NT
Comoro Blue-pigeon Alectroenas sganzini



Justification

Justification of Red List Category
This species has a small range and may face threats from habitat clearance and degradation, and hunting. Although it appears to persist in some degraded forest, further information regarding the area of impact of hunting and population trends may mean it qualifies as Vulnerable. Therefore, it is considered to approach the threshold for Vulnerable and hence is listed as Near Threatened.

Population justification
The global population size has not been quantified, but the species is reported to be extinct in some localities, common in others and extinct on several small islands (del Hoyo et al. 1997). The population on Mayotte has been estimated at 9,800 individuals (Rocamora 2004).

Trend justification
There appears to be no evidence of a decline in the species between 1985 and 1989 on the Comoros (Stevens et al. 1992). However, hunting does continue to be a threat to the species and so the population is tentatively suspected to be in decline owing to unsustainable levels of exploitation.

Distribution and population

This species is found in the Comoros, Mayotte (to France) and Aldabra (Seychelles). It has potentially gone extinct on some small islands (see Safford 2013). Tracewski et al. (2016) estimated the maximum Area of Occupancy (calculated as the remaining tree area within the species’s range) to be c.1,085 km2, rounded here to 1,100 km2. However, it can persist in areas of degraded forest (Safford 2013), and so this may be an underestimate.

Ecology

This species is predominantly found in forest, but can also occur in degraded and logged forest (e.g. banana tree understorey) (see Safford 2013). It is found throughout Aldabra, but in the Comoros and on Mayotte it is predominantly montane (up to 1,800 m on Grand Comore), with limited records down to sea level (see Safford 2013).

Threats

Its habitat is diminishing as a result of charcoal production and shifting cultivation (Louette 1988). Hunting is a threat on all four islands (Safford 2001a, 2001b; Stevens and Louette 1999).

Conservation actions

Conservation Actions Underway
Introduction of this species to other islands from Aldabra is being considered (potentially onto Assumption and Cosmoledo) (see Safford 2013).


Conservation Actions Proposed
Conduct surveys to better understand the species's population size and trends. Also conduct research to fully investigate the species's tolerance of habitat degradation. Assess the impact of hunting on the species, and if necessary attempt to control/limit hunting of this species, potentially using education and outreach programmes. Protect habitat from clearance and degradation

Acknowledgements

Text account compilers
Butchart, S., Ekstrom, J., Westrip, J., Symes, A.


Recommended citation
BirdLife International (2021) Species factsheet: Alectroenas sganzini. Downloaded from http://www.birdlife.org on 21/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/10/2021.