Data Zone
Justification of Red List category
This species is listed as Vulnerable owing to a moderately rapid population reduction, which is thought to be the result of prey depletion owing to agricultural intensification and the consequent over-use of pesticides and rodenticides. Even though the species occurs localised over a large range, no localities are separated by geographic barriers, and a low level of migration between localities indicate that all individuals belong to the same subpopulation.
Population justification
The global population size was previously considered likely to exceed 10,000 mature individuals based on an extrapolation from a high density observed in Hong Kong (S. Chan in litt. 2007). However, it has become evident that the species is highly localised throughout the very large range, and this extrapolation from the density encountered in Hong Kong was inappropriate (P. Leader in litt. 2016, Leader et al. 2016). Recent efforts to improve the accuracy of the global population estimate have been conducted through a combination of an exhaustive compilation of historical and recent records and targeted field surveys at different locations within the range (Leader et al. 2016). This has resulted in a far lower estimate of the total population size of around 2,000 individuals (Leader et al. 2016). No attempt was made to account for the potential presence of additional, unsampled locations holding numbers of the species during the assessment, and there are reports of this species at locations not included in Leader et al.'s (2016) population estimate (S. Chan in litt. 2017, H. Huang in litt. 2018). Therefore, this estimate should be taken as the lower bound of a population estimate rather than a mid-point. The exercise did unearth a significant concentration of the species in eastern central China. Centred on the Dabie Shan mountain range in Henan, Hubei and Anhui provinces, an estimated 400-500 individuals were observed in the area over the course of a week in December 2014 (Leader et al. 2016). This indicates that additional localities with notable numbers may well be found. However, the presented estimate does represent a careful assessment of observations of the species, and it is unlikely that additional localities would increase the estimate by a large margin. Therefore, with careful consideration of the estimates presented for the multiple locations holding the species in Leader et al. (2016), the population is placed here in the band of 2,500 – 9,999 mature individuals, which equates to 3,750-14,999 individuals in total, rounded here to 3,500-15,000 individuals.
Trend justification
The species is suspected to be declining at a moderately rapid rate, owing mainly to agricultural intensification and persecution.
This species was historically fairly common over a large area encompassing China, Hong Kong, Chinese Taiwan and northern Vietnam. However, it is undergoing a continuing decline in numbers across its range. The species' stronghold appears to be located in the Dabie Shan mountains of central eastern China (Henan, Hubei and Anhui), where recent surveys counted 400-500 individuals over one week in December 2014 (Leader et al. 2016). In southern China, it is regularly found at only a few sites in Fujian, Jiangxi, Jiangsu, Henan, Guangxi, Sichuan and Guangdong provinces, Hainan island as well as Hong Kong (S. Chan in litt. 2007, P. Leader in litt. 2007, R. Lewthwaite in litt. 2007). In eastern and north-eastern China, the species is rare and localised, occurring in Beijing, Tianjin, Zheijiang, Shaanxi, Hubei, Hebei, Liaoning and Nei Mongol provinces. In most areas where there were hundreds of birds 30 years ago, such as on Kinmen (an offshore island near Fukien, China) where in 1989 up to 176 individuals could be found, the species has declined to such an extent that single figure counts are now the norm (Y. Cheng-te in litt. 2007). In Chinese Taiwan, it is now apparently extirpated, as there have been only three records in recent decades, with the most recent in 1987 (Leader et al. 2016). There were only rare sightings in Vietnam (J. C. Eames in litt. 2007, J. Tordoff in litt. 2007), until the sighting in late 2011 of up to 10 groups, each of c.12 birds, in northern Cao Bang province, northern Vietnam (J. Wright in litt. 2011).
It occurs in open areas with scattered trees, particularly near water and most often close to the coast.
The species is declining as a result of agricultural intensification, particularly the excessive use of pesticides and rodenticides, which has killed most potential invertebrate and vertebrate prey items. Direct persecution by humans, including its use for target practice by children, is likely to have exacerbated the decline (M. Lau in litt. 2007). Additionally, the species is increasingly targeted for the pet trade and found on bird markets (S. Chan in litt. 2018).
Conservation Actions Underway
It occurs at a number of IBAs. The roost at Deep Bay (Hong Kong) is regularly monitored by WWF staff. In China, the species is considered Near Threatened.
52cm - 55cm. Adult is all dark with diagnostic white collar across nape, hindneck and lower breast. Juvenile is similar but plumage lacks gloss and collar somewhat duller with dark feather tips. Voice Call include a loud repeated kaaarr or kaar-karr as well as various cawing creaking and clicking sounds.
Text account compilers
Butchart, S., Ekstrom, J., Mahood, S., Hermes, C., Martin, R., Taylor, J.
Contributors
Tordoff, J., Chan, S., Leader, P., Eames, J.C., Lewthwaite, R., Cheng-te, Y., Wilson, D., Fellowes, J., Trai, L., Huang, H., Lau, M., Wright, J.
Recommended citation
BirdLife International (2024) Species factsheet: Collared Crow Corvus pectoralis. Downloaded from
https://datazone.birdlife.org/species/factsheet/collared-crow-corvus-pectoralis on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/11/2024.