The diademed sifaka makes a warning call resembling the sound "kiss-sneeze" when a terrestrial predator is perceived; the sole terrestrial predators of P. diadema are the fossa and Nile crocodile. Sexual maturity occurs after age two or three, with the male maturing somewhat more slowly than the female. Little is known of mating behaviour; however, it is believed that the female is receptive to mating only a few days per year. Being dominant, the female has the greatest input to mate selection. Copulation occurs in the summer (around December), and the expected number of births is one offspring per female per annum. Conservation issues The diademed sifaka is classified as critically endangered on the IUCN Red List, and is listed in CITES Appendix I. As of the year 2002, population estimates for the species range between 6,000 and 10,000 individuals. The primary threat is habitat reduction due to shifting cultivation by native peoples. This threat is also present even within designated national parks, which are sufficiently distant from the center of government, that enforcement of existing national laws protecting P. diadema habitat is problematic. Pressures of population growth in central and eastern Madagascar are causing many of the rural poor to seek subsistence by seizing whatever forest lands are available and undertaking slash-and-burn tactics as their initial step in a shifting cultivation system. Returns from such land use are usually meager, yielding small amounts of charcoal, firewood or grass crop for grazing of zebu. Classification The diademed sifaka and three other sifaka species form a tight species group within the genus Propithecus. The other three species are Milne-Edwards' sifaka (Propithecus edwardsi), Perrier's sifaka (P. perrieri), and the silky sifaka (P. candidus). All of these species have luxuriant silky coats and are powerful leapers. They share similar characteristics of gestation length (four months), age of sexual maturity, female dominance, life expectancy (18 years) and propensity for sunbathing while stretched out on a branch. They differ distinctly in colouration and markings, except for having universally totally black faces. References External links University of Michigan fact sheet for diademed sifaka Primate Info Net Eastern Sifakas Factsheet Sifakas Mammals of Madagascar Critically endangered fauna of Africa Mammals described in 1832 Fauna of the Madagascar subhumid forests Madagascar lowland forests Taxa named by Edward Turner Bennett