The Louisiana rain crow of my youth was the yellow-billed cuckoo. Here we have two cuckoos, the yellow-billed and black-billed, with the yellow-billed being far more common.
They are similar in sight and sound. The cuckoos are slender long-tailed birds just a bit larger than mockingbirds. They are rusty-brown on top and white below. The yellow-billed has a yellow lower mandible while the black-billed has a totally black bill. The yellow-billed also shows a rufous patch near the end of the wings, absent in the black-billed and it has more prominent white spots in the tail than the black-billed. The song of the yellow-billed is a rapid series of ka-ka-ka-kow-kow-kowlp-kowlp-kowlp that slows towards the end. It will often make only the kowlp-kowlp-kowlp call with a mourning dove kind of quality. The black-billed’s call is a fast cucucucu-cucucucu-cucucucu-cucucucu often grouped in threes or fours. It will occasionally also give a static kow-kow-kow-kow note. Don’t be fooled in the autumn by a chipmunk.
These New World cuckoos aren’t nearly as nefarious as the Old World group that deposit their eggs – cowbird style – in the nests of other birds to raise. While the New World cuckoos occasionally drop an egg here or there, for the most part they raise their own brood.
The yellow-billed and black-billed cuckoos are neotropical migrants. They are one of our latest spring migrants and have developed a unique nesting strategy in order to brood and fledge progeny capable of making the fall migration to their South American wintering grounds.
The cuckoos have the shortest nesting cycle of any bird, going from egg laying to fledged in just 17 days. They appear to time their nesting cycle to coincide with caterpillar outbreaks. This provides a rich source of nutrients for parents and for the chicks, which are among the heaviest of North American songbirds at birth. These chicks need to be well developed and well fed because they will be headed south within a month.
For cuckoos there’s no such thing as a noxious caterpillar. Foul tasting monarch caterpillars and spiny gypsy moth caterpillars are gulped as voraciously as any others. One might think that all those hairs and spines could wreak havoc in a cuckoo’s stomach – well it does. But no problem – the cuckoo simply sheds that stomach lining, spines and all, grows a new one and keeps on chomping caterpillars. One observer watched as a cuckoo devoured 41 gypsy-moth caterpillars in 15 minutes and noted another bird ate 47 tent caterpillars in six minutes.
Sadly, cuckoos have declined across their range in North America. Breeding bird statistics from eastern states have shown an average decline of more than 50 percent across 14 of the 29 states with enough data to be statistically valid. Loss of habitat is the greatest culprit regarding the decline. Cuckoos are on the Audubon list of species of concern and there are efforts to have the birds listed federally.
I know there would be an empty spot in my soul where the sound of the rain crow lives now if I had never encountered it as I tromped along that dusty road around Horseshoe Lake. I hope it’s a spot that’s full in my grandchildren’s souls.