INDICATOR VALUES AND CHARACTERISTIC SPECIES OF DUNG BEETLES IN TROPICAL FORESTS OF CAT BA NATIONAL PARK, HAI PHONG PROVINCE

Abstract

Dung beetles (Coleoptera: Scarabaeidae) are considered as an indicator group of habitat modifications. However, little is known about the indicative value of dung beetles for changes in tropical island karst ecosystems of Vietnam. We sampled dung beetles along the gradient of forest disturbances from primary forests to old secondary forests (> 15 years since abandonment), young secondary forests (< 10 years since abandonment) and Acacia plantations (< 10 years old) in Cat Ba National Park, Hai Phong Province. Our main aim is to detect dung-beetle species that could be used as potential indicator species of habitat changes. In total, 10 dung-beetle species were identified as potential indicator species of different forest types in Cat Ba National Park based on the indicator value (IndVal) of Dufrêne & Legendre (1997). Four species were identified as true specialists in old secondary forests including Onthophagus phanaeiformis (Boucomont, 1914), Sisyphus neglectus (Gory, 1833), Copris szechouanicus (Balthasar, 1958), and Onthophagus dorsofasciatus (Fairmaire, 1893). Three species, comprising Onthophagus sp1., Synapsis tridens (Sharp, 1881), and Onthophagus trituber (Wiedemann, 1823) could be considered as the indicator species of primary forests. Caccobius unicornis (Fabricius, 1798) and Onthophagus jeannelianus (Paulian, 1945) were indicator species of young secondary forests; Onthophagus luridipennis (Boheman, 1858) was the indicator of Acacia plantations. In the following, we gave an annotated and illustrated checklist of the indicator dung-beetle species that may be broadly useful for habitat monitoring and conservations in Cat Ba National Park.