Invasive alien plant species and their effects on the habitat utilization of wild ungulates in parsa national park, Nepal

Abstract

Invasive alien plant species (IAPS) often have a negative effect on native biodiversity including wildlife, but such effects are specific to habitat and species. This study recorded the occurrence of IAPS in Parsa National Park (PNP) of Nepal and assessed their impacts on the habitat utilization of wild ungulates. Data was collected from December 2022 to October 2023. A total of 106 plots of 50*50 m 2 at the interval of 1 km were established in PNP. The occurrence of invasive species was recorded through visual observation and wild ungulates were recorded using camera traps and sign survey. A total of eight IAPS were recorded in the survey plots. Among them, siam weed (Chromolaena odorata) had the highest coverage i.e. 44%, followed by billy goat (Ageratum conyzoides) 21% and the lowest coverage of goat weed (Ageratum houstonianum) (1.06%) and sicklepod senna (Senna tora) 1.06%. The IAPS coverage was influenced by tree canopy cover, and proximal to road and settlement. A total of 20 IAPS (8 from survey plots and 12 from opportunistic survey) were sighted along the route from PNP. Among the six wild ungulates, the highest detection was of wild boar in 60 plots, followed by chital, barking deer, sambar, and nilgai, and the lowest detection was of gaur in 23 plots. The occurrence of barking deer, and sambar was influenced by IAPS coverage. This study suggests the management of IAPS in PNP for the survival of wild ungulates.