Statistical modelling of by-catch patterns: a preliminary case study using research fisheries in Subarea 48.6

We report a preliminary result of statistical modeling of grenadier bycatch pattern by bottom longline research fisheries in CCAMLR Subarea 48.6, using generalized linear mixed models with zero-inflation. The result contains several issues including the failure of estimation in considerable number of candidate models, overdispersion and insufficient prediction of zero-catch, suggesting that further improvement is required.