There is some uncertainty about the number of subspecies on Réunion, with most authorities only accepting a single, the nominate (Z. b. borbonicus), while some also accept Z. b. alopekion, and Z. b. xerophilus. When only a single Réunion subspecies is accepted, alopekion and xerophilus are considered to represent morphs of the nominate.[citation needed]
Description
It has a length of 9.5 cm. Its plumage exhibits colour morphs which vary from gray to brown. The tail coverts are conspicuously white, unlike those of the Réunion olive white-eye. The rest of the body plumage is variable in hue, though invariably lighter than that of the previous species.[4] It is typically blue-grey with a brownish wash to the mantle, and distinctly rufous-brown flanks. It has chestnut-coloured eyes with a very indistinct eye-ring, as opposed to that of the Réunion olive white-eye. In both species the breast and flank feathers create a white "epaulette" effect.[4]
Biology
It inhabits woodlands, forests, and gardens. It is the only endemic bird from Réunion which has adapted to man-made conditions. Its diet consists of insects, fruits and nectar. It is also the pollinator for orchids like Angraecum striatum or the endemic Trochetia species. It moves often in small groups from six to twenty birds in search of food. They are very noisy. The breeding period is in the southern summer. The female lays two to four pale blue eggs in a cup-shaped nest which is padded with plant material.
Gallery
Brown morph at Col des Boeufs displaying white "epaulettes"
^del Hoyo, J.; Elliot, A. & Christie D. (editors). (2008). Handbook of the Birds of the World. Volume 13: Penduline-tits to Shrikes. Lynx Edicions. ISBN978-84-96553-45-3
^Gill F. and Donsker D. (eds), Family Zosteropidae, in IOC World Bird Names (ver 6.2), International Ornithologists’ Union, 2016. URL [1]
^ abSinclair, Ian; Langrand, Olivier (1998). Birds of the Indian Ocean Islands. Cape Town: Struik Publishers. pp. 150–151. ISBN1-86872-035-7.
Bibliography
France Staub: Birds of the Mascarenes and Saint Brandon. LABAMA HOUSE, Port Louis, Mauritius, 1976.
France Staub: Fauna of Mauritius and associated flora. Précigraph Limited, Port Louis, Mauritius, 1993.
Claire Micheneau, Jacques Fournel & Thierry Pailler: Bird Pollination in an Angraecoid Orchid on Reunion Island (Mascarene Archipelago, Indian Ocean). Annals of Botany 97: S. 965–974, 2006 doi:10.1093/aob/mcl056PDF fulltext[dead link]