Estimates of length-frequency in the assessment of mackerel icefish Champsocephalus gunnari in Subarea 48.3

This working document provides details of a modification in the method of calculating length distributions used in the assessment of Champsocephalus gunnari from the length distributions of individual hauls. The effect of these changes in method have little impact on the catches that would have been permitted based on the 2011 and 2013 surveys, but has a larger impact on the catch limits derived from the 2015 and 2017 surveys.