The level of observer coverage in the krill fishery and the scientific sampling undertaken are summarised. During 2012 all 12 of the vessels that participated in the krill fishery carried observers for some or all of their fishing operations. From a total of 860 vessel days of fishing in 2012 observations of krill length measurements were collected on 375 ‘days’ and fish bycatch was measured on 554 ‘days’. Krill length-frequency distributions showed that the greatest variability in size structure occurred in subarea 48.1 during 2012 when fishing occurred both in Bransfield Strait and to the west of the South Shetland Islands. The 4901 fish measurements from 34 taxa indicate the vast majority of fish caught as bycatch are <5cm in length.