To evaluate effects of eradication of invasive mammals on mass and flow of nutrient elements in an island ecosystem, we tested whether aboveground biomass of herbaceous vegetation after eradication of feral goats and nutrient elements in soil would be related to biotic and abiotic environmental factors (seabird nesting, extent of vegetation degradation before goat eradication, species composition of current vegetation and topology) on Nakoudojima Island, a subtropical oceanic island in northern Pacific. Aboveground biomass was correlated only with extent of vegetation degradation before goat eradication. Amounts of carbon and nitrogen in soil were correlated with presence of seabird nesting, extent of vegetation degradation before goat eradication and difference in dominant species in current vegetation. Amount of phosphorus in soil was correlated with seabird nesting, extent of vegetation degradation before goat eradication and topology. Our results demonstrated that distributions of aboveground biomass of herbaceous vegetation and amounts of nutrients in soils after eradication of feral goats are spatially heterogeneous within the island, and that the spatial heterogeneities are related to biotic and abiotic environments.