Over the past 60 years, thisspecies has experienced an ongoing decline in populationsize. In 1990 the population was estimated to consistof 20 million individuals (Wingard and Zahler, 2006),falling to fi ve million by the most recent assessment in2001, indicating a 75% decline (Batbold, 2002). It is estimated that more than 1.2 millionskins per year have been traded since the late 1800s, with as many as three million individualsremoved from the population in 2004 (Wingard and Zahler, 2006). Generation length has beenestimated as six years based on data from Nowak (1991). This species qualifi es as Endangeredunder Criterion A2ad, based on observed declines of greater than 50% over the past threegenerations primarily due to exploitation and disease. The assessment remains unchangedfollowing application of regional criteria as there is no signifi cant immigration from adjacentcountries.