The Montane Slender Loris (Loris tardigradus nycticeboides) is an endangered and endemic primate species inhabiting the montane region of Sri Lanka. Recent studies suggested the  L. t. nycticeboides should be elevated to Critically Endangered status. However, information available for the effective conservation of the L. t. nycticeboides is limited. This research was undertaken to clarify the above issues and to gather data on factors influencing the occurrence of L. t. nycticeboides using the technique of occupancy modeling. The results show that the probability of detection (p) and site occupancy (Ψ) of the L. tardigradus varied due to numerous factors such as altitude, canopy connectivity and canopy height.  Most suitable habitats for L. t. nycticeboides occupancy was montane forests situated in 1600-2100m altitude with tall canopy (height >4m) and good canopy connectivity (canopy openings<25%). Focusing on reducing the negative effects of these factors from anthropogenic activities is essential to ensure that L. tardigradus conservation programs are effective.

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