The Masafuera rayadito (''Aphrastura masafuerae'') is 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 of

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

in the Furnariinae subfamily of the ovenbird

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Furnariidae. It 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 ...

Alejandro Selkirk Island Alejandro Selkirk Island (), previously known as Más Afuera (Farther Out (to Sea)) and renamed after the marooned sailor Alexander Selkirk, is the largest and most westerly island in the Juan Fernández Archipelago of the Valparaíso Region of ...

(''Isla Más Afuera'', Outermost Island) in the

Juan Fernández Islands The Juan Fernández Islands () are a sparsely inhabited series of islands in the South Pacific Ocean, reliant on tourism and fishing. Situated off the coast of Chile, they are composed of three main volcanic islands: Robinson Crusoe Island, R ...

of Chile.Clements, J. F., T. S. Schulenberg, M. J. Iliff, T. A. Fredericks, J. A. Gerbracht, D. Lepage, S. M. Billerman, B. L. Sullivan, and C. L. Wood. 2022. The eBird/Clements checklist of birds of the world: v2022. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ retrieved November 10, 2022

Taxonomy and systematics

The Masafuera rayadito 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 "unisp ...

. It shares genus ''Aphrastura'' with the

thorn-tailed rayadito The thorn-tailed rayadito (''Aphrastura spinicauda'') is a species of bird in the family Furnariidae. It is found in temperate forests and subtropical dry shrubland south of 30th parallel south, 30°S. Some sources suggest it may formerly have oc ...

(''M. spinicauda'') of the South American mainland. They are thought to have diverged in the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

Description

The Masafuera rayadito is long. The sexes have the same plumage. Adults have a poorly defined buff-brown

supercilium The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head.Dunn and Alderfer (2006), p. 10 Also k ...

on a dusky face. Their forehead is whitish with narrow rufous streaks and their crown is dark dusky brown. Their back is dull brown and their rump rufous-brown. Their wing coverts are blackish with tawny tips and their flight feathers are blackish with dull rufous bases. Their tail is mostly rufous with blackish bases on all but the central pair of feathers; the ends of the feathers lack barbs, giving a spiny appearance. Their throat is whitish, their breast and belly dull buffy gray-brown with a rufescent tinge, and their flanks and undertail

coverts 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 ...

rufescent. Their iris is brown, their

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

horn-brown or yellowish white with a horn tinge, their

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

yellowish horn, and their legs and feet horn-gray.Remsen, Jr., J. V., E. de Juana, and C. J. Sharpe (2020). Masafuera Rayadito (''Aphrastura masafuerae''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.masray1.01 retrieved September 10, 2023

Distribution and habitat

The Masafuera rayadito is found only on Alejandro Selkirk Island in the Juan Fernández Archipelago, about off the coast of Chile. It inhabits thick undergrowth in semi-humid to humid montane scrub and also wooded areas with much ''

Dicksonia ''Dicksonia'' is a genus of tree ferns in the order Cyatheales. It is regarded as related to '' Cyathea'', but is considered to retain more primitive traits, dating back at least to the Jurassic and Cretaceous periods. The fossil record includes ...

externa''

tree fern Tree ferns are arborescent (tree-like) ferns that grow with a trunk (botany), trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae ( ...

. It often occurs along streams, and often in stands of the canelo tree ''

Drimys confertifolia ''Drimys confertifolia'' is a species of flowering plant in family Winteraceae. It is native to Juan Fernández Islands off the western coast of South America. Description ''Drimys confertifolia'' is an evergreen tree or large shrub, growing up ...

''. In elevation it usually occurs between but occasionally goes as low as in the austral winter.

Behavior

Movement

The Masafuera rayadito is mostly resident but makes some downslope movement in winter.

Feeding

The Masafuera rayadito's diet is not well known, but is probably mostly

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

s. It almost always forages in pairs, usually in the understorey but sometimes in leaf litter on the ground. It feeds often on ferns, sometimes hanging upside down as it gleans from fronds. It also hunts in moss and lichens on the canelo tree.

Breeding

The Masafuear rayadito's breeding season includes at least December and January. It makes a nest of plant fibers in a natural cavity on a cliff face, and also in nest boxes provided by humans. The clutch size, incubation period, and time to fledging are not known. Both parents provision nestlings.Hahn, I., Römer, U. and Schlatter, R. (2004). Nest sites and breeding ecology of the Másafuera Rayadito (''Aphrastura masafuerae'') on Alejandro Selkirk Island, Chile. Journal of Ornithology. 145(2): 93–97

Vocalization

As of September 2023, neither

xeno-canto xeno-canto is a citizen science project and repository in which volunteers record, upload and annotate recordings of bird calls and sounds of orthoptera and bats. Since it began in 2005, it has collected over 575,000 sound recordings from more th ...

nor the

Cornell Lab of Ornithology The Cornell Lab of Ornithology is a member-supported unit of Cornell University in Ithaca, New York, which studies birds and other wildlife. It is housed in the Imogene Powers Johnson Center for Birds and Biodiversity in Sapsucker Woods Sanctuar ...

Macaulay Library The Macaulay Library is the world's largest archive of animal media. It includes more than 71 million photographs, 2.6 million audio recordings, and over three hundred thousand videos covering 96 percent of the world's bird species. There are an ev ...

had any recordings of Masafuera rayadito vocalizations. Its call is described as "a low churring 'trrrt' c. 1·2 seconds long, singly or repeated".

Status

The

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

originally assessed the Masafuerea rayadito in 1988 as Threatened, then in 1994 as Vulnerable, but since 2005 as Critically Endangered. It has an extremely small range on one small island and very strict habitat requirements. Surveys of the species in the 1980s found about 500 birds but by 2002 only 140 were documented. As of 2018 its population is estimated at between 50 and 250 mature individuals and is believed to be stable. "Introduced mammalian predators are thought to have a significant impact on the population, with rats (''Rattus'' spp.) and possibly mice (''Mus musculus'') impacting on brood survival, and feral cats impacting on juvenile and adult survival." In addition, "a large proportion of natural vegetation on the island has been degraded and fragmented by goat-trampling, fire and timber-cutting".

References

External links

BirdLife Species Factsheet.
{{Taxonbar, from=Q281040 Aphrastura Alejandro Selkirk Island Endemic birds of the Juan Fernández Islands Critically endangered animals Critically endangered biota of South America Birds described in 1866 Taxa named by Christian Ludwig Landbeck