The authors analyzed data regarding shark bycatch in western & central Pacific longline fisheries from 2013-2021, and the influence of environmental and spatial factors. Results suggest that several environmental factors- including oxygen concentration, sea surface temperature, and chlorophyll-a concentration- impact shark bycatch per unit effort (BPUE) for multiple shark species. Hotstops of bycatch were identified for bigeye thresher shark (Alopias superciliosus), longfin mako (Isurus paucus), silky shark (Carcharhinus falciformis), oceanic whitetip shark (Carcharhinus longimanus), blue shark (Prionace glauca) and shortfin mako (sIsurus oxyrinchus). All species exhibited annual variations in BPUE, and bycatch risk trended eastward toward equatorial waters, likely due to a higher concentration of fishing effort in those areas.