Additional sensitivity runs for the closure based estimator and re-runs of the catch based estimator following an update of the catch data ...

• Main Authors: Ross-Gillespie, Andrea, Butterworth, Doug
• Format: Report
• Language: unknown
• Published: University of Cape Town 2024
• Subjects: Biological mathematics; Biostatistics; Applied statistics; Bird Island
• Online Access: https://dx.doi.org/10.25375/uct.25701075; https://zivahub.uct.ac.za/articles/report/Additional_sensitivity_runs_for_the_closure_based_estimator_and_re-runs_of_the_catch_based_estimator_following_an_update_of_the_catch_data/25701075

Updated catches prior to 2011 have been made available and show that the catches taken around Bird Island in 2008-2010 were non-trivial relative to catches taken in other years. Hence the sensitivity runs for the closure based estimator previously requested by the Panel, which treated Bird Island as closed in all years, are no longer a good reflection of reality. The Panel has consequently requested alternative sensitivity runs where the 2008-2010 data are excluded from the input data. Additionally, the Panel has requested that the catch based estimator results be recomputed using the updated catch series. Results for these requests are presented in this document. The results for the alternative sensitivity runs are similar to those for the runs carried out previously, and do not change the conclusion made then that catches taken in the vicinity of St Croix in the years this island was supposed to be closed to the fishery do not compromise the broad results from the ICE for St Croix. The updated catch series ...