Commercial Line Fishing Estimated Average Annual Catch of Reef Fish, 2003-2013 - Hawaii

Nearshore fisheries in the Main Hawaiian Islands encompass a diverse group of fishers using a wide array of gears and targeting many different species. Communities in Hawaii often rely on these fisheries for economic, social, and cultural services. However, the stress from overfishing can cause ecosystem degradation and long-term economic loss. This layer represents the average annual commercial catch of reef fish by line fishing over the years 2003-2013 as reported in commercial catch data collected by the State of Hawaii Department of Aquatic Resources (DAR) Commercial Marine Landings Database (CML). "Line fishing" is a fairly broad category that can include casting, trolling, hand line, short line, and others. These gears were grouped together for consistency with non-commercial catch estimates from McCoy et al. (2018). Commercial catch is reported to DAR in large irregular reporting blocks by gear and by species.

This layer's spatial footprint aligns with the inshore commercial reporting blocks from the shapefile served on the Hawaii Statewide GIS Program website (Fishchart2008.shp) (http://planning.hawaii.gov/gis/download-gis-data/). Data are filtered by DAR before release such that reporting blocks with less than three fishers reporting are excluded in order to protect fisher identities. It is not possible to explicitly distinguish between boat-based and shore-based fishing based on the gear types reported in CML data. The Ocean Tipping Points (OTP) project filtered the data for line fishing and reef fish species only and calculated average annual catch in kilograms by reporting block to match with data from the Marine Recreational Information Program (MRIP). In marine protected areas (MPAs) where boat-based fishing is not allowed, catch was set to zero; and inside de facto MPAs with restricted access, catch was reduced according to expert input and local knowledge. Average annual commercial catch data were converted from polygon to raster and then divided by the number of 100-m raster cells within each reporting block so that units are comparable to non-commercial fishing layers (kg/ha). The result assumes commercial catch is evenly distributed spatially across each reporting block.