Non-Native Plants Provide Nectar and Host Plant Resources to Native Butterflies

Abstract

Urban restoration projects often aim to completely remove non-native plant species from the restored landscape and replace them with native plant species. However, this is unrealistic as early successional plants in urban settings comprise predominantly of non-native plant species. In this study, we investigate whether native butterfly species showed a preference on using native versus non-native plant species in their nectar sourcing and caterpillar host plant choice in two urban gardens at Monash University Malaysia. Native butterflies significantly preferred non-native plant species as nectar food plants, suggesting butterflies are generalists in nectar sourcing. Native butterflies showed no preference towards non-native plants as caterpillar host plants. However, six native butterfly species in our study (Zizula hylax, Hypolycaena erylus, Chliaria othona, Junonia orithya, Yppthima spp., and Eurema hecabe) can use non-native plants as their caterpillar host plants. This demonstrates the usefulness of these non-native plant species in an urban garden in maintaining native butterfly biodiversity. This study indicates a paradigm shift is required among urban ecologists to recognize that not all non-native plants have negative impacts on biodiversity. For more effective urban restoration planning and management, further research emphasising how native insects use non-native plant species is required to maximise biodiversity and ecosystem services restoration.