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

Understanding the habitat requirements of species throughout their life history provides insight into the environmental drivers that regulate their distribution and abundance. Identifying essential habitats used by larval and juvenile fishes has become a critical component of Ecosystem-Based Fisheries Management (EBFM) especially for commercially important fisheries species. Billfishes (Blue Marlin Makaira nigricans, Striped Marlin Kajikia audax, Shortbilled Spearfish Tetrapturus angustirostris, and Swordfish Xiphias gladius) are popular sportfishing targets in West Hawaiʻi Island. Despite their commercial and recreational value, there is currently no published information on larval distribution and habitat requirements for billfishes in Hawaiian waters rendering it difficult to predict how environmental change will impact billfish recruitment in this region. This research is being conducted in collaboration with researchers from the University of Hawaii and the National Marine Fisheries Service. This project creates a fundamental baseline of information on larval billfish presence and associated habitat characteristics off West Hawaiʻi improving stock assessments related to spawning and recruitment and providing accurate information for future modeling. These results could also be invaluable for exploring the impacts of changing ocean conditions on preferred larval habitat, and predict billfish spawning conditions and resulting availability of billfish spawning habitat off West Hawaiʻi.