Current distribution and abundance of slender lorises (Loris tardigradus and L. Iydekkerianus) in Sri Lanka

Abstract

Two species of slender lorises are currently recognized in Sri Lanka. They are Sri Lanka red slenderloris (Loris tardigradusj and Grey slender loris (L. lydekkerianus i, with four currently recognizedsub-species; viz. Western red slender loris (L. t. tardigradus), Montane slender loris (L. t.nycticeboidesi, Northern grey slender loris (L. 1.nordicusi, and Highland slender loris (L. 1.grandis).The objective of this survey was to map the distribution and estimate the abundance of lorises in SriLanka. The study was initiated in 2002 and continues to date. Thus far forty-five sites across all ofthe ecological zones have been surveyed covering approximately 400 krn-. In six of these sites, loriseswere not recorded. Of the other 39 sites, 223 sightings of slender loris (L. t. tardigradus (n = 86), L.t. nycticeboides (n = 3), L. 1. nordicus (n = 122), and L. l. grandis (n = 12). Abundance estimates, 'base on sightings of animals krn', were: L. t. tardigradus (0.5-8), L. t. nycticeboides (0.03), L. I.nordicus (0.7-13). and L. 1. grandis (0.3-4) were recorded. The abundance of lorises varied indifferent habitat types with the highest abundance oflorises occurring in the dry zone monsoon forests.The least abundance of lorises was recorded in the cloud forest.