The influence of an invasive tree species (Myrica faya) on the abundance of an alien insect (Sophonia rufofascia) in Hawaiʹi Volcanoes National Park Original Research Article

Following its accidental introduction into Hawaiʹi in 1987, Sophonia rufofascia Kuoh and Kuoh (Homoptera: Cicadellidae) has become a concern due to the wide range of plant damage that can result from its feeding and ovipositing. Sophonia rufofascia abundance was monitored on the invasive non-native Myrica faya Aiton tree, the dominant native Hawaiian tree Metrosideros polymorpha Gaudich-Beaupre, and on two common native shrubs in paired areas within Hawaiʹi Volcanoes National Park. These areas included Special Ecological Areas (SEAs) — where Myrica faya had been mechanically removed, and in immediately adjacent control areas — where Myrica faya was still present. Sophonia rufofascia abundance was five times greater on Myrica faya than on co-occurring Metrosideros polymorpha in control areas. In addition, the abundance of S. rufofascia on native plants was between two and 19 times greater in areas where Myrica faya was present, than in those areas where the tree had been mechanically removed. These results indicate that Myrica faya promotes a localized increase in S. rufofascia abundance.