Relevance of Odonata guild dynamics in the Upper Klang basin, Malaysia in 1963–64 to the conservation of fragmented river basins

Malaysian rainforests have become highly disturbed and converted for export-oriented agriculture and urban-industrial infrastructure. Odonata guilds were studied at two breeding sites in pristine and disturbed forested upland Saraca streams of the upper Klang River basin, Malaysia in November 1964 to December 1964. Their lessons could offer clues for biodiversity conservation in fragmented river basins. Adult Odonata species were found to depend on scarce and changing spatio-temporal habitats, and oviposition resources in fragmented riparian biotopes, occurring mostly in pool biotopes. Their species distribution exhibited a log-series pattern, with most species being rare while few were abundant (dominant). Higher species density occurred in disturbed than in pristine biotopes. Adult Odonata species phenology varied over short temporal scales – weekly and monthly, if not daily – with changes in habitat and oviposition resource availability in biotopes affected by unpredictable rainfall, and flows or spates influencing spatio-temporal land-water interactions. Adult aggregation and breeding occurred mainly during rainless days during the ending of the Northeast Monsoon, when water levels recede and become somewhat stable. Eurytopic non-riverine species with high biotic potential dominated disturbed forested streams and ‘masked’, but not displaced, the phenology of rarer riverine species. These findings highlighted the need to explore alternatives for conserving Odonata species guilds and biodiversity in fractal patches, fragmented landscapes, and ecosystems affected by ecohydrological and ecotonal functions, to generate specific ecosystem goods and services for sustainable use through biogeographic approaches in co-management in river basins.