Notes on the availability of three important finfish species in offshore waters of the lower South Shetland Islands (Subarea 48.1)

In 1998, an offshore scientific trawl survey of bottom fish sampling within the 50-500 m isobath of the lower South Shetlands Islands (King George Island to Low Island) was conducted. In addition, the abundance of two commercially important Antarctic fish, Notothenia rossii and Gobionotothen gibberifrons has been monitored relative to another potentially exploitable fish, Notothenia coriiceps, in the lower South Shetlands Islands from inshore sites mainly at Potter Cove from 1983 to 1999. These studies have been conducted using trammel nets sampling bottom depths from 5 to 50 m. Information from this trawl survey was compared to the 1998 Potter Cove data to examine potential inshore-offshore relationships for these three species. In general, these two data sets are complementary, and demonstrate well-defined changes in size that take place between inshore and offshore sampling. By combining samples collected from a single year, the sample size and regression range available for length-weight relationships can be increased. However, the value of these data as a combined singular data set for one year of sampling is limited. A future offshore survey coupled with inshore sampling would provide substantially more information, and allow a more direct comparison of the two data sets to be realised, particularly with respect to trends between the three species.