26 April 2011.  Dr. Dittus is a member of the IUCN SSC Primate Specialist Group. At the invitation of the Biodiversity Secretariat, Ministry of Environment, Government of Sri Lanka, he participated in a workshop for the revision of the IUCN Red List for all the mammals of Sri Lanka.

There is high variance in the availability of field data for different mammalian taxa concerning their geographic distribution and abundance in Sri Lanka.  Earlier work by Dittus and colleagues (e.g.CAMP 2003), however, had provided sufficient detail about primates to allow assessments at the level of the 12 different subspecies of the 5 species of Sri Lankan primates.  This is important for conservation management considerations because IUCN Red List criteria applied at the level of subspecies would require a revision of earlier government assessments made at the level of the primate species only. It is hoped that the new finer grained focus would raise the level of protection afforded some of these taxa.