Eastern Grass Owl (Tyto longimembris) [XC860763]
by id from \u6d59\u6c5f\u7701\u6d77\u76d0\u53bf\u79e6\u5c71\u6d77\u6ee8, China (nocturnal flight call)
Eastern Grass Owl (Tyto longimembris) [XC660216]
by Jerome Chie-Jen Ko from Limeburners Creek Nature Reserve, New South Wales, Australia (nocturnal flight call)
Nest
A shallow scrape or depression in the ground, under or in a tussock of grass.
Eggs (Guide)
3 - 8; dull white; ellipsoidal; about 4-0 - 45 x 30 - 33 mm. Incubation: about 31 - 42 days; by female. Eggs are laid on alternate nights.
Young
Semi-altricial, nidicolous. Fledge in about 56 days. Fed by both parents after 4 - 5 weeks.
Subspecies
African Grass-owl (Tyto capensis) and Grass Owl (Tyto longimembris) (Sibley and Monroe 1990, 1993), cross-regional species, are retained as separate species contra Christidis and Boles (1994) who include longimembris as a subspecies of African Grass-owl (Tyto capensis).
Forms superspecies with African Grass-owl (Tyto capensis), with which often considered conspecific. Variation within species poorly understood, owing to rarity of specimens from whole range. Several other forms previously separated racially (walleri, oustaleti, maculosa) now included in nominate longimembris, although Australian walleri perhaps warrants recognition due to plumage differences and sexual dimorphism. Guangxi Zhuang and Guangdong population (melli) merged with chinensis. Subspecies chinensis itself sometimes included in pithecops, but probably better retained as separate subspecies.
The following 6 subspecies are recognised:
longimembris (Jerdon, 1839) - India, southern Nepal, Bangladesh and Myanmar; Sulawesi, Tukangbesi Is (Kaledupa), Flores, Sumba and north, central and eastern Australia.
chinensis Hartert, 1929 - South-eastern China (south-eastern Yunnan to Jiangsu) and Vietnam.
pithecops (Swinhoe, 1866) - Taiwan.
amauronota (Cabanis, 1872) - Philippines.
baliem Ripley, 1964 - Western New Guinea (Baliem Valley, Snow Mts).
papuensis Hartert, 1929 - Eastern New Guinea (central and south-eastern ranges, Huon Peninsula).