2014/08/01 by S. Ishihara, Shinya Ishihara, Rodel M. Boyles +11 · 1 citation
Environmental Science · #Wildlife Ecology and Conservation #Ecology and biodiversity studies #Fish Ecology and Management Studies
paper · pdf · doi:10.1017/s0030605314000313
Abstract The Critically Endangered tamaraw Bubalus mindorensis is endemic to Mindoro Island, Philippines, and little is known of its ecology. During 2006–2011 we used community-based monitoring to examine the population status and ecology of tamaraw in the species’ core habitat of Mount Iglit–Baco National Park. Each year, for 5 consecutive days at the end of the dry season, trained local volunteers and rangers or project staff were allocated to 18 vantage points in the study area (c. 160 km 2 ). Tamaraw were categorized as adult (> 5 years), juvenile (2–5 years) or calf (< 2 years), and sexed when possible. During the study period the population was 239–314 (mean 271), with no significant fluctuations in age structure (percentage of adults, juveniles and calves: 57.8, 21.0 and 21.3%) or estimated adult female reproductive rates (29.1%). In adults, but not in juveniles, the sex ratio was biased towards females (1 : 1.86, P < 0.01). Bulls were often solitary (32.2% of sightings), whereas the majority of cows (94.7%) formed small groups of 2–12 individuals of different ages, with or without bulls (53.4 and 46.6%, respectively). These results demonstrate that the population remained relatively stable, maintaining a constant age structure and reproductive rate, and that long-term community-based monitoring was effective for quantitative characterization of the tamaraw's social behaviour, which is critical for conservation and management of the species.