Ecomorphological relationships and invasion history of non-native terrestrial bird species on O‘ahu, Hawai‘i suggests ecological fitting during community assembly

The widespread introduction of species has created novel communities in many areas of the world. Since introduced species tend to have generalized ecologies and often lack shared evolutionary history with other species in their communities, it would be expected that the relationship between form and function (i.e. ecomorphology) may change in novel communities. We tested this expectation in a subset of the novel bird community on O‘ahu, Hawai‘i. By relating foraging behavior observations to morphology obtained from live birds at four sites across the island, we found many relationships between species’ morphology and foraging ecology that mirrored relationships found in the literature for native dominated bird communities. Both movement and certain foraging behaviors were related to a species’ tarsus to wing ratio. Further, bill morphology was related to gleaning, frugivory, and flycatching behaviors. The commonness of significant ecomorphological relationships suggests that, within O‘a...