The Galapagos crake (''Laterallus spilonota''), also called the Galapagos rail and Darwin's rail, is a
Vulnerable species
A vulnerable species is a species which has been Conservation status, categorized by the International Union for Conservation of Nature as being threatened species, threatened with extinction unless the circumstances that are threatened species, ...
of
rail
Rail or rails may refer to:
Rail transport
*Rail transport and related matters
*Rail (rail transport) or railway lines, the running surface of a railway
Arts and media Film
* ''Rails'' (film), a 1929 Italian film by Mario Camerini
* ''Rail'' ( ...
in subfamily Rallinae of family
Rallidae
The rails, or Rallidae, are a large cosmopolitan family of small- to medium-sized, ground-living birds. The family exhibits considerable diversity and includes the crakes, coots, and gallinules. Many species are associated with wetlands, althoug ...
, the rails, gallinules, and coots. It is
endemic
Endemism is the state of a species being found 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 found elsew ...
to the
Galápagos Islands
The Galápagos Islands (Spanish: , , ) are an archipelago of volcanic islands. They are distributed on each side of the equator in the Pacific Ocean, surrounding the centre of the Western Hemisphere, and are part of the Republic of Ecuador ...
.
[HBW and BirdLife International (2021) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 6. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v6_Dec21.zip retrieved 7 August 2022][ It resembles its ]sister species
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and t ...
, the black rail of the Americas
The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World.
Along with th ...
, from which it diverged 1.2 million years ago.
Taxonomy and systematics
The Galapagos crake was originally described as ''Zapornia spilonota'' and has been moved among at least five other scientific names before its current binomial
Binomial may refer to:
In mathematics
*Binomial (polynomial), a polynomial with two terms
* Binomial coefficient, numbers appearing in the expansions of powers of binomials
*Binomial QMF, a perfect-reconstruction orthogonal wavelet decomposition
...
was adopted. At least one author classified it as a subspecies of black rail, and others consider the black rail and Galapagos crake to form a superspecies.[Hill, E. (2020). Galapagos Rail (''Laterallus spilonota''), version 1.0. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.galrai1.01 retrieved 28 November 2022]
The Galapagos crake is monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...
.[
]
Description
The Galapagos crake is about long and weighs about . The sexes are alike. Adults have a dark gray crown and medium gray head and underparts. Their flanks and thighs have sparse narrow whitish bars. Their interscapulars, scapulars, and upper back are chestnut brown and the lower back, rump, uppertail coverts
A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which, as the name implies, cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts
The ear coverts are sm ...
, and tail are dark brown. Their upper wing coverts also are brown, and may have fine white spots, and their flight feathers are light brown. Their iris is a distinctive red, and the bill, tarsi, and toes are dark brown. Juveniles have a mostly dark brown body with a lighter brown upper back; black lower back, rump, and tail; and slightly grayish face and throat. Their wings are an almost-black brown.[
]
Distribution and habitat
The Galapagos crake is found on the Galápagos islands of Pinta, Fernandina, Isabela, Santiago
Santiago (, ; ), also known as Santiago de Chile, is the capital and largest city of Chile as well as one of the largest cities in the Americas. It is the center of Chile's most densely populated region, the Santiago Metropolitan Region, whose ...
, Santa Cruz, San Cristóbal, and Floreana
Floreana Island (Spanish: ''Isla Floreana'') is an island of the Galápagos Islands. It was named after Juan José Flores, the first president of Ecuador, during whose administration the government of Ecuador took possession of the archipelago. ...
, though the populations on the last two islands might be extinct.[ It inhabits humid highlands on those islands in areas with dense fern, shrub, and ]forb
A forb or phorb is an herbaceous flowering plant that is not a graminoid (grass, sedge, or rush). The term is used in biology and in vegetation ecology, especially in relation to grasslands and understory. Typically these are dicots without woo ...
cover.[
]
Behavior
Movement
The Galapagos crake is a year-round resident. It can fly and swim, though it does not fly well nor for long distances. Its flight has been described as awkward and labored. It tends to run rather than fly to escape danger.
Feeding
The Galapagos crake forages during the day, moving along the ground in dense growth tossing leaves and investigating the leaf litter. Its primary prey is insects of many types and its diet includes other arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...
s, snails, and berries and seeds.[
]
Breeding
The Galapagos crake's breeding season has not been fully defined but appears to span from September to April. It is aggressively territorial; it stamps its feet and raises its tail as a threat and may run towards other rails that encroach on its territory. Pairs are monogamous during the breeding season but it is not known if the bond lasts year-round. The species makes its nest on the ground; it is a partially covered cup made of herbaceous plant matter with a side entrance. The clutch size is three to six eggs. The incubation period is 23 to 25 days and both parents incubate. Chicks take about 80 to 85 days from hatch to reach adulthood.[
]
Vocalization
The Galapagos crake gives at least five vocalizations, "cheeping, a ''chichichichiroo'' call, a ''chirr'' call, a chatter call, and a rattle call". They variously are used for members of a family to maintain contact, to advertise territory, and to intimidate predators.[
]
Status
The IUCN
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
originally assessed the Galapagos crake as Near Threatened but since 2000 has classified it as Vulnerable. It has a very limited range and its estimated population of between 3300 and 6700 mature individuals is believed to be decreasing. Destruction of habitat by cattle, goats, and pigs is a major cause of population decline; when they were removed from Santiago Island the crake population rebounded. Climate change and its associated severe weather events may affect the crake's habitat. Feral rats, cats, and dogs, and native short-eared owl
The short-eared owl (''Asio flammeus'') is a widespread grassland species in the family Strigidae. Owls belonging to genus ''Asio'' are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or ...
s (''Asio flammeus'') are potential threats as well.[
]
References
Further reading
* Taylor, B. (1998) ''Rails, a Guide to the Rails, Crakes, Gallinules and Coots of the World'', Yale University Press,
{{Taxonbar, from=Q1273247
Galapagos crake
The Galapagos crake (''Laterallus spilonota''), also called the Galapagos rail and Darwin's rail, is a Vulnerable species of rail in subfamily Rallinae of family Rallidae, the rails, gallinules, and coots. It is endemic to the Galápagos Islan ...
Endemic birds of the Galápagos Islands
Galapagos crake
The Galapagos crake (''Laterallus spilonota''), also called the Galapagos rail and Darwin's rail, is a Vulnerable species of rail in subfamily Rallinae of family Rallidae, the rails, gallinules, and coots. It is endemic to the Galápagos Islan ...
Galapagos crake
The Galapagos crake (''Laterallus spilonota''), also called the Galapagos rail and Darwin's rail, is a Vulnerable species of rail in subfamily Rallinae of family Rallidae, the rails, gallinules, and coots. It is endemic to the Galápagos Islan ...