and their song and call can carry quite a distance. They are also long-distance migrants flying silently to their destination.
Sometimes Yellow-billed and Black-billed Cuckoos get a bad rap, being compared to their close cousin the Common Cuckoo from Eurasia. The Common Cuckoo is a brood parasite whose call is mimicked by a cuckoo clock’s chime. Although, Yellow-billed and Black-billed Cuckoos will occasionally lay their eggs in other birds’ nest, it is not a common occurrence. In most cases, if they do, they will lay their eggs in other cuckoo’s nests.
Even though both Yellow-billed and Black-billed Cuckoos can lay up to two broods, they tend to only raise one and don’t lay their eggs all at once, but asynchronously. Youngsters, when threatened, will make a display similar to a bittern, where they stretch their necks, with their heads looking straight up into the sky; standing like a statue.
Yellow-billed Cuckoos (YBCU) and Black-billed Cuckoos (BBCU) migrate through Virginia in the spring. But Black-billed Cuckoos breed farther north from Virginia while Yellow-billed Cuckoos have a more expansive breeding territory. In seasons when there is an abundance of caterpillars and cicadas, you’ll tend to hear and see more of them. YBCU’s have a preference for tent caterpillars, gypsy moths and cicadas, while BBCU munch on caterpillars of the spiny variety, shedding their stomach lining to remove the spines and coughing those spines up into owl-like pellets.
While our eastern Yellow-billed Cuckoo’s population is stable, the western population is struggling due to habitat loss. They inhabit woodlands, thick brush, marshes and abandoned farmland. Black-billed Cuckoos live more in woodlands and thickets.
This year, I’ve seen a ton of spiny and tent caterpillars, more than in past years. Plus, we’ve had a lot of rain. So, there is a good chance we’ll hear more of these elusive birds during fall migration as they head down to Mexico and Central American for the winter.
Sources:
https://web.stanford.edu/group/stanfordbirds/text/essays/Brood_Parasitism.html
https://www.audubon.org/birds-of-america/yellow-billed-cuckoo