Justification of Red List Category
This species is classified as Near Threatened because it is declining at a moderately rapid rate, owing to hunting and habitat destruction. If brown tree-snake Boiga irregularis were to be accidentally introduced to other islands in its range, the species may warrant uplisting to Vulnerable.
The global population size has not been quantified, but the species is described as rare on Guam, uncommon in the Mariana islands north of Guam and uncommon on Yap (Gibbs et al. 2001).
Recent surveys apparently suggest the species is declining in line with known threats.
Alopecoenas xanthonurus occurs widely in the Northern Mariana Islands (to USA) and on Yap in the Federated States of Micronesia. It has become extirpated from Guam (to USA) owing to predation by the introduced brown tree snake Boiga irregularis, and although single birds turn up once every few years, these are almost certainly individuals dispersing from the island of Rota, 60 km to the north (G. Wiles in litt. 1999). The highest population is probably on Rota where c.2,400 birds were estimated in 1982 (Engbring et al. 1982), but this population is declining as a result of predation by the invasive tree snake (H. Roberts in litt. 2009). It is fairly common on Saipan where up to 72 birds/km2 were recorded in limestone forest in 1991-1993 (Craig 1996). It is rare on Yap where the population was estimated at c.195 in 1984 (Engbring et al. 1990).
The species inhabits native forest, secondary forest, plantations, introduced tangan-tangan Leucaena leucocephala thickets and habitat mosaics including fields, but appears more frequent in native forest than in disturbed habitats (Engbring et al. 1982, Jenkins 1983, Engbring et al. 1990, Craig 1996). In contrast to other Gallicolumba it is largely arboreal; it feeds in the forest canopy taking fruits, seeds and flowers.
The species can still be legally hunted in the Northern Mariana Islands (G. Wiles in litt. 1999) and must be affected by habitat loss. B. irregularis appears to be established on Saipan and Rota and the greatest threat to the species would come from the accidental introduction of B. irregularis to other islands in its range.
Conservation Actions Underway
A captive breeding conservation program was established by officials of the Commonwealth of the Northern Mariana Islands, United States Fish and Wildlife Service, and a consortium of AZA facilities making up the MAC group (H. Roberts in litt. 2009). Conservation Actions Proposed
Monitor populations, particularly those in the Northern Marianas. Restrict hunting in the Northern Marianas. Set aside and protect areas of habitat which support good numbers of the species. Take measures, e.g. snake barriers around ports, to prevent the introduction of B. irregularis to islands which are currently snake-free. Further develop the captive breeding programme to support future reintroductions and supplementation.
Text account compilers
Derhé, M., Mahood, S., O'Brien, A., Shutes, S. & Stattersfield, A.
Roberts, H. & Wiles, G.
BirdLife International (2019) Species factsheet: Alopecoenas xanthonurus. 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.