These colours were thought similar to those of the Dutch flag, a resemblance reflected in its French common name, Pigeon Hollandais.

The last specimen recorded was shot in Savanne in 1826 and given to Julien Desjardins, founder of the Mauritius Natural History Museum in Port Louis, where it is still located, though in poor condition.

[15][8] Subfossil remains of the Mauritius blue pigeon were collected in the Mare aux Songes swamp by Théodore Sauzier in 1889.

[8] Alectroenas blue pigeons are closely interrelated and occur widely throughout islands in the western Indian Ocean.

[18] Their closest genetic relative is the cloven-feathered dove of New Caledonia (Drepanoptila holosericea), from which they separated 8–9 million years ago.

[20] A blue pigeon recorded as being from Mauritius was brought to the Netherlands around 1790, where it survived in the menagerie of William V, Prince of Orange for three months before dying of oedema.

The only known life drawings thought to show the species depict this individual; they were drawn by the Dutch artist Gijsbertus Haasbroek and first published by Piet Tuijn in 1969 (along with the Gelderland sketches).

Both sexes of the Seychelles blue pigeon also have red foreheads, and the English palaeontologist Julian P. Hume suggested that the image depicts a male, which was described as "infinitely more handsome" than the female by Cossigny in the mid-18th century.

[21] In 2020, the Dutch researcher and artist Ria Winters noted that the depicted bird was in fact a Seychelles blue pigeon.

A patch of bright red, naked skin surrounded the eyes, and extended across the cheeks to the beak, which was greenish with a dark tip.

[2] It was the largest and most robust member of its genus, and the hackles were longer and covered a larger area than in other blue pigeons.

[24] This feature was unknown from contemporary accounts, until the 1660s report of Johannes Pretorius about his stay on Mauritius was published in 2015, where he mentioned the bird's "warty face".

[21] The bird probably lived in pairs or small groups in humid, mountainous evergreen forests, like their extant relatives.

By 1812, the French naturalist Jacques Gérard Milbert stated that solitary individuals were found in river valleys.

[26] Many other endemic species of Mauritius became extinct after the arrival of humans, so the ecosystem of the island is severely damaged and hard to reconstruct.

The small Mauritian flying fox and the snail Tropidophora carinata lived on Mauritius and Réunion but became extinct in both islands.

[23] Cossigny dissected a specimen in the mid-18th century and later sent it and its stomach contents to the French scientist René Antoine Ferchault de Réaumur with a letter describing his findings.

[30] The gizzard and crop contained four "nuts", which Cossigny was told were the seeds of either Calophyllum tacamahaca or Labourdonnaisia calophylloides.

The Comoro and Seychelles blue pigeons also feed on C. tacamahaca, and the strong gizzard of the former helps in the digestion of the seeds.

[24] In 1812 Jacques Gérard Milbert provided the only description of the behaviour of the bird in the wild: The second is the pigeon with a mane; the inhabitants of the Ile de France [Mauritius] call it pigeon hollandais; the head, neck and chest are adorned with long pointed white feathers which it can raise at will; the rest of the body, and the wings, are a fine deep violet; the end of the tail is a purplish red.

[26]The claim that the bird fed on river molluscs was criticised by the French zoologists Alphonse Milne-Edwards and Emile Oustalet in 1893, with the later agreement of the American ornithologist James Greenway in 1967, as blue pigeons are principally arboreal.

[32] Cossigny noted that the bird had become rare by 1755, but were common 23 years before, and attributed the decline to deforestation and hunting by escaped slaves.

[33] The last confirmed specimen was shot in the Savanne district in 1826, but the 1832 report by Desjardins suggests that some could still be found in remote forests in the centre of the island.

[33] The second was a woman who had last seen a bird around this time, and recalled hunts of it in approximately 1815, in a swampy area near Black River Gorges, south western Mauritius: When she was a girl and used to go into the forest with her father de Chazal, she has seen quantities of Pigeon Hollandais and Merles [Hypsipetes olivaceus], both species were so tame they might be knocked down with sticks, & her father used to kill more that way than by shooting them, as she was a nervous child.

Her father always warned her before he fired, but she would entreat him to knock the bird down with his stick & not to shoot it – she said the last Pigeon Hollandais she saw was about 27 years ago just after she married poor old Moon, it was brought out of the forest by a marron.