Rapid assessment of insect diversity (Ext.), Kalabakan, Sabah

Abstract

The Sungai Tiagau Forest Reserve is a Class 1 Protection Forest Reserve under jurisdiction of Serudong District Forestry Office of Sabah Forestry Department. This reserve is located in south eastern Sabah, covering an area of 7,010 ha. This study was aimed to document the insect fauna of Sg. Tiagau Forest Reserve (Ext.), as well as to investigate the threats affecting insect diversity. Nocturnal insect diversity was assessed through light-trapping from 7:00 p.m. until 9:00 p.m. for three consecutive nights while diurnal insects were documented through sweep nets and forceps. A mean 58 species of nocturnal insects was recorded from a one-square-metre of the light-trapping cloth within three different sites, with an average of 74 individuals. The mean Shannon Index was 3.84 while Simpson Index was 111.26 and Fisher Alpha Index was 178.48. When making a comparison with other forest reserves in Sabah, this reserve shows moderately low in terms of insect diversity but moderate in terms of species richness. Eight Bornean endemic species were recorded during the survey and that will be provide significant information to enhance the conservation of Sg. Tiagau Forest Reserve (Ext.) and serve as a baseline information for future research. From the insects recorded, they can be used to promote nature tourism by highlighting Bornean endemic and interesting species, such as the iconic butterfly, Rajah Brooke Birdwing. There are a few threats and issues that may affect insect diversity, including forest fire, changes in land-use and encroachment. A cooperation between Sabah Forestry Department with relevant agencies could help in addressing the discussed issues. This first-hand information on insects of the reserve can be included in the formulation plan of a sustainable forest management system as stipulated in HCVRN.