This discussion was first published as part of the 2013 Red List update, but remains open for comment to enable reassessment in 2015.
Seychelles White-eye Zosterops modestus is endemic to the Seychelles. It is listed as Endangered under criterion D of the IUCN Red List because it has an extremely small population.
This species was thought to survive only in three tiny areas on Mahé, Seychelles, and appeared to be declining inexorably towards extinction. In 1996, only 25-35 individuals were known (Rocamora 1997). In 1997, a previously unknown population was discovered on Conception (Rocamora 1997). In 1997, this island was estimated to hold “at least 250” individuals (Rocamora and Francois 1999), with c.50 more on Mahé (G. Rocamora in litt. 1999). The population on Conception was estimated at c.275 (244-336) individuals in 1999 and at c.230 (189-266) in 2006, and may be fluctuating or slightly decreasing (R. Bristol in litt. 2004, G. Rocamora in litt. 2007). The population on Mahé was estimated at c.50 birds in 1997 (G. Rocamora in litt. 2007) and at c.60 birds in 2006, and appears to have slightly increased (G. Rocamora in litt. 2007). The transfer of 37 individuals from Conception to Frégate Island in 2001 and 2003 have resulted in the establishment of an estimated population of c.100 individuals there in 2007 (G. Rocamora in litt. 2007), and an estimated global total of c.400 individuals in 2007. Further translocations took place in 2007, when 25 birds were transferred to North Island, and 23 to Cousine (Rocamora and Henriette-Payet 2009). Habitat quantity and quality are both increasing (due to rat eradications and restoration programmes in the islands where the species has been transferred) (G. Rocamora in litt. 2007). Results from a monitoring programme started in 1996 indicate a moderate increase in the total population (G. Rocamora in litt. 2007), which was estimated at c.400 birds in 2007 (Rocamora and Henriette-Payet 2009). If there is sufficient evidence to suggest that there have been more than 250 mature individuals following the translocation in 2007 (for at least 5 years), and that the population is not declining, this species would be eligible for downlisting to Vulnerable under criterion D1+2 of the IUCN Red List (<1,000 mature individuals).
Further information is requested on the population size and trends of this species and comments on its proposed downlisting are welcome.
Rocamora, G. (1997) Red Data Bird: Seychelles Grey White-eye. World Birdwatch 19: 20-21.
Rocamora, G. and Francois, J. (1999) Seychelles Grey White-Eye conservation programme. Birdwatch – Bird News and Nature Notes from Seychelles 29: 20-22.
Rocamora, G. and Henriette-Payet, E. (2009) Conservation introductions of the Seychelles white-eye on predator-free rehabilitated islands of the Seychelles archipelago, Indian Ocean. In: Pritpal S. Soorae (ed.). Global re-introduction perspectives: Re-introduction case-studies from around the globe. IUCN, Gland (Switzerland).