Chatham Island Pigeon Hemiphaga chathamensis Scientific name definitions

51 cm; 680–750 g. A large  , plump green and white pigeon, with an ash-grey wash all over. Head , throat  , upper breast and upperparts blackish grey; clearly demarcated white lower breast  , underparts and legs; red bill  with pale yellow tip, red brown eyes, orange-pink orbital ring, and dull red legs and feet. Juvenile differs from adult in duller, darker upperparts and buff undertail-coverts. Similar to <em>H. novaeseelandiae</em> but larger, with much heavier, longer bill; dark plumage duller overall; rump grey; breast darker with more purple iridescence; undertail-coverts dark; tail mainly blue and purple; primary-coverts much greyer; wing-linings mostly white. See also Taxonomy comments.

Usually considered conspecific with H. novaeseelandiae, but differs in its grey vs blue-green rump and primary wing-coverts (3); matt blackish-grey vs glossy dark green crown, throat, breast and neck-sides (3); reduced dull maroon carpal area (2); dark green vs whitish undertail-coverts (ns[2]); darker tail (ns[1]); much stouter bill (not measured, but estimated at 2); also modest genetic divergence (1 Goldberg, J., Trewick, S.A. and Powlesland, R.G. (2010). Population structure and biogeography of Hemiphaga pigeons (Aves: Columbidae) on islands in the New Zealand region. J. Biogeogr. 38(2): 285–298. Close ). Monotypic.

Chatham Is on Chatham, Pitt and maybe still Rangetira (2 Shirihai, H. (2007). A Complete Guide to Antarctic Wildlife. The Birds and Marine Mammals of the Antarctic Continent and the Southern Ocean. 2nd edition. A&C Black, London. Close ); extinct on Mangere (3 Gill, B. J., B. D. Bell, G. K. Chambers, D. G. Medway, R. L. Palma, R. P. Scofield, A. J. D. Tennyson, and T. H. Worthy (2010). Checklist of the Birds of New Zealand, Norfolk and Macquarie Islands, and the Ross Dependency, Antarctica. 4th edition. Ornithological Society of New Zealand & Te Papa Press, Wellington, New Zealand. Close ).

Frequents native forest, including extensive tracts and small patches; stunted scrub- and bracken-covered areas; and pasture adjacent to forest or shelterbelts. Most of population occurs in S Chatham I, with a few in forest patches near S & W shores of Te Whanga Lagoon, and intermittently in forest patches elsewhere on the island.

Diet mainly leaf buds, leaves, flower buds, flowers and fruit of a variety of species but fruit, which is richer in lipids and available carbohydrates than leaves, seems to be preferred food type. Pairs feeding young take mainly ripe fruit but also include flower buds, flowers and leaves in their diet. Abundance of hoho (Pseudopanax chathamicus) fruit (Araliaceae), which ripens in winter–spring, has marked influence on timing and duration of breeding. Fruit of Matipo (Myrsine chathamica, Myrsinaceae) also important in autumn (March–May). When little or no fruit is available, feeds mainly on leaves, including the relatively tough leaves of hoho (4 Powlesland, R.G., Dilks, P.J., Flux, I.A., Grant, A.D. and Tisdall, C.J. (1997). Impact of food abundance, diet, and food quality on the breeding of the fruit pigeon, Parea Hemiphaga novaeseelandiae chathamensis, on Chatham Island, New Zealand. Ibis. 139(2): 353-365. Close ). Relatively robust beak (compared to that of H. novaeseelandiae) may be an adaptation to consuming such tough food. Other important foliage sources include Trifolium (Papilionaceae), Stellaria (Caryophyllaceae) and Hydrocotyle (Umbelliferae). Birds often feed on ground , as well as in trees, which makes them vulnerable to predation. Consumption of Brassica crops reported.

Apparently similar to H. novaeseelandiae  .

Has been found breeding in all months, but predominantly nests during winter and spring (Jun–Nov). In seasons when fruit is readily available, many pairs rear two chicks (i.e. two separate breeding attempts), often involving overlapping nesting events. Breeding pairs territorial. Male performs display flight to deter intruders, comprising a steep climb followed by a slow glide back to a high perch with wings and tail spread. Heavy fruiting of matipo (Myrsine chathamica) and hoho (Pseudopanax chathamicus) promotes early nesting and prolongs the breeding season for six months, including into winter (4 Powlesland, R.G., Dilks, P.J., Flux, I.A., Grant, A.D. and Tisdall, C.J. (1997). Impact of food abundance, diet, and food quality on the breeding of the fruit pigeon, Parea Hemiphaga novaeseelandiae chathamensis, on Chatham Island, New Zealand. Ibis. 139(2): 353-365. Close ). Nest  is a platform of dead twigs, and a single white egg  is laid, incubated 26–28 days. No further information.

VULNERABLE. Listed as Critical by New Zealand authorities (5 Miskelly, C. M., J. E. Dowding, G. P. Elliott, R. A. Hitchmough, R. G. Powlesland, H. A. Robertson, P. M. Sagar, R. P. Scofield, and G. A. Taylor, (2008). Conservation status of New Zealand birds, 2008. Notornis 55(3):117–135. Close ). Formerly occurred on islands of Mangere and Pitt, and there is a reintroduced population on South East I. Global population had declined to an estimated 45 birds in 1989 or even c. 30 in 1990, but is now increasing owing to successful conservation action, involving control of predators (especially feral cats, rats and possums) and the designation of protected areas, notably Tuku Nature Reserve (6 Flux, I.A., Powlesland, R.G., Dilks, P.J. and Grant, A.D. (2001). Breeding, survival, and recruitment of Chatham Island pigeon (Hemiphaga chathamensis). Notornis. 48(4): 197–206. Close ). A total population of more than 600 individuals was estimated in 2009 (7 Dilks, P.J., Powlesland, R.G., Adams, L.K. and Flux, I.A. (2010). Changes in abundance of parea (Chatham Islands pigeon, Hemiphaga chathamensis), 1994-299999. Notornis. 57(3): 156–161. Close ). Much of Chatham’s original forest cover has been lost, and the species is now restricted to Tuku Nature Reserve (1238 ha) and adjacent covenants. Because it spends considerable time on the ground grazing on leaves and fruit, the species is an easy target for feral cats. Cats, possums, rats, feral pigs and Wekas (Gallirallus australis) can easily access nests, which can often be in low vegetation or occasionally on the ground.