The pink pigeon (''Nesoenas mayeri'') is a species of pigeon in the family

Columbidae Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...

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 ...

Mauritius Mauritius ( ; french: Maurice, link=no ; mfe, label=Mauritian Creole, Moris ), officially the Republic of Mauritius, is an island nation in the Indian Ocean about off the southeast coast of the African continent, east of Madagascar. It incl ...

. The pink pigeon nearly became extinct in the 1970s and the 1990s and is still very rare. It is the only

Mascarene The Mascarene Islands (, ) or Mascarenes or Mascarenhas Archipelago is a group of islands in the Indian Ocean east of Madagascar consisting of the islands belonging to the Republic of Mauritius as well as the French department of Réunion. Thei ...

pigeon that has not become extinct. It was on the brink of extinction in 1991 when only 10 individuals remained, but its numbers have increased due to the efforts of the

Durrell Wildlife Conservation Trust Durrell Wildlife Conservation Trust is a conservation organization with a mission to save species from extinction. Gerald Durrell founded the Jersey Wildlife Preservation Trust as a charitable institution in 1963 with the dodo as its symbol. T ...

since 1977. While the population remains at below 500 birds as of 2011, 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 ...

downlisted the species from Critically endangered to

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

on 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 the world's most comprehensive inventory of the global conservation status of biol ...

in 2000, and then downlisted it again to Vulnerable in 2018.

Taxonomy and evolution

Initially classified as a true pigeon, the pink pigeon was reclassified in a monotypic genus by

Tommaso Salvadori Count Adelardo Tommaso Salvadori Paleotti (30 September 1835 – 9 October 1923) was an Italian zoologist and ornithologist. Biography Salvadori was born in Porto San Giorgio, son of Count Luigi Salvadori and Ethelyn Welby, who was English. His ...

. Recent DNA analyses suggest its nearest relative is the geographically close

Malagasy turtle dove The Malagasy turtle dove (''Nesoenas picturatus'') is a bird species in the pigeon and dove family, Columbidae. It is found in Mauritian-Indian Ocean Territory, the Comoros, Madagascar, Mauritius, Mayotte, Réunion, and the Seychelles. Taxono ...

(''Streptopelia picturatus''), and it has thus been suggested that it be placed in the genus ''

Streptopelia ''Streptopelia'' is a genus of birds in the pigeon and dove family Columbidae. These are mainly slim, small to medium-sized species. The upperparts tend to be pale brown and the underparts are often a shade of pink. Many have a characteristic bla ...

'', which mostly contains turtle doves. However, the two species form a distinct group that cannot unequivocally be assigned to either ''Streptopelia'' or ''Columba'', and placing both species in ''Nesoenas'' may best reflect the fact that they seem to belong to a distinct evolutionary lineage. This classification has been followed here. The extinct

Réunion pink pigeon The Réunion pink pigeon (''Nesoenas mayeri duboisi'', but see below) is an extinct subspecies of pigeon that formerly lived on the Mascarene island of Réunion. It is known from the description of a rusty-red pigeon given by Sieur Dubois, Duboi ...

is now considered a subspecies.

Description

An adult pink pigeon is about from beak to tail and 350 grams in weight. Pink pigeons have pale pinkish-grey plumage on their head, shoulders and underside, along with pink feet. The beak is a dark pink color with a white tip. They have dark brown wings, and a broad, rust-colored tail. Their eyes are dark brown surrounded by an eye-ring of red skin. Newly hatched pigeons have sparse, downy-white feathers and closed eyes. The voice of the pink pigeon consists of a flight call that is a short, hardened ''"hoo hoo"''. The territorial call of the male pink pigeon is a series of coos.

Distribution and habitat

The species is

to the

island of

, a small island to the east of Madagascar in the Indian Ocean, and the tiny predator-free island of Isle aux Aigrettes off its eastern coast. A subspecies, the

, became extinct on the neighbouring

Reunion Island Reunion may refer to: * Class reunion * Family reunion Reunion, Réunion, Re-union, Reunions or The Reunion may also refer to: Places * Réunion, a French overseas department and island in the Indian Ocean * Reunion, Commerce City, Colorado, US ...

around 1700. As of 2016, there are five locations places where wild populations of the pink pigeon can be found. Four of these locations belong to Black River Gorges National Park and the fifth to Isle aux Aigrettes. All are monitored by the Mauritian Wildlife Foundation. The species is not migratory. The species prefers upland evergreen forests, but is equally at home in coastal forests as long as the vegetation is native and not dominated by introduced species such as Chinese Guava (''Psidium cattleianum'') or the

privet A privet is a flowering plant in the genus ''Ligustrum''. The genus contains about 50 species of erect, deciduous or evergreen shrubs, sometimes forming small or medium-sized trees, native species, native to Europe, north Africa, Asia, many in ...

(''

Ligustrum robustum ''Ligustrum robustum'' grows as a shrub or small tree up to tall though old specimens of more than a hundred years have been observed with a height of . The fruit of the shrub is an ellipsoid berry, bluish-purple when fully ripe, × . ...

''). Destruction of such primal forests has been a major reason for its decline.

