CCAMLR

This is a preliminary report on acoustic survey conducted by the Japanese fishing vessel in the 2011/12 fishing season.  Based on the CCAMLR EMM11/35, F/V FUKUEI-MARU collected acoustic data as a pilot study to monitor Antarctic krill distribution and fishing grounds formation.

The coordinated collection of acoustic data from the krill fishing fleet will potentially lead to large amounts of stored raw data of variable quality, which need to be scrutinised and processed in order to provide useful information. Different software packages are available to accomodate this. This document provides some background for evaluating the capacity of the software suite Large Scale Software System (LSSS), which is designed for handling large amounts of acoustic data. Through example data from the krill fishing vessel ’Juvel’ it is here demonstrated that LSSS has flexible and efficient data loading, pre-processing and database functionality. The well-documented Simrad standard ’.raw’ data format is used as LSSS native format, while other formats have to be converted.

Omnidirectional sonars (herein sonars) are capable of providing an alternative view of Antarctic krill distribution, and potentially abundance. Data from sonars can be used independently of conventional downward-looking echosounders or as an additional information source as a compliment to existing acoustic surveys. Sonars are capable of sampling large volumes of water and can image entire krill swarms and track changes in swarms through time.  Some commercial krill fishing vessels, e.g.  ‘Juvel’ and ‘Saga Sea', routinely use sonars, and we provide example data and swarm descriptions from these vessels.  The purpose of this paper is to stimulate discussion on the utility of sonars to describe krill within a survey area and to consider the metrics (descriptors) we outline in the paper.  We hope the outcome of our discussions will facilitate the use of sonar data collected from a variety of vessels and sonar types by providing guidance on the operation, sonar system settings, and data analysis techniques.