# Analysis and Prospects of an Antarctic Krill Detection Experiment Using Drifting Sonar [PERSON]
## 1 Introduction  
Antarctic krill is the most abundant marine organism around Antarctica: the total biomass of Antarctic krill is about 300-500 million tons per year [1], and it has significant nutritional and economic value [2, 3, 4, 5]. The annual harvest of Antarctic krill is less than 1% of its total, so nations are now focusing on enhancing krill production and usage rates [6, 4], striving to exploit this resource sustainably without harming the ecological balance or depleting krill stocks. To fully leverage Antarctic krill resources, it is essential to extend beyond merely boosting catch volumes; this entails conducting comprehensive research to understand krill population dynamics and total resources alongside implementing robust resource management and monitoring strategies [7, 8, 9]. These should include setting reasonable catch limits and seasonal fishing moratoriums to ensure the krill's sustainable and healthy development [10, 11]. As the krill industry has evolved over decades, with current global catches totaling around 400,000 tons annually [6], collaborative international research and sustainable management practices are crucial for preserving the krill ecosystem and promoting its sustainable use despite the high costs associated with Antarctic research [5, 11].  
Currently, the assessment of Antarctic krill resources primarily utilizes survey vessels, which predict krill biomass using sonar equipment or fishing data onboard [12, 13]. Many scholars have predicted the biomass of Antarctic krill using acoustic or fishing data with considerable success. However, surveys conducted by vessels are labor-intensive andcostly, and given that krill are distributed in the remote and harsh maritime regions of Antarctica, prolonged survey operations become even more challenging [4]. Sonar, as a common method for marine detection, has been widely applied in recent years. PAM (Passive Acoustic Monitoring) is used to detect marine mammals [14; 15], enhancing our understanding and protection of marine cetaceans. Active sonar technology is often used in resource assessment [12; 13; 16; 17; 18; 19] and marine mapping [20], playing a significant role in these areas. At the same time, sonar technology has been increasingly refined and integrated with emerging technologies like artificial intelligence, allowing it to better serve current production and research work. Buoys, as monitoring and navigational tools at sea, offer the advantages of low cost and flexible deployment [21; 22], and they are currently widely used in fields such as marine research [23; 24; 25; 26], navigational safety [27; 28; 29], meteorological monitoring [30; 31; 32; 33], and fishery [34; 35; 36].  
Therefore, our team proposes the use of small sonar buoys for the assessment of Antarctic krill resources and has conducted preliminary experiments. Utilizing this method for the assessment of Antarctic krill resources is cost-effective, and detection is sustainable. It can serve as an excellent supplement to research vessels for assessing krill resources, reducing the workload of survey vessels. Additionally, since sonar buoys can perform acoustic monitoring over extended periods in designated maritime areas, they help enhance the accuracy of krill resource assessments. This approach offers new insights for the conservation and evaluation of Antarctic krill resources. The preliminary experiments on krill detection have achieved the expected objectives, providing evidence of using drifting sonar buoys to detect Antarctic krill while also identifying some deficiencies. The experimental results and analysis will be detailed in this paper.