Conservation applications of ecological niche modeling: non-native ferns may compete with native ferns for limited suitable habitat in Hawaiian dryland ecosystems

Abstract

AbstractPremiseCompetition from non-native species and habitat loss are common threats to biodiversity and may act synergistically to increase competition for decreasing habitat availability. We develop a workflow using Hawaiian dryland ferns as a model for the interactions between land-use change and non-native competition in determining available habitat for native species.MethodsWe use fine-resolution climatic variables and carefully curated occurrence data from herbaria and community science repositories to estimate the distributions of Hawaiian dryland. We quantify the degree to which non-natives occupy similar regions of niche space and map the remaining available habitat given land-use change in Hawai‘i.ResultsThe estimated niches for the endemic species (Doryopterisspp.) are more narrow than for the indigenousPellaea ternifolia.Doryopteris angelicahas the lowest proportion of non-native occurrences in its estimated suitable area whileD. decorahas the highest. BothD. decoraandD. decipienshave low proportions (¡20%) of inferred suitable area covering native habitat.DiscussionAreas characterized by shared environmental preferences of native and non-native ferns may also decrease due to human development and fallowed agricultural lands. Our study demonstrates the value of a novel ecological niche modeling approach for conservation risk assessment in a rapidly changing and urbanized island ecosystem.