Cooperative Fish and Wildlife Research Units Program: Hawaii
Education, Research and Technical Assistance for Managing Our Natural Resources

Freshwater is a critical driver for island ecosystems. Climate change has fundamentally altered the water cycle in these tropical islands. The changes in dynamic patterns of streamflow could result in the temporal and spatial difference in the fluvial, estuarine, and coastal habitats. In particular, these habitats support the nine native aquatic species in Hawaii at different stages of their amphidromous life cycle. To examine how changes in streamflow regime has impacted habitat quality for native migratory aquatic species, an ongoing project has examined statewide long-term stream records. We are in the process of building hydrological models and connecting the stream dynamics with existing biological data to address the climate impact on stream habitats. In this study we will examine the historical daily flow and rainfall records to describe the hydrological patterns of stream habitats in Hawaii and we will empirically evaluate the swimming performance of various non-native species in order to better predict the effect of extreme high flow events on non-native fish populations in various stream reaches. With similar concept, we will connect with like-minded researchers in Puerto Rico to explore and develop a comparative study to address the changing aquatic ecosystems due to the extreme flood. This research project has arisen explicitly from existing research and discussions with local stakeholders (e.g., Commission on Water Resource Management, Hawaii Fish Habitat Partnership, National Fish Habitat Partnership, Pacific Island Fisheries and Wildlife Services) and researchers from different regions. Intermediate results will be presented to stakeholders to determine the most useful format for final dissemination to user groups.