Distribution patterns of pelagic fish, larvae and juveniles collected by RM
T trawls during BROKE survey to CCAMLR Division 58.4.1 were investigated. N
early 2000 individuals, weighing 1210 g, were collected from approximately
1.5 million m(3) of the upper 200 m of ocean, supporting the theory that An
tarctic ichthyoplankton has low biomass. The collection consisted mainly of
P. antarcticum larvae and juveniles and E. antartica sub-adults, with a ra
nge of other notothenioid fish and myctophids. Three distinct biogeographic
zones, with characteristic ichthyo- and zooplankton assemblages, were iden
tified. The Oceanic Zone was dominated by myctophids and, in the western re
aches, the paralepidid N. coatsi. The shelf break zone comprised of myctoph
ids, and the juveniles of notothenioid fish. The shelf zone consisted of no
tothenioid juveniles and sub-adults. Characteristic water masses and associ
ated zooplankton assemblages were found throughout these three zones. Analy
sis of fish stomach contents indicated feeding on locally abundant zooplank
ton taxa. There was niche-partitioning of prey taxa and size classes, betwe
en both sympatric species and between different ontogenetic stages. Fish di
stributions corresponded to known patterns, and extended the known geograph
ic range of several species. (C) 2000 Elsevier Science Ltd. All rights rese
rved.