Monitoring of Avifauna to Estimate the Effect of Ecological Restoration in Mukojima, Bonin Islands

Abstract

Mukojima (Muko Island) of the Bonin Islands, Japan, has undergone multiple ecological changes as part of ecological restoration projects, such as the eradication of invasive species. However, the effect of these projects on the resident terrestrial birds of Mukojima are unknown. In this study, we performed censuses in two transects to record quantitative data of resident terrestrial bird species of Mukojima. In addition, all bird species observed from February to May 2008–2012 were also recorded. Only two species, the Blue Rock Thrush Monticola solitarius and the introduced Japanese White-eye Zosterops japonicus were regularly observed. There were no changes in abundance of either species between 2007 and the present study, except for an increase in the Blue Rock Thrush along one transect. We observed a total of 74 bird species, 32 of them newly recorded on Mukojima. Although preliminary, our results contribute to an understanding of the effects of ecological restoration on the avifauna of Mukojima.