18b. Gulf of Alaska Squids

نویسندگان

  • Olav A. Ormseth
  • Sarah Gaichas
چکیده

Changes in assessment methodology: Assessment of squids is challenging due to a lack of reliable data and their unusual life history. In this document we suggest several alternatives for calculating ABC and OFL using the NPFMC’s tier system. Tier 5 requires reliable estimates of biomass and natural mortality rate (M). Under Tier 5, OFL is calculated as M * biomass, while ABC = 0.75 * M * biomass. For squids, we suggest two alternatives for modifying Tier 5 to accommodate the high turnover rate in squid populations. Option 1 uses a modified value of M based on experience with squid fisheries elsewhere in the Pacific and Atlantic Oceans. Option 2 uses a decay function to account for squid mortality throughout the fishing season.

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تاریخ انتشار 2008