With regard to non-Pacific halibut species catch data (option 6 above), these include a mixture of subsample counts (20% observations) and whole-haul counts (100% observations). It should also be noted that amounts of fishing gear used can vary by region and year. Data need to be standardized prior to use.
In addition, IPHC staff has developed several adjustment factors to the survey CPUE indices to correct for possible regional differences in catchability. One of the potential differences is competition for hooks resulting from different suites and densities of competitors. These correction factors are available below. For background on the hook competition adjustment factor, please review p. 33 of IPHC-2021-SRB019-05 IPHC Fishery-Independent Setline Survey (FISS) and commercial data modelling.