Abstract


SEASCAPE MODELS REVEAL THE EFFECTS OF FISHING PRESSURE ON HABITAT USAGE OF CORAL REEF FISHES

The influence of habitat has long been understood to play a primary role in structuring fish assemblages and driving their distributions. Interactions between multiple variables across scales determine habitat suitability and quality for individuals and species. In addition to physical variables such as wave energy, a major factor structuring fish assemblages is the impact of fishing. Biomass of targeted reef fishes under low, medium, and high fishing pressure in the main Hawaiian Islands was modeled based on a suite of remotely sensed habitat variables, including structural and spatial pattern metrics, in a seascape ecology approach. A fishing pressure index based on accessibility to humans and scaled by total fishing effort by island was used to stratify reef fish survey locations. Boosted regression trees revealed that even very low fishing effort (<5 trips/ha) had implications for resource fish biomass. For all target fish combined, structural complexity emerged as the key predictor across all fishing pressure categories. Small-bodied fishery species were associated primarily with structural complexity at low levels of fishing, suggesting the influence of predation, while the distribution of large-bodied species was driven largely by wave power, which may reduce fishing pressure and mitigate land-based pollution. This novel approach reveals how human influence affects the relationship of reef fishes to their environment and has important implications for ecosystem-based management of nearshore fisheries in Hawaii.

Authors

Stamoulis, K. A., Curtin University / University of Hawaii, USA, kostanti@hawaii.edu

Donovan, M. K., University of Hawaii at Manoa, USA, mdono@hawaii.edu

Delevaux, J. S., University of Hawaii at Manoa, USA, jademd@hawaii.edu

Costa, B. M., NOAA Biogeography Branch, USA, bryan.costa@noaa.gov

Lecky, J., University of Hawaii at Manoa, USA, jlecky@hawaii.edu

Pittman, S. J., NOAA Biogeography Branch, USA, simon.pittman@noaa.gov

Poti, M., NOAA Biogeography Branch, USA, matthew.poti@noaa.gov

Williams, I. D., NOAA Coral Reef Ecosystem Program, USA, ivor.williams@noaa.gov

Wedding, L. M., Stanford University, USA, lwedding@stanford.edu

Friedlander, A. M., National Geographic Society, USA, alan.friedlander@hawaii.edu

Details

Oral presentation

Session #:21
Date: 06/23/2016
Time: 15:15
Location: 310 THEATER

Presentation is given by student: Yes