By Dan Zarlenga, Missouri Department of Conservation
Photo caption: Yellow-billed cuckoos truly do have crazy-sounding calls!
Photo by Jim Rathert, Missouri Dept. of Conservation.
This time of year, you might find yourself encountering a cuckoo. No, not a silly or foolish person. And not a cartoon character on a cereal box. Yellow-billed cuckoos—the real bird—can be found right here in Missouri. In fact, they begin nesting in the Show-Me-State this month.
But you might have to look hard to find one. Yellow-billed cuckoos are notorious for being especially shy and secretive. The best places to look are deciduous forests and woods, particularly if they happen to be near water.
Should you catch a glimpse of one, you’ll notice a slender, two-toned bird, with dark brown on top and a solid line of transition to whitish below. They feature rusty patches on their wings and distinct white spots on their tails. And yes, their curved bills are indeed tinged with yellow underneath.
What you’re far more likely to detect though, is the yellow-billed cuckoo’s unique vocalizations. The bird’s call is described as “knocking”. It’s a stuttering, staccato sound that can be startling to hear—you’d think the bird might have an ultra-serious case of the hiccups. Cornell Lab or Ornithology describes the sound as ka ka-ka-ka-ka-kow-kow-kowlp-kowlp-kowlp-kowlp.
Cuckoos have also been known to give their calls in response to other loud sounds, such as thunder. Some people call them “rain crows”. Add to this the fact that cuckoos are just as likely to sound off at night as during the day, and you have one unusual caller. Their song on the other hand is a bit less unusual, being a sharp, short, coo.
Yellow-billed cuckoos migrate from South America to the United States in spring to breed. They nest in Missouri during May. Female cuckoos have an interesting behavior of not laying all their eggs at once. They practice asynchronous egg laying, meaning the mother will wait a while between laying each egg. This might be as much as five days between eggs.
As the chicks hatch one-by-one, they will develop at different rates; the earliest to hatch are about ready to leave the nest as the latest ones are just emerging from the egg. This helps spread the burden of feeding out more by not having all the offspring needing to be fed at once. You might think of it as a conveyor belt, or assembly-line rearing. It’s a survival mechanism some other bird species practice as well.
Young, yellow-billed cuckoos develop with assembly-line efficiency too. They have one of the shortest nesting cycles of any bird species. Incubation to fledging can happen in as little as 17 days. Although born featherless, the young mature very quickly. The chicks grow their feathers and leave the nest just a week after hatching. Youth is truly short for yellow-billed cuckoos!
The yellow-billed cuckoo’s favorite food is caterpillars. They especially love tent caterpillars, and webworms. Thankfully cuckoos will also munch down on spongy moths (formerly called gypsy moths), especially in eastern states where those destructive, invasive insects are a real problem.
So, if you’re passing by the woods and find yourself startled by a strange, stuttering sound echoing in the trees like uncontrollable hiccups, don’t be concerned. You’re not crazy. You’ve just encountered a cuckoo.