Download FAR 2021/72 Estimation of fishing efficiency and catchability of key species on R.V. Kaharoa South Island trawl surveys

Estimates of the fishing efficiency (Q) for 13 species for the R.V. Kaharoa South Island survey trawl gear were made by eliciting expert opinion. Estimates of areal availability taken from generalised additive model (GAM) analyses of the survey data were multiplied to the Q values to estimate overall catchability for seven key species. In five cases (elephant fish, red gurnard, snapper, stargazer, and tarakihi), catchability values were compared with estimates from integrated stock assessments.