We censused wild buffalo Bubalus arnee in Koshi Tappu Wildlife Reserve, Nepal, in March 2004 using methods employed in earlier surveys, and estimated a population of 159 animals. Since the last census in 2000 the management situation has deteriorated. Guard posts have been evacuated due to the Maoist insurgency. The entire Army Battalion usually posted in the Reserve was at Headquarters at the time of this study and therefore there were no patrols over most of the Reserve, and much human encroachment. Mortality from flooding and road deaths, and possibly poaching for meat, were evident, and males suffered more mortality overall than females. Despite these threats the population had increased since 2000, albeit at a lower rate than previously. Active management, including interventions within the Reserve and a translocation of some individuals to Chitwan National Park, are recommended.