Preliminary results from the International Synoptic Krill Survey in Area 48, 2019

Preliminary results from the International Synoptic Krill Survey in Area 48, 2019, are presented. Of the six vessels that participated in the survey, this report provides methods and preliminary results from four (vessels from the Association of Responsible Krill harvesting companies (ARK), Norway, Ukraine, and the United Kingdom), covering 8719 n. miles of acoustic transects and occupying 149 sampling stations. Acoustic transects and trawling were carried out as per survey procedures developed in 2018, which were based on the methods and procedures used in the CCAMLR 2000 krill acoustic survey. Backscatter from krill were delineated using the 'swarms' method and integrated to produce distribution maps of krill NASC (nautical area scattering coefficient). A preliminary spatial cluster analysis of krill length distributions was undertaken to assist with calculating the acoustic target strength values needed to convert krill NASC to biomass. Further integration of data from all survey vessels and standardisation of analysis procedures are planned to be done in conjunction with the upcoming SG-ASAM meeting in August 2018.