Browsing by Subject "longline CPUE index"

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    Exploration of empirical management procedures based on longline CPUE index and aerial survey index
    (2010) Kurota, Hiroyuki; Fujioka, Ko; Sakai, Osamu; Butterworth, Doug S
    We evaluated performance of four Management Procedures (MPs) with empirical algorithms to determine TACs using information from the longline CPUE series and the aerial survey index. This MP exercise shows that TAC levels in the future are quite different depending on six management targets (tuning levels for spawning biomass recovery) that were proposed by the commissioners in April 2010. It also indicates that MPs with larger TAC reduction in the early years, which might not be preferred from a socio-economic viewpoint, enable quicker stock rebuilding and greater TAC increases in later years, even though they achieve the same long-term management target for spawning biomass recovery.
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    Open Access
    Further evaluation of empirical management procedures based on longline CPUE index and aerial survey index
    (2010) Kurota, Hiroyuki; Fujioka, Ko; Sakai, Osamu; Takahashi, Norio; Butterworth, Doug S
    Based on recommendations made during the third Operating Model and Management Procedure Technical Meeting (June 2010, Seattle), we have revised and evaluated “HK” Management Procedures (MPs) using empirical algorithms to determine TACs using information from the longline CPUE series and the aerial survey (AS) index. The exploration of HK variants showed that this MP can behave in a variety of ways as its control parameters and sub-algorithms are changed. As evident also from previous trials, MPs with larger TAC reduction in the early years, which might not be preferred from a socio-economic viewpoint, enable quicker stock rebuilding and greater TAC increases in later years, while still achieving the same long-term management target for spawning biomass recovery (though this comparison is complicated by transient effects).