Grey-backed thrush

Grey-backed thrush
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Turdidae
Genus: Turdus
Species:
T. hortulorum
Binomial name
Turdus hortulorum

The grey-backed thrush (Turdus hortulorum) is a species of bird in the family Turdidae. It breeds in northeastern China, the Russian Far East and North Korea, and winters mainly in southern China and northern Vietnam. The species inhabits temperate forests and wooded habitats and is migratory.

Description

The grey-backed thrush is a medium-sized passerine measuring approximately 20 to 23 cm (7.9 to 9.1 in) in length. It is sexually dimorphic. Males have slate-grey upperparts and breast, a whitish chin and belly, and rufous-orange flanks. Females have greyer or browner upperparts, with dark spotting on the breast and similar rufous coloration on the flanks.

The mean recorded body mass is 66.7 g (2.35 oz), with recorded individuals ranging from 61 to 69 g.

Distribution and habitat

The grey-backed thrush is monotypic. It breeds in southeastern Siberia, northeastern China and North Korea. In China, its breeding range is concentrated in the northeast, while wintering birds occur mainly south of the Yangtze River. It also winters in northern Vietnam.

During the breeding season, the species inhabits deciduous and mixed forests, often in hilly terrain. A study of 79 nests in Jilin Province, northeastern China, found that nest placement and surrounding vegetation influenced breeding success. In winter it also occurs in more open woodland, bamboo and scrub habitats.

Behaviour and ecology

The grey-backed thrush forages on the ground, including in leaf litter along forest paths. Its diet includes both invertebrates and fruit.

A study of breeding grey-backed thrushes in northeastern China monitored 79 nests during the 2008 breeding season. Of these, 29 were successful, while predation accounted for most nest failures. Another experimental study found that grey-backed thrushes rejected all 12 experimentally introduced foreign eggs, indicating a strong egg-recognition response.

Captive breeding observations have recorded a clutch of five eggs, with hatching occurring 14 days after the first egg was laid and fledging 12 days later.

Conservation

The grey-backed thrush is classified as Least Concern by the International Union for Conservation of Nature. Its population trend is currently considered unknown.

References

Egg, collection of Museum Wiesbaden
  1. 1 2 BirdLife International (2018). "Turdus hortulorum". IUCN Red List of Threatened Species. 2018 e.T22708753A132075192. doi:10.2305/IUCN.UK.2018-2.RLTS.T22708753A132075192.en. Retrieved 12 November 2021.
  2. 1 2 3 4 5 Carey, G. J.; Pang, C. C. (2023). "Grey-backed Thrush Turdus hortulorum". The Avifauna of Hong Kong. Hong Kong Bird Watching Society. Retrieved 5 October 2026.
  3. 1 2 3 4 Collar, Nigel; de Juana, Eduardo (2020). "Gray-backed Thrush (Turdus hortulorum)". Birds of the World. Cornell Lab of Ornithology. doi:10.2173/bow.gybthr1.01.
  4. ↑ Dunning, John B. (2008). CRC Handbook of Avian Body Masses (2nd ed.). CRC Press. p. 360. ISBN 978-1-4200-6444-5.
  5. 1 2 Zhou, Daqing; Zhou, Chunfa; Kong, Xiangkun; Deng, Wenhong (2011). "Nest-site selection and nesting success of grey-backed thrushes in northeast China". The Wilson Journal of Ornithology. 123 (3): 492–501. doi:10.1676/10-110.1.
  6. ↑ Corlett, Richard T. (1998). "Frugivory and seed dispersal by birds in Hong Kong shrubland". Forktail. 13.
  7. ↑ "High egg rejection rate in a Chinese population of grey-backed thrush (Turdus hortulorum)". Zoological Research. 2019. PMC 6591160. PMID 31011133.