Stephen's lorikeet (''Vini stepheni''), also known as the Henderson lorikeet or the Henderson Island Lorikeet, is a species of

parrot Parrots, also known as psittacines (), are birds of the roughly 398 species in 92 genera comprising the order Psittaciformes (), found mostly in tropical and subtropical regions. The order is subdivided into three superfamilies: the Psittaco ...

in the family

Psittaculidae Psittaculidae is a family containing Old World parrots. It consists of five subfamilies: Agapornithinae, Loriinae, Platycercinae Platycercinae is a subfamily of birds belonging to the family Psittaculidae that inhabit Oceania. It consists of ...

. 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 els ...

to Henderson Island in the

Pitcairn Islands The Pitcairn Islands (; Pitkern: '), officially the Pitcairn, Henderson, Ducie and Oeno Islands, is a group of four volcanic islands in the southern Pacific Ocean that form the sole British Overseas Territory in the Pacific Ocean. The four i ...

of the South Pacific. Its natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

subtropical or tropical moist lowland forest Tropical and subtropical moist broadleaf forests (TSMF), also known as tropical moist forest, is a subtropical and tropical forest habitat type defined by the World Wide Fund for Nature. Description TSMF is generally found in large, disco ...

. It is threatened by

habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

and the accidental introduction of predators to the island.

Description

The lorikeets are in length and weigh . Adults are green on the upper side, with a green

occiput The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cer ...

and crown. The green color turns into a yellow-green at the base and tail. They have a green underwings, with a green band across the chest that varies in appearance. Their breast is red in color, and turns purple towards their abdomen and thighs. They have a deep orange

beak The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for eating, preening, manipulating objects, killing prey, fighting, probing for fo ...

with yellow or orange eyes. Juvenile Stephen's lorikeets have green underparts with purple or red marks on their throats and abdomens. Their tail tends to be a dark green. They have brown beaks and eyes. The calls emitted while feeding are soft and twittering. The call made while in flight are louder.

Behavior and ecology

The lorikeets are hard to spot in dense foliage. They are generally found in small groups or

flocks Flocking is the behaviour exhibited when a group of birds, called a flock, are foraging or in flight. Computer simulations and mathematical models that have been developed to emulate the flocking behaviours of birds can also generally be applie ...

. They are known to travel between the inland foliage and coastal palms to feed on coconuts.

Diet

The diet of the birds is composed of nectar,

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametop ...

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in partic ...

s, and

butterfly Butterflies are insects in the macrolepidopteran clade Rhopalocera from the order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The group comprises ...

and

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of ...

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. Th ...

e. The majority of nectar eaten by the lorikeets comes from the flowers of '' Scaevola sericea'' and ''

Timonius polygamus ''Timonius'' is a genus of plants in the family Rubiaceae. It is the second most specious genus in the family in Papua New Guinea, containing about 80 species known to science,Bryan, J.E., Shearman, P.L. (Eds.). 2015. The State of the Forests of ...

''.

Reproduction

Their breeding season is thought to be around April or the start of May.

Threats

The lorikeets are assessed as

vulnerable Vulnerable may refer to: General * Vulnerability * Vulnerability (computing) * Vulnerable adult * Vulnerable species Music Albums * ''Vulnerable'' (Marvin Gaye album), 1997 * ''Vulnerable'' (Tricky album), 2003 * ''Vulnerable'' (The Used album) ...

by the IUCN. They are thought to have a stable population of 720-1820 individuals. Due to their extremely limited range, the main threat to the survival of the lorikeets is the accidental introduction of predators to Henderson Island and habitat loss due to deforestation or natural disasters. They, however, seem to have adjusted to the introduction of at least one invasive predator, the

Polynesian rat The Polynesian rat, Pacific rat or little rat (''Rattus exulans''), known to the Māori as ''kiore'', is the third most widespread species of rat in the world behind the brown rat and black rat. The Polynesian rat originated in Southeast Asia, ...

. There has been an unsuccessful attempt to eradicate invasive rodents from Henderson Island.

Distribution and habitat

The lorikeet is endemic to Henderson Island in the Pitcairn Islands. It inhabits coconut palms as well as the dense forest on the interior of the island.

References

{{Taxonbar, from=Q1265361 Stephen's lorikeet Birds of Henderson Island Stephen's lorikeet Stephen's lorikeet Taxonomy articles created by Polbot