Nature: Brood X will bring out black-billed and yellow-billed cuckoos who feast on cicadas

 

A black-billed cuckoo in northern Michigan, where it is common/Jim McCormac

Nature: Brood X will bring out black-billed and yellow-billed cuckoos who feast on cicadas

The Columbus Dispatch
May 30, 2021

NATURE
Jim McCormac

In my last column, I wrote about the impending eruption of Brood X 17-year cicadas. They’re in full cacophonous swing now. If you live in an emergence area, you know. Depending on one’s outlook, the cicadas are annoying pests or a rare opportunity to witness one of nature’s greatest entomological spectacles.

The black-billed cuckoo would take the latter viewpoint. Cuckoos are voracious cicada predators and take full advantage of emergences such as Brood X.

Cuckoos are fascinating and poorly understood birds. Two species occur in Ohio: the aforementioned black-billed cuckoo, and the more common and wide-ranging yellow-billed cuckoo. Although they look like songbirds, cuckoos do not belong to the giant order Passeriformes, which includes songbirds. They are much more closely related to owls.

While yellow-billed cuckoos nest commonly statewide, black-billeds are most frequent in the northern third of the state, but even there are outnumbered by the former.

Brood X should turn that distribution and abundance status on its ear this year. Black-billed cuckoos — yellow-billeds, too — converge on cicada emergences in big numbers. It’s as if the birds have their own Nextdoor app to clue them in. The mechanisms that allow them to locate cicada emergences is not understood.

One would think that a bird that’s bigger than a robin would be easy to study. Not so. Cuckoos are quite secretive and given to skulking in dense vegetation. Their loud, distinctive calls are often the only evidence of their presence.

Even at the late spring date of this column, cuckoos are still arriving. They have a long trip to get here. Black-billed cuckoos winter in western South America, from Colombia south into Peru. Next to nothing is known of cuckoos in their tropical haunts.

In 2016, when periodic cicada Brood V emerged over much of eastern Ohio, I was stunned at cuckoo numbers. It seemed that everywhere I stopped, cuckoos of both species would be calling. In areas where the black-billed cuckoo would normally be unusual, they were commonplace.

Billions of easily captured, six-legged flying steaks make for easy pickings, and small wonder cuckoos capitalize on the bounty. They are well-known for exploiting caterpillar outbreaks, too, and when food is plentiful breeding success spikes.

Food outbreaks can trigger an unusual behavior in cuckoo reproduction: brood parasitism. Ample nutrition allows female cuckoos to produce an excess of eggs. They’ll dump some in other birds’ nests, in the hopes that the unwitting hosts will raise the cuckoos. Host species include American robin, chipping sparrow and gray catbird. Sometimes even yellow-billed cuckoos fall victim.

Our cuckoos seemed to have evolved with insect booms, especially those of caterpillars and cicadas. Feathered nomads, they congregate where the outbreaks occur. Unfortunately, natural insect cycles are not what they used to be.

Naturalists described “flocks” of cuckoos descending on insect emergences in the late 1800s. No one sees such numbers these days — there are far fewer cuckoos. Ill-devised “pest” management and massive alterations to forested habitats have wrought havoc on natural insect cycles, including periodic cicadas. The animals that evolved to exploit these booms, thus providing natural controls, have also been greatly reduced in number.

But for cuckoos in the Brood X zone there will be food aplenty, and hopefully scores of little cuckoos will result.

Naturalist Jim McCormac writes a column for The Dispatch on the first, third and fifth Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com.

Cuckoos have come back from far southern climates

COLUMBUS DISPATCH

July 5, 2015

NATURE

Jim McCormac

…He was but as the cuckoo is in June, Heard, not regarded…

William Shakespeare (from Henry IV)

On a recent photographic foray to Glacier Ridge Metro Park, I had an amazing experience with one of our most enigmatic birds.

While in a meadow admiring bobolinks, I heard the loud junglelike call of a yellow-billed cuckoo. The bird was secreted within an isolated grove of trees. As I neared my quarry, it dropped from thick cover and headed across the meadow.

I issued my best cuckoo imitation, which caused the bird to pivot and return to the trees, giving me beautiful photo ops. In short order, it snapped off a twig and took it to a nesting site.

Yellow-billed cuckoos (and our other species, black-billed cuckoos) are far easier to hear than see. Although large — the size of a mourning dove — cuckoos typically remain concealed in dense leafy cover.

Cuckoos are late migrants, with many not arriving until early June. They have come a long way: Almost all spend the winter in South America.

One reason for the tardy return is their prey. Caterpillars, especially large ones, form cuckoos’ dietary staple. It’s best for the cuckoos to wait until the caterpillar crop matures before arriving to feast upon them.

To the caterpillar, having a cuckoo in the tree is akin to Freddy Krueger entering the house. Cuckoos are adept at locating caterpillars and making mincemeat of them. This is one of few birds that eat the hairy Eastern tent caterpillars that form silken nests in cherry trees. A ravenous cuckoo was documented downing 47 of these larvae in six minutes.

Cicadas are also a favored food. The emergence of periodical cicadas can stimulate localized booms in cuckoo populations. Much of eastern Ohio will experience a 17-year cicada emergence next year. There should be lots of cuckoos to exploit the bounty.

Cuckoos can become nest parasites. In addition to raising its own young, a female cuckoo might drop eggs in other birds’ nests. The unwitting surrogates then raise the cuckoos. Common hosts include catbirds, robins and wood thrushes.

It takes only 17 days for a cuckoo to go from egg to fledgling.

Naturalist Jim McCormac writes a column for The Dispatch the first and third Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com