ESR prepress abstract  -  DOI: https://doi.org/10.3354/esr00882

Herd demography, sexual segregation and the effects of forest management on Bornean banteng Bos javanicus lowi in Sabah, Malaysian Borneo

Katie L. Journeaux*, Penny C. Gardner, Hong Ye Lim, Jocelyn Goon Ee Wern, BenoƮt Goossens*

*Email: katie.l.journeaux@btinternet.com

ABSTRACT: Between 1973 and 2010, 39.5% of Sabah’s (Malaysian Borneo) natural forest cover was lost to deforestation and conversion to agriculture, thus the remaining population of endangered Bornean banteng Bos javanicus lowi is being driven towards extinction. The Bornean banteng’s herd demography, sexual segregation and the effects of forest management were investigated at 393 camera locations in 6 forest reserves using generalized estimating equations (GEEs) fitted via generalized linear models (GLMs). A total of 43344 camera trap nights and 832 independent banteng events were captured at 93 locations. The identification of 183 bantengs included 22 herds (>1 individual) and 12 solitary bulls, with a herd size range of 2–21. Significantly larger herds were observed in forest with <8 years of post-logging regeneration (PLR), whereas herds were smaller in forest with <3, 4 and 16 years of PLR. Within these forests, herds were significantly larger along logging roads than in open sites and on forest trails. Herds were significantly larger in upland compared to lowland dipterocarp forest, but significantly smaller when closer to the forest border. Bachelor herds being observed as frequently as mixed sex herds, and a significantly higher capture frequency of female herds in the dry season, supported the theory of sexual segregation. Frequency of calf births was highest in March and September, and significantly more calf captures occurred in June and July. This study contributes to a better understanding of banteng ecology and will assist in the effective management to provide suitable habitat for re-population and their longevity.