Détails de cette espèce dans New Zealand
Statut d'envahissement: Envahissant
Source: P. R. Wilson Pers. Comm.
Notes sur l'espèce pour cette localité:
The common myna was introduced throughout New Zealand in the 1870s by locals and Acclimatisation Societies (Bull et al. 1985). Birds subsequently established in most of the North Island, with high densities present in the urban and suburban areas. Common mynas continue to flourish in the northern and central North Island, and are usually more abundant than most native birds in gardens and parks (LCR 2008). The common myna is present in northern New Zealand as far south as Wanganui which is the southernmost point of its global range (40º S). Mynas are locally abundant in the northern North Island in farmland, orchards and suburban gardens, and have colonised some offshore islands such as Poor Knights, Waiheke, Kawau and Great Barrier.
Although most abundant in modified environments, the myna is sympatric with native and other introduced birds throughout most habitats in northern New Zealand, including native foresTindall Ralph & Clout 2007). Local populations of the common myna appear to be expanding; indices of myna abundance increased in six forests over a 14 year period between 1979 and 1993.
Mynas persisted in the South Island (Nelson, Christchurch and Dunedin) until about 1890; they fared better in the North Island and by the 1930s they were split into two populations: one in the east from Waipukurau to East Cape, and the other in the west from Wanganui to the Waikato. From about 1940 they spread quickly to colonise the Volcanic Plateau and reached Auckland by about 1947, Tauranga and Rotorua about 1950, the Bay of Islands 1960 and Kaitaia 1965. At the same time they were disappearing from the southern North Island. They were once numerous in Wellington, Masterton and Palmerston North, but apart from a small popluation based on the Masterton Refuse Tip, and other odd birds, the southern limit is a line from Wanganui to Waipukurau and this is still shifting slowly northwards (P. R. Wilson Pers. Comm.). In New Zealand, they seemed to find it too cold around Nelson except for some individuals based in piggery sheds where it is warm enough and where there are sufficient sources of food for them to thrive (P. R. Wilson Pers. Comm.).
Notes sur la gestion de l'espèce dans cette localité:
Rat snap-traps have been used successfully to reduce common myna numbers at one locality in northern New Zealand (R. Pierce Pers. Obs.,). This involved baiting of standard rat traps with bread, including bread scattered around a roof top site. Mynas were arriving erratically (usually 1-2 per week) at the site, with typically one of these birds being trapped and the others leaving the area, presumably because of the obvious threat posed by the traps. Some other exotic birds were also killed.
Autre: Common myna nests have been found in nest-boxes established for saddlebacks (Philesturnus carunculatus) on the Hen and Chickens island group, although no displacement has been observed (R. Pierce Pers. Obs., 2005). Breeding success of the common starling (Sturnus vulgaris) may be reduced to very low levels because of destruction of nests by mynas (Wilson 1979).
Compétition: Hole-nesting species displaced by common myna from nests in New Zealand include the sacred kingfisher (Todiramphus sanctus) (several records) and the introduced eastern rosella, some of which have involved loss of eggs or chicks (Moon 1991, CSN 1994).
Prédation: Mynas are omnivorous and anecdotal observations suggest that they frequently kill reptiles and birds' eggs and young. Most recorded bird deaths are from New Zealand and they include eggs and nestlings of the New Zealand wood pigeon (Hemiphaga novaeseelandiae), sacred kingfisher (Todiramphus sanctus), tui (Prosthemadera novaeseelandiae), grey warbler (Gerygone igata) and fantail (Rhipidura fuliginosa) (CSN 1972: McKenzie 1979, Heather and Robertson 2000).
Further study is needed, in different situations, to determine whether mynas are a significant factor in species recovery. For example, Armstrong and colleagues (2000) suspected that mynas were the key avian predator species responsible for significant nest failure of North Island robins (Petroica australis longipes) in secondary forest on Tiritiri Matangi Island, New Zealand. It is also suspected that mynas affect the nesting success of red-crowned kakariki (Cyanoramphus noveseelandiae) on northern New Zealand islands and at sites on the adjacent mainland where control of mammalian predators is underway.
Dernière mise à jour: 27/11/2009 2:29:28 p.m.