Recovery of Avian Diversity in An Abandoned Human Settlement in Western Forests of Thailand

Abstract

Avian diversity and recovery in abandoned human settlements (AHS) and dry evergreen forests (DEF) were monitored continually from 2000 to 2003, in Thung Yai Naresuan Wildlife Sanctuary, western Thailand. The monitoring objective was based on the Shannon-Wierner index (H′) of bird
species after abandonment of the settlement areas. The line transects ran for 900 m in the AHS and continued for another 900 m in DEF, allowing for 100 meters for the edge effects. The study recorded 255 bird species. The H′ indices in the AHS were lower than those in the DEF sites and were significantly lower (P<0.05) during the cool season and the summer season of 2002. Comparisons of the H′ index in different aged (6–12 years old) sites indicated that the H′ indices in the AHS from 6 to 10 year-old sites tended to be lower than the those in DEF sites. However, the H′ index was greater in the 12-year old AHS than in the DEF during every rainy season, the cool season of 2002, and the summer season of 2003. The study suggested that bird diversity in protected areas showed a clear recovery pattern after abandonment of human resettlement. It is recommended to limit human disturbances as much as possible to allow for maximum avian diversity to recover.