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Black-billed Cuckoo

November 15, 2023

The Black-billed Cuckoo (Coccyzus erythropthalmus) is a captivating bird species that is relatively lesser-known among bird enthusiasts. In this educational blog, we will explore the size and shape, color pattern, behavior, habitat, and other essential aspects of this fascinating bird. By delving into the unique features of the Black-billed Cuckoo, we hope to provide a comprehensive understanding of this species, helping you appreciate its importance in our natural world.


Size and Shape

The Black-billed Cuckoo is a medium-sized bird with a slender body, measuring approximately 11-12 inches in length with a wingspan of around 15 inches. Its shape is characterized by a long tail, a somewhat flattened head, and a slightly curved, relatively short bill. This bird's legs are quite short, with zygodactyl feet – two toes pointing forward and two pointing backward – which allow it to cling onto branches with ease.

The wings of the Black-billed Cuckoo are rounded and broad, allowing for agile flight through the dense foliage of its preferred habitats. When perched, the long tail is typically held slightly drooping, giving the bird a distinctive silhouette. The overall shape of the Black-billed Cuckoo is well-suited for its lifestyle, which includes foraging and nesting in the thickets and woodlands.


Color Pattern

The Black-billed Cuckoo's color pattern is relatively subdued, with a primarily grayish-brown upper body and a pale gray to white underside. This muted coloration helps the bird blend into its surroundings, providing excellent camouflage. The head is adorned with a thin, white eyebrow stripe that contrasts with the dark eye and black bill, which gives the bird its name.

The long tail features white spots on the outer tail feathers, which are more apparent during flight or when the tail is fanned. Juvenile birds have a slightly different color pattern, with more extensive barring on the chest and a duller overall appearance. Despite its subtle coloration, the Black-billed Cuckoo's distinctive shape and markings make it easily recognizable to those familiar with the species.



Black-billed Cuckoos are primarily insectivorous, with a preference for caterpillars, especially those of hairy or spiny species that other birds may avoid. They also consume a variety of other insects, as well as small fruits and berries when available. Their foraging behavior consists of methodically searching through foliage, often hovering to snatch prey or pluck fruit from branches.

These birds are generally solitary or found in pairs during the breeding season. They are known for their secretive and elusive nature, often remaining hidden within dense foliage and only occasionally revealing themselves. The Black-billed Cuckoo is mostly active during the day but may also exhibit crepuscular or nocturnal behavior, especially during migration.

During the breeding season, males perform courtship displays that include wing and tail spreading, accompanied by soft, cooing vocalizations. The nest is a relatively flimsy platform of twigs, leaves, and grasses, usually built in a dense thicket or shrub. Both parents share incubation duties, and unlike some other cuckoo species, they raise their young without relying on other birds to do so.



The Black-billed Cuckoo inhabits a wide range of habitats across its range, which extends from southeastern Canada through the eastern United States and into Central America. It favors dense thickets, woodlands, and forest edges, with a particular preference for areas near water sources such as streams, swamps, or ponds. During migration, Black-billed Cuckoos can also be found in more open habitats, including scrublands and grasslands.

This species has a strong association with areas experiencing insect outbreaks, such as tent caterpillar or gypsy moth infestations. In years with high insect populations, Black-billed Cuckoos may be more abundant and widespread. Conversely, during periods with lower insect numbers, their populations can become more localized and harder to find.



  1. The Black-billed Cuckoo is known for its distinctive call, a series of soft, hollow "cu-cu-cu" notes, often heard at night or during overcast days.
  2. Unlike the more notorious brood parasitism of some cuckoo species, the Black-billed Cuckoo builds its nest and raises its young without relying on host species.
  3. The Black-billed Cuckoo can consume large quantities of hairy or spiny caterpillars, which may aid in controlling forest pest outbreaks.
  4. This bird species is known to be an effective long-distance migrant, traveling as far south as northern South America during the winter months.
  5. The population of Black-billed Cuckoos has declined in recent decades, likely due to habitat loss and fragmentation, as well as pesticide use affecting their insect prey.


Ecosystem Services

The Black-billed Cuckoo plays a crucial role in maintaining the health of forest ecosystems by controlling insect populations. As a voracious consumer of caterpillars, including those that can cause significant defoliation and damage to trees, the presence of Black-billed Cuckoos can help keep these pests in check. This natural pest control service not only benefits the forest ecosystem but also has positive implications for the timber industry and human populations that rely on healthy forests.

Additionally, the Black-billed Cuckoo serves as a prey species for various predators, including raptors, snakes, and mammals, thus contributing to the overall balance of the ecosystem. Its nesting habits also provide opportunities for other cavity-nesting species to reuse or modify the nesting sites in subsequent years.



The Black-billed Cuckoo is a fascinating bird species with a unique shape, color pattern, and intriguing behavior. While it may not be as well-known as some other bird species, its role as a natural pest controller highlights its importance within the ecosystems it inhabits. By understanding the various aspects of the Black-billed Cuckoo's life, we can work towards better conservation efforts to ensure this species continues to thrive and contribute to the health of our forests.