Behavior and ecology

The breeding season of the pink pigeon begins in August–September, although birds may breed all year round. The male courts the female with a "step and bow" display. Mating is generally monogamous, with the pair making a flimsy platform nest and defending a small area around it (even though the pigeons initially had no natural predators, one mating pair must defend their territory from other mating pairs). Pink pigeons generally mate for life. The female usually lays two white eggs, and incubation duration is two weeks. The male incubates during the day, and the female during night and early day. They may breed often, laying five to 10 eggs in a season; breeding only pauses in the wild whilst in molt, which may be full or a partial-body/head molt. There are more males than females in a population due to greater life expectancy of the male (about five years more) and in the wild a higher chance of the female being predated. One reason for the difference in life span is that producing eggs is extremely metabolically taxing, and since female birds are nearly constantly producing eggs (even when they are not fertilized, just like domestic chickens do) this can end up totaling to a large metabolic tax on the female's survival. In captivity, males remain fertile to an age of 17–18 years, females to an age of 10–11 years.

Life history timeline

* 1 – 7 days: Chicks eyes closed, fed entirely on

crop milk Crop milk is a secretion from the lining of the crop of parent birds that is regurgitated to young birds. It is found among all pigeons and doves where it is referred to as pigeon milk. An analog to crop milk is also secreted from the esopha ...

. * 7 – 10 days: Chicks undergo a dietary transformation to solid food. * 2 – 4 weeks: Chicks fledge, but remain parent-fed. * 4 - 6/7 weeks: Chicks remain in the nest. After this, the chicks leave the nest.

Diet

Feeding in the wild

The pink pigeon is herbivorous, feeding on both exotic and native plants - consuming buds, flowers, leaves, shoots, fruits and seeds. These birds exhibit ground-feeding behaviors, moving and turning over leaf litter in order to find food and grit (for use as

gizzard stones A gastrolith, also called a stomach stone or gizzard stone, is a rock held inside a gastrointestinal tract. Gastroliths in some species are retained in the muscular gizzard and used to grind food in animals lacking suitable grinding teeth. In oth ...

Supplemental feeding

Because the pink pigeon's natural habitat has become degraded, natural food sources have in the past been deemed insufficient to sustain the wild population or allow successful breeding and chick-rearing. The MWF and other organizations are providing supplemental feeding stations that offer diet items like whole wheat. To prevent other bird species from plundering this feed, special feeding platforms have been designed that allow access primarily to pink pigeons only.

Conservation

The pink pigeon is currently classified as Vulnerable by the

, having been downlisted from

in 2018 and Critically Endangered in 2000. Due to

habitat destruction 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 introduced predators, the population had dropped to 10 in 1991. The captive breeding and reintroduction program initiated and supported by the Durrell Wildlife Conservation Trust and largely carried out by the Mauritian Wildlife Foundation has resulted in a population of about 400 in the wild in 2018, as well as a healthy captive population as backup. Several foundations and organizations have contributed to conservation efforts. In addition to direct conservation efforts such as captive breeding, genetic research, and supplementary feeding efforts, more general research on the species may aid in the formation of more applicable conservation actions. Since October 2021, ''N. mayeri'' has been classified as Critically Depleted by the

Threats

Habitat degradation, introduced predators, and wildlife disease are the major ongoing threats to the pink pigeon's survival. Only 2% of the native forest remains in Mauritius, with the majority of these remaining forests on upland slopes around the Black River Gorge National Park. Common predators include the

crab-eating macaque The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories, is a cercopithecine primate native to Southeast Asia. A species of macaque, the crab-eating macaqu ...

(''Macaca fascicularis''), the

small Asian mongoose Small Asian mongoose is a common name applied to two mammals which were formerly considered to be a single species: * Javan mongoose *Small Indian mongoose The small Indian mongoose (''Urva auropunctata'') is a mongoose species native to Iraq an ...

(''Urva auropunctata''), rats, and

feral cat A feral cat or a stray cat is an unowned domestic cat (''Felis catus'') that lives outdoors and avoids human contact: it does not allow itself to be handled or touched, and usually remains hidden from humans. Feral cats may breed over dozens ...

s. Invasive plant species, such as the Chinese guava and

, dominate native forest plants, preventing their growth. Without these native plant species, the pink pigeon finds it hard to locate sound nesting locations or food sources.

Extreme weather Extreme weather or extreme climate events includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Often, extreme events are based on a locat ...

events such as cyclones may also further the degradation of habitat. The feeding stations that provide supplementary feed may accelerate the spread of disease between individuals, who congregate at greater than normal numbers at stations. This may apply to trichomonosis, originally brought to Mauritius by introduced pigeons. Feeding stations therefore have to be closely managed to reduce the associated risks. An ongoing concern faced by the pink pigeon, as by many endangered species that exist in small remnant populations, is

inbreeding depression Inbreeding depression is the reduced biological fitness which has the potential to result from inbreeding (the breeding of related individuals). Biological fitness refers to an organism's ability to survive and perpetuate its genetic material. In ...

In culture

The book ''Golden Bats and Pink Pigeons'' by

Gerald Durrell Gerald Malcolm Durrell, (7 January 1925 – 30 January 1995) was a British naturalist, writer, zookeeper, conservationist, and television presenter. He founded the Durrell Wildlife Conservation Trust and the Jersey Zoo on the Channel Island o ...

describes the conservation efforts. Mauritius has published a series of

postage stamp A postage stamp is a small piece of paper issued by a post office, postal administration, or other authorized vendors to customers who pay postage (the cost involved in moving, insuring, or registering mail), who then affix the stamp to the fa ...

s depicting the pink pigeon.