The Age-structured Production Modelling approach for assessment of the Rock Lobster Resources at the Tristan da Cunha group of islands

The stock assessment approach for all four islands of the Tristan da Cunha group is to use an age-structured production model (ASPM) to fit to catch, longline standardised CPUE and catch-at-length (CAL) data. The models consider only catches from 1990, i.e. models are initiated in 1990. The method for setting up the initial population age structure in 1990 is given below. Note that these assessments do not take into account any effect of the OLIVA oil/soya spill even which took place in March 2011, as the data for these assessments were collected prior to this event.