The International Pacific Halibut Commission adopted a coastwide stock assessment methodology at its 2008 Annual Meeting. This methodology accommodates movement of halibut at all ages and determines a single coastwide estimate of exploitable biomass. This single coastwide estimate is then apportioned into IPHC regulatory area estimates using data from the fishery-independent IPHC setline stock assessment survey and estimates of bottom area from each regulatory area. This apportionment resulted in a different distribution of the exploitable biomass than had been estimated with the previous closed-area stock assessments.


At the 2008 Annual Meeting, the IPHC Commissioners and industry endorsed the coastwide stock assessment methodology but wished to have further investigation of methods for apportioning the coastwide exploitable biomass estimate into IPHC regulatory area estimates of biomass and catch limits. In addition, the Commission requested that the staff update industry on the most recent results and understanding of halibut movements arising from Commission tagging programs, particularly the PIT-tag experiment. This workshop addressed both of these issues.

Questions on the workshop can be directed to either Laura Black or the IPHC office at (206) 634-1838.

Using IPHC Widgets

Widgets are a type of graphical user interface (GUI) that can be used to display information changeable by the user, such as a window or a text box. One of the advantages of a widget is to provide a single interactive tool to manipulate data, specify data inputs, model characteristics and view results. The International Pacific Halibut Commission developed two widgets for the 2008 IPHC Biomass Apportionment Workshop, one to illustrate alternative apportionments and another one to illustrate the effects of migration and fishing on the distribution of biomass. An updgraded version of the migration/fishing widget was used at the Biomass Apportionment Workshop II.


Documents relevant to the Biomass Apportionment Workshop