Re ECF Project: 2014-65

Project Title: Hong Kong arthropod biodiversity and forest health assessment

Applicant: Dr Timothy C BONEBRAKE, School of Biological Sciences, The University of Hong Kong

Total Approved Grant: $499,500

Duration: 1/4/2015 to 31/3/2017

Project Status/Remarks: Completed

The diversity of tropical forest insect species is largely understudied globally (~70% of species remain undescribed) and is especially unknown and uncertain in Hong Kong. This study will implement international protocols in arthropod monitoring in one of Hong Kong's oldest and largest forests, Tai Po Kau, to establish baseline biodiversity information and evaluate forest ecosystem health relative to regional and global forest surveys. The results of this study will be vital as Hong Kong formulates its plan to conserve biodiversity in the face of increasing challenges such as habitat loss, fragmentation, invasive species and climate change.

Summary of the Findings/Outcomes:
The project aims to understand the health of Hong Kong’s 70 years old secondary forests by using arthropod diversity as an indicator; and to compare it to its adjacent primary forest site located in Dinghushan (DHS), China. The project team implemented the international monitoring protocol to sample arthropods in Tai Po Kau (TPK, Hong Kong) and Dinghushan (China), and conducted 429 butterfly Pollard-walk transect walks (1,474 individuals were surveyed), 160 termite quadrat samplings, 100 Winkler samplings (>9,500 individuals were collected), 80 McPhail weekly-traps (>18,000 individuals were collected and 120 light night-traps (1,681 moth individuals were collected). Results show that the secondary forest in TPK has high biodiversity value, for example, 53 butterfly species and 113 moth species were recorded. However, compared to DHS, TPK has generally lower abundance and species diversity. The project team suggested that land use history could be a major driver of these differences, since old-growth forest generally has higher biodiversity than secondary forest, although other factors such as landscape configuration and current anthropogenic impact could be important and should not be excluded. The project team concluded that results regarding arthropod assemblages can provide clues about environmental variation and anthropogenic change. Long-term monitoring will be key in assessing large scale global change impacts.