The homogeneity of krill (Euphausia superba) length composition in commercial trawl catches (hauls) was investigated by comparing length compositions from different parts of the same haul. There was no significant difference (P>0.5) in 53 out of 60 hauls. Therefore it is concluded that sampling from one part of the haul provides a reasonable estimate of length composition in the entire haul. In contrast to small variations in length composition within the same haul, variation between different hauls was most noticeable in areas where krill length frequency compositions were bimodal.