Assessing Hawaii's Stream Habitats: Incorporation of an Ecological Classification of Streams for Improved Conservation Opportunities

Since 2010, Michigan State University has partnered with the Hawaii Fish Habitat Partnership to consider threats to Hawaiian streams and the fishes they support.  The 2010 assessment conducted for HFHP resulted in a set of disturbance indices characterizing relative risk of stream habitat degradation from anthropogenic landscape factors, and since that time, we have worked with HFHP to improve the meaning and utility of the assessment.  In support of the 2015 assessment, we developed an ecological classification of Hawaiian stream reaches based on their potential to support native stream organisms which identifies eleven unique types of streams across the five main Hawaiian Islands.  Scores for the 2015 assessment have been tailored to these groupings to more explicitly characterize condition, with disturbances weighted based on specific threats to stream types.  The assessment also includes new landscape disturbance variables unavailable in 2010, and in addition to accounting for threats draining to streams, we have also summarized disturbances specific to downstream main channels of reaches to account for the condition of the migratory pathways of Hawaii’s native amphidromous species.  These changes have resulted in a more ecologically-relevant assessment of Hawaii’s streams and will yield improved opportunities for their conservation and management.