EN
Raiatea Fruit-dove Ptilinopus chrysogaster



Justification

Justification of Red List Category
This recently-split species has a very small range within which it occurs on just five small islands. It is thought to be threatened by predation by the Swamp Harrier Circus approximans and the quality of its habitat is likely to be declining due to invasive plants. For these reasons it is listed as Endangered.

Population justification
On Huahine (75 km2) and Raiatea (168 km2) it was described as reasonably common and occurring at densities of 6-7 per hectare in some parts of Raiatea. On Tahaa (90 km2), Bora Bora (29 km2) and Maupiti (11 km2) it is uncommon, with populations in 1973 estimated at 500, 50 and 100 birds respectively (Gibbs et al. 2001). Current population sizes on these islands are unknown, and there appear to be no estimates for Huahine and Raiatea. The total population is presumed to be greater than 1,000 mature individuals, and may lie within the band 1,000-2,499 mature individuals.

Trend justification
The population is suspected to be declining based on a lack of recent sightings on Maupiti and the presence across the species's range of swamp harrier (Circus approximans), which has been recorded preying on the species (C. Blanvillain in litt. 2018). Additionally, the species's habitat quality is thought to be declining due to invasive plant species (C. Blanvillain in litt. 2018).

Distribution and population

Ptilinopus chrysogaster breeds on Huahine, Raiatea, Tahaa, Bora Bora and Maupiti in the Leeward Islands (French Polynesia). On Huahine (75 km2) and Raiatea (168 km2) it was described as reasonably common and occurring at densities of 6-7 per hectare in some parts of Raiatea. On Tahaa (90 km2), Bora Bora (29 km2) and Maupiti (11 km2) it is uncommon, with populations in 1973 estimated at 500, 50 and 100 birds respectively (Gibbs et al. 2001). Current population sizes on these islands are unknown, although the local people on Maupiti have been reported not to notice the species recently (C. Blanvillain in litt. 2018), and there appear to be no estimates for Huahine and Raiatea. The total population is presumed to be greater than 1,000 mature individuals, and may lie within the band 1,000-2,499 mature individuals. The species's forest habitat is thought to be degraded due to invasive plants and the species is threatened by predation from the introduced swamp harrier (Circus approximans) (C. Blanvillain in litt. 2018).

Ecology

It is poorly-known but occurs in lowland forest to an elevation of 450 m on Raiatea (Gibbs et al. 2001).

Threats

The introduced Swamp Harrier (Circus approximans) may have had an adverse effect on the species in the past and is thought to be the most significant threat currently affecting the species (del Hoyo et al. 1997, Gibbs et al. 2001, C. Blanvillain in litt. 2018). There may be limited hunting for food in parts of the range. Invasive plants are impacting on the quality of the species's forest habitat (C. Blanvillain in litt. 2018). Polynesian rats (Rattus exulans), black rats (Rattus rattus) and cats have also likely played a role in the species's decline (S.O.P Manu 2015).

Conservation actions

Conservation and research actions underway
No targeted actions are known.

Conservation and research actions proposed
Survey all range islands to obtain an up-to-date population estimate. Evaluate current and potential threats. Research the impacts of Circus approximans, invasive mammals and invasive plants. Control invasive plant species.

Acknowledgements

Text account compilers
Symes, A., Taylor, J., Wheatley, H., Ekstrom, J., Butchart, S.

Contributors
Blanvillain, C.


Recommended citation
BirdLife International (2022) Species factsheet: Ptilinopus chrysogaster. Downloaded from http://www.birdlife.org on 16/08/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/08/2022.