Hawaii FEP - Western Pacific Fishery Council

Clearly, any given species that is part of a multi-species complex will respond differently to anOY-determined level of fishing effort (F OY ). Thus, for a species complex that is fished at F OY ,managers still must track individual species’ mortality rates in order to prevent species-specificpopulation declines that would lead to excessive stock depletion. For the coral reef fisheries, themulti-species complex as a whole is used to establish limits and reference points for each area.When possible, available data for a particular species is used to evaluate the status of individualMUS stocks in order to prevent recruitment overfishing. When better data and the appropriatemulti-species stock assessment methodologies become available, all stocks will be evaluatedindependently, without proxy.Establishing Reference Point ValuesStandardized values of catch per unit effort (CPUE) and effort (E) are used to establish limit andreference point values, which act as proxies for relative biomass and fishing mortality,respectively. Limits and reference points are calculated in terms of CPUE MSY and E MSY includedin Table 27.Table 27: CPUE-based Overfishing Limits and Reference Points: Coral Reef SpeciesValue Proxy ExplanationMaxFMT (F MSY ) E MSY 0.91 CPUE MSYF OY 0.75 E MSY suggested default scaling for targetB MSY CPUE MSY operational counterpartB OY 1.3 CPUE MSY simulation results from Mace (1994)MinSST 0.7 CPUE MSY suggested default (1-M)B MSY with M=0.3*B FLAG 0.91 CPUE MSY suggested default (1-M)B OY with M=0.3*When reliable estimates of E MSY and CPUE MSY are not available, they are estimated from theavailable time series of catch and effort values, standardized for all identifiable biases using thebest available analytical tools. CPUE MSY is calculated as one-half a multi-year moving averagereference CPUE (CPUE REF ). This value has not been finalized yet; however, preliminary valuesfrom the types of commercial fishery data (not including aquarium or aquaculture fisheries)presently available for Hawaii are shown in Figures 23-25. These are time series of data from theState of Hawaii commercial catch reports, screened to include only CHCRT from all gear typesfor the entire area of the MHI. CPUE is estimated as the aggregate weight reported for that year,divided by the number of records for that year. A twenty-year time window is used for the multiyearaverage. Figure 23 presents all CHCRT in aggregate. Figure 24 is for menpachi (Myripristisspp.) while Figure 25 is for weke (Mulloidichthys spp.). These two latter examples were chosenbecause they are well-represented in the catch report database. CPUE REF and E MSY could beestimated directly from this, as shown in the figures. Alternatively, following Restrepo et al.(1998), they could be estimated as E MSY = E AVE , where E AVE represents the long-term averageeffort prior to declines in CPUE. When multiple estimates are available, the more precautionary168