VU
Grey Imperial-pigeon Ducula pickeringii



Justification

Justification of Red List Category
This species occupies a very small range, currently occurring at perhaps fewer than ten locations. Its range, habitat and numbers are known or inferred to be in decline owing to the increasing conversion of natural forests to palm plantations. These factors qualify it as Vulnerable.

Population justification
A population estimate of 2,500-9,999 individuals has been derived from analysis of records and surveys in BirdLife International (2001). This equates to 1,667-6,666 mature individuals, rounded here to 1,500-7,000 mature individuals.

Trend justification
The species is suspected to be in decline owing to the on-going loss and degradation of its forest habitat, combined with hunting pressure.

Distribution and population

Ducula pickeringii is known from c.20 small islands off Palawan, Mindanao and in the Sulu archipelago in the southern Philippines, c.13 small islands off the mainland coast of Sabah, Malaysia (north Borneo), the Derawan Islands (including Sangalaki, Kakaban and Maratua), East Kalimantan, Indonesia and the Talaud islands off northern Sulawesi, Indonesia (Collar et al. 1999). Early reports describe it as plentiful at several localities. There are recent (post-1980) records from eight islands in the Philippines (Baguan, Cadiao, Lagen, Tandubatu, Rasa, Bugsok, Pandana and Ursula as well as in Malampaya Sound and Honda Bay), four islands off Sabah, and Sangalaki (Meier 2004) and Karakelang islands (Indonesia), with a maximum count of c.30 on key islands Ursula (Philippines), and Pulau Mantanani (Sabah, Malaysia) indicating that its range and population have decreased significantly. It is reputedly still common on the Talaud Islands (J. Eaton in litt. 2012).

Ecology

It inhabits a variety of lowland, primary forest-types, also frequenting secondary forest and cultivated areas with trees. It has been noted feeding on fruits of Ficus procera and Cananga odorata, both common trees in primary forest and secondary habitats (Riley 2003). Little is known about its movements. It is reportedly resident on some northern Bornean islands, but certainly moves between Philippine islands, and varied in abundance from 1995-1997 on Karakelang, Indonesia. Like other small-island specialists, it presumably wanders in search of food.

Threats

Habitat clearance and degradation are the primary threats, with native forest on small islands being replaced by plantations across much of its range. The species's large size and unwary disposition render it vulnerable to hunting whenever it comes into contact with human populations; birds are taken for food, pets and trade. Introduced mammalian predators may cause birds to abandon some islands. Tourism developments may place pressures on island populations when habitat is cleared and through disturbance (G. Davison in litt. 2007). However, some resort development may be positive where resort grounds provide a safe haven (Q. Phillipps in litt. 2012). The effect of competition with Green Imperial-pigeon D. aenea is not understood but this species has begun to outnumber D. pickeringii on Rasa Island (P. Widmann in litt. 2007).

Conservation actions

Conservation Actions Underway
There are recent records from several protected areas: Baguan Island within the Turtle Islands Marine Natural Park (Philippines), Tunku Abdul Rahman National Park (off Sabah), the Maratuas and Pulau Mantanani Bird Sanctuary (G. Davison in litt. 2007). Rasa Island (southern Palawan) has also been protected under municipal law since 1999 and under national law since 2005. The species may benefit at this site owing to a wardening scheme in place primarily for the conservation of Philippine Cockatoo (P. Widmann in litt. 2007). The Karakelang Hunting Reserve (Talaud islands) may also offer some protection, but requires evaluation to define boundaries and management needs.

Conservation Actions Proposed
Conduct comprehensive surveys of islands, especially in the Sulu archipelago, to clarify its current status, movements and ecological preferences. Assess the potential importance of the extensive mangroves along the east Kalimantan/Sabah coast through further surveys. Propose sites/islands supporting key populations for establishment as strict protected areas, as appropriate (e.g. Ursula). Eradicate macaques and black rats from protected islands. Devise and initiate conservation awareness campaigns to control hunting and curb deforestation on key islands. Seek ban on trade in Imperial pigeons. Review taxonomic status of two subspecies (D. p. pickeringii and D. p. langhornei).

Identification

40 cm. Largish imperial-pigeon. Pinkish-grey head, neck and underparts, pinkest on breast and throat, greyest on hindneck. Pale eye-ring and band at base of dark bill. Greyish-brown back, rump and wings with slight green iridescence. Blackish-green tail. Dark iris, reddish legs. Similar spp. Green Imperial-pigeon D. aenea is larger, greener with rufous undertail-coverts. Voice A regular 'woo, woo, woo' usually lasting seven notes but at times shorter (Melville 1997), however, other observers report a deep 'whrrooh' repeated intermittently (Q. Phillipps in litt. 2012). Hints Most conspicuous when coming to roost at favoured islands.

Acknowledgements

Text account compilers
Benstead, P., Bird, J., Lowen, J., Peet, N., Taylor, J., Tobias, J., Allinson, T

Contributors
Phillipps, Q., Allen, D., Widmann, P., Eaton, J., Davison, G.


Recommended citation
BirdLife International (2019) Species factsheet: Ducula pickeringii. Downloaded from http://www.birdlife.org on 15/12/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 15/12/2019.