The Sumatran ground cuckoo (''Carpococcyx viridis'') is a large, terrestrial species of

cuckoo Cuckoos are birds in the Cuculidae ( ) family, the sole taxon in the order Cuculiformes ( ). The cuckoo family includes the common or European cuckoo, roadrunners, koels, malkohas, couas, coucals, and anis. The coucals and anis are somet ...

endemic to the forests of

Sumatra Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi. ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

. It was first described in 1879 and, despite being identified as a separate species in the 1880s, was formerly considered

conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organism ...

with the Bornean ground cuckoo until recently being returned to the status of a unique species. Considered a

critically endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

species by the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

, it was initially known from just eight specimens and evaded notice from 1916 until 1997, when it was rediscovered and photographed. The Sumatran ground cuckoo's diet is thought to consist of invertebrates, small mammals, and reptiles.

Description

The Sumatran ground cuckoo is a large bird of about in length. Its wings and long, full tail are glossy greenish-black, while its mantle, upper back, neck sides, lower throat, upper breast,

covert feathers A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts The ear coverts are small feathers behind t ...

, and

secondary feathers Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the Bird wing, wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those ...

are dull green. Its crown is black, and the bare skin around its

eyes An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system. In higher organisms, the ey ...

are hues of green, lilac, and blue. Its bill and legs are green, and its underparts below the upper breast are cinnamon buff.

BirdLife International BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding i ...

describes its voice as follows: "Repeated low whistles (falling then rising in tone: WE-ow-WE), plus issued in a rising series (''we-ow-we'', ''we-ow-we'', ''we-ow-we'', ''we-ow-we''; each phrase slightly higher than last)."

Distribution and habitat

The Sumatran ground cuckoo is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the

n island of

. Notes on early specimen labels as well as recent sightings suggest its favoured habitat is foothills and primary

montane Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures lapse rate, fall as elevation increases, causing the ecosystem to stratify. This stratification is ...

forest. It has been found between elevations of , although recent sightings are exclusively from . Its small population makes it difficult to find, and like the Bornean ground cuckoo, it may exhibit unobtrusive behavior – making sightings even more rare. Most modern-day sightings have taken place in the

Barisan Mountains The Bukit Barisan or the Barisan Mountains are a mountain range on the western side of Sumatra, Indonesia, covering nearly 1,700 km (1,050 mi) from the north to the south of the island. The Bukit Barisan range consists primarily of volca ...

South Sumatra South Sumatra () is a Provinces of Indonesia, province of Indonesia, located in the southeast of the island of Sumatra. The capital and largest city of the province is the city of Palembang. The province borders the provinces of Jambi to the north ...

and the Kerinci Seblat National Park of

Jambi Jambi is a province of Indonesia. It is located on the east coast of central Sumatra Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of i ...

province, beginning with an individual photographed in Bukit Barisan Selatan National Park in 1997. An additional unconfirmed sighting took place in the Bukit Rimbang-Baling Wildlife Sanctuary in 2000. In 2006, a

camera trap A camera trap is a camera that is automatically triggered by motion in its vicinity, like the presence of an animal or a human being. It is typically equipped with a motion sensor—usually a passive infrared (PIR) sensor or an active infrared ...

surveying for tigers close to Kerinci Seblat National Park, also in the Barisan Mountains, captured multiple images of the Sumatran ground cuckoo for the first time since 1997 and only the second time in the last ninety years. In 2007, its call was recorded for the first time by

Wildlife Conservation Society The Wildlife Conservation Society (WCS) is a global 501(c)(3) organization, 501(c)(3) non-governmental organization, headquartered at the Bronx Zoo in New York City, with a mission to save "wildlife and wild places across the globe". Founded in ...

biologists after a trapper handed them a bird he had caught. Up to five more sightings were reported nearby between 2007 and 2010. In 2017, a camera trap in Batang Gadis National Park took a photo of a Sumatran ground cuckoo, indicating that a previously unknown population may exist in

North Sumatra North Sumatra () is a Provinces of Indonesia, province of Indonesia located in the northern part of the island of Sumatra. Its capital and largest city is Medan on the east coast of the island. It borders Aceh to the northwest, Riau to the sou ...

Status and conservation

Due to ongoing habitat loss and small population size, the

evaluates the Sumatran ground cuckoo as

. The Red List estimates that the total population of Sumatran ground cuckoos ranges from 50 to 249 mature individuals, and its population is thought to be decreasing. The bird's known range overlaps with some of the

' 20 protected areas, but rapid

deforestation Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...

– its main threat – is prevalent even in these areas. A 2003 study showed an average 2% loss of forest within Bukit Barisan Selatan National Park, part of its known range, between 1985 and 1999. This deforestation is caused predominantly by logging, palm oil plantations,

pulpwood Pulpwood can be defined as timber that is ground and processed into a fibrous pulp. It is a versatile natural resource commonly used for Papermaking, paper-making but also made into low-grade wood and used for chips, energy, pellets, and engineered ...

plantations, establishment of farms, and

wildfire A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a ...

s. As the Sumatran ground cuckoo prefers primary forest with dense undergrowth, reforestation is unlikely to be as effective as protective measures for currently existing habitat. The species likely benefits from protected areas, but its conservation needs are not fully understood due to a lack of study.

References

Works cited

* *

External links

Tiger trap goes cuckoo
article at BirdLife International * * {{Taxonbar, from=Q604404 Sumatran ground cuckoo Endemic birds of Sumatra Critically endangered fauna of Asia Sumatran ground cuckoo Taxa named by Tommaso Salvadori