Fishes caught along with the Antarctic krill in the vicinity of the South Shetland Islands during the austral summer months of 1994

Observations on abundance of by-catch fishes were made during the austral summer months of 1994 (from January 12 to February 18) on board F/V Niitaka Maru in the north of the South Shetland Islands. Among 99 net hauls examined, a total of 77 specimens of fishes belonging to 13 species were found in 25 trawl catches (Table 1).
Among by-catch fishes, juvenile Lepidonotothen larseni was the most abundant (26 individuals) and most common species (found at 11 hauls). Juvenile and postlarval Chaenocephalus aceratus (13 individuals from 4 hauls) and Chaenodraco wilsoni (10 individuals from 6 hauls) were also secondary abundant. To compare abundance of each fish species, the index of its occurrence in 100kg of kril1 was calculated (Tables 2 and 3).
Fish abundance could have been depended on the density of krill concentration (Figs. 1 and 2). The large incidental catch of fishes occurred in hauls with the low krill catch rates (Hauls. 36 and 47), and fishes are not found or rare within krill swarms of higher density.