What do they look like?

Yellow-billed cuckoos are medium birds with long tails. They are 26 to 30 cm long and weigh 55 to 65 g. They have grayish brown heads and backs and dull white underparts. Their tails are long and have two rows of large white circles on the underside. Yellow-billed cuckoos have a curved bill with a black upper mandible and a yellow or orange lower mandible. On each foot, two toes point forward, and two toes point backward. This is called zygodactylous feet.

Female yellow-billed cuckoos are a little bit bigger than males. Young cuckoos look like adults, but are more reddish-brown on their wings. Also, the tail spots on young cuckoos are less clear.

Where in the world do they live?

Yellow-billed cuckoos are found in the Nearctic and Neotropical regions. They breed throughout eastern North America, in southeast Canada, northern Mexico and the Greater Antilles. They winter primarily in South America (Peru, Bolivia and northern Argentina).

What kind of habitat do they need?

Yellow-billed cuckoos live in open areas with some trees and dense shrubs. They are often found near streams, rivers or lakes. In North America, they live in habitats such as old farms and fruit orchards, shrubby fields and thickets. In winter, yellow-billed cuckoos live in tropical habitats with dense shrubs, such as scrub forest and mangroves.

How do they reproduce?

Yellow-billed cuckoos are probably monogamous (one male with one female). Breeding pairs form in May or June. A pair may visit many locations together before deciding where to build their nest. Males try to attract a female by offering her food or sticks and other nest materials.

Yellow-billed cuckoos begin breeding in mid- to late-May. Most cuckoos breed once per year, though some may raise two broods in one breeding season. The male and female parents work together to build the nest, which is made of twigs, roots, dried leaves and pine needles. The female may begin laying eggs before the nest is complete. She lays 1 to 5 (usually 2 or 3) light blue eggs, and begins incubating after the first egg is laid. Both parents incubate the eggs, which hatch after 9 to 11 days.

Yellow-billed cuckoo chicks are helpless when they hatch. The parents must brood them for the first week or so. Both parents also feed the chicks. The chicks begin to leave the nest after 7 to 9 days. They begin to fly when they are about 21 days old. The male parent usually takes care of the first chick that fledges, and the female parent takes care of the rest of the chicks (Ehrlich et al.). We do not know when yellow-billed cuckoo chicks become independent from their parents. Most yellow-billed cuckoos begin breeding when they are 1 year old.

Some yellow-billed cuckoos may parasitize other birds by laying eggs in the nest of other parents. They may lay eggs in the nest of other yellow-billed cuckoos, or in the nests of other bird species, including black-billed cuckoos, American robins, gray catbirds and wood thrushes.

Male and female yellow-billed cuckoo parents incubate the eggs, brood and feed the chicks and protect the nest from predators. They also keep the nest clean by removing the fecal sacs from the chicks. After chicks have left the nest, the parents keep feeding them until they are able to hunt for themselves.

How long do they live?

Yellow-billed cuckoos can live to be at least 4 years old in the wild.

How do they behave?

Yellow-billed cuckoos are solitary or live in pairs during the breeding season. They may be territorial.

Yellow-billed cuckoos are migratory. They migrate at night in small groups or large flocks. Yellow-billed cuckoos are generally active during the day (diurnal).

How do they communicate with each other?

Yellow-billed cuckoos use calls to communicate. They are usually silent birds during the winter and migration. However, during the breeding season, they call often to communicate with their mate and their chicks. These birds are able to make at least 6 sounds, which they use to communicate many different things.

What do they eat?

Yellow-billed cuckoos primarily eat large insects including caterpillars (order Lepidoptera), katydids, cicadas (family Cicadidae), grasshoppers and crickets (order Orthoptera). They also occasionally eat bird eggs, snails, small vertebrates such as frogs (Order Anura) and lizards (suborder Sauria) and some fruits and seeds. Parents feed their chicks regurgitated insects (Ehrlich et al.).

What eats them and how do they avoid being eaten?

Adult yellow-billed cuckoos are killed by raptors, including Aplomado falcons (Falco femoralis) and red-shouldered hawks (Buteo lineatus). They have also been eaten by a tiger shark (Galeocerdo cuvier). Nestlings and eggs are eaten by snakes such as the black racer (Coluber constrictor), small mammals such as eastern chipmunks (Tamias striatus), and birds such as blue jays (Cyanocitta cristata) and common grackles (Quiscalus quiscula).

When a predator is nearby, yellow-billed cuckoos hide themselves among vegetation and stand very still. If a predator is near their nest, parents either attack the predator or try to get the predator away from the nest by flying away and performing a distracting display and calling.

What roles do they have in the ecosystem?

Yellow-billed cuckoos affect the insect species that they eat. They provide habitat for many different species of parasites.

Yellow-billed cuckoos are nest parasites. Sometimes they lay their eggs in other birds’ nests. When this happens, the other birds’ chicks may suffer because there are too many chicks in the nest.

Do they cause problems?

There are no known adverse affects of yellow-billed cuckoos on humans.

How do they interact with us?

Yellow-billed cuckoos may help to control populations of pest insects.

Are they endangered?

Yellow-billed cuckoos are protected under the U.S. Migratory Bird Act. They are threatened or endangered in many states. Yellow-billed cuckoos are common in some areas. However, in many areas they are becoming less common because the shrubby habitats that they like are being destroyed or changed. Some cuckoos also die by being poisoned by pesticides or by crashing into towers or tall buildings during migration.

Contributors

Megan Hilt, University of Michigan

Contributors

Kari Kirschbaum, Animal Diversity Web Staff

References

Eaton, Stephan. 1997. Notes on the Reproductive Behavior of the Yellow-billed Cuckoo. The Wilson Bulletin. Vol. 19, No. 1:154-5. March.

Ehrlich, Paul R., David S. Dobkins and Darryl Wheve. 1988. The Birder's Handbook. Simon and Schuster, Inc., New York. p.286.

Fleischer, Robert C., Michael T. Murphy and Lawrence E. Hunt. 1985. Clutch Size Increase and Intraspecific brood parasitism. The Wilson Bulletin. Vol. 97, No.1:125-7. March.

Franzreb, Kathleen E. and Stephan A. Laymon. 1993. A Reassessment of the Taxonomic Status of the Yellow-billed Cuckoo. Western Birds. Vol. 24: 17-28.

Lasley, Greg W. and Chuck Sexton. 1985. South Texas Region. American Birds. Vol 39: 933-36.

Laymon, Stephan A. and Mary D. Halterman. 1987. Can the Western Subspecies of the Yellow-billed Cuckoo be Saved from Extinction. Western Birds. Vol. 18, No.1: 19-25.

Parker, Sybil P., ed. 1982. Synopsis and Classification of Living Organisms. Vol. 2: 988-989. McGraw-Hill Inc., New York. pp.988-989.

Allaby, Michael, ed. 1985. The Oxford Dictionary of Natural History. Oxford University Press, Oxford. pp.148.

Wolfe, Donald H. 1994 Yellow-billed Cuckoo Hatched in Mourning Dove Nest. Bulletin of the Oklahoma Ornithological Society. Vol XXVII, No. 4: 29-30. December.

Hughes, J. 1999. Yellow-billed cuckoo (Coccyzus americanus). Pp. 1-28 in A. Poole, F. Gill, eds. The Birds of North America, Vol. 418. Philadelphia, PA: The Birds of North America